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1. ATTEN INSTRUMENTS AT3200 ANTENNA EXPERIMENT SYSTEM Manual For Experiment SHENZHEN ATTEN ELECTRONICS CO LTD TABLE OF CONTENTS VARRANT T AND ESPERE Dess PRU RT esteso eer cuta ost a nM uten ceu 2 ETENDE DS UE Ps RT oases E E dasveusbadsvadssaariaeteedsvadsnes 2 PEER E ER OUE T s Sache anaaaecean es ateaneaaacee uate aneaaacnau oanteaneaacnau ate awaaenau eattcawaaeenau ea eueacee es 3 bo GENERAL TONES MATUSO Ness echa his esca itae ia en ies hese at an na eset taut iua ta M aub Ue 3 e hos tern err er reer errr errr cre errr MEME errr cre ME end 3 Orie WP Je p 4 Be ME iic s M dp E pe P 4 CAPE Roe VNSTAUEURTION A ENEGUTIEON COE PROGRAM escena a treten ta ttd tt tein ni 7 PUN ETAF EANAN SOT IE ROGOR AM eh tale ce ae te ace a ae lacie Se ace a E S eae eee as 7 NES S WAI ON etenee a T 8 CHAPTER 2 AOI Ge S TU EOM E EE ME TS cereus be ERR SES ERES RBS sa ca saceuceasasanece vase neeasaoesecaseseuecacesenese ceacsuasee 10 EAPERLMEND Sec RAUPSWAVEL EZ DIPOLE ANTENNA asse antiq tie Ue D dtRS DIU qq ed d d 10 EVER MENT e FOCDED DIEOLE ANTENNA cesses suet def caeeta pire er driver E i ert pii ee vac rupti aea 24 EAPERUMENT 39 Spic GROUND ANTENNA iet pER IR SER IR ERR MIS RUNE ERR Gund ERR RNIER Gun tausuea tues RN DRE L PUES 35 FARE RIME ME PORE NG ANE ENNA DD 45 EXPERIMENTS 3 Se Ne WA Vee LOOP ANTENNA c misi base beet E Qt asta tli hala R E 54 BPE ME AE E E E EE E EE S alee o m E mM b M ES nee 70 EAPEBLMENTSE T STER I ANTENN
2. cerier of arena tc be verlicsd wilh a rotating EXI amp C IEzeivae Figure5 16 Vertical Polarization Receiving Antenna After click Antenna Initialize in Edi t Menu of a software select H Plane as Plane and click the Auto button for a data acquisition If the data acquisition is finished save in a data box of antenna 1 Observe three radial pattern Set a transmitting receiving antennas again to get an even polarization characteristic respectively The distance between antennas is r 5m Make the surrounding condition to same as the first environment Take the E Plane radial pattern of a full wave circle loop antenna and named Antenna 3 then save in a data box Theoretically except an effect caused by power damage this radial pattern must same as the first pattern If the pattern is differ very much have to do suitably by finding a position where the reflection can be occurred After do suitably continue the experi ment and save new pattern in Antenna 3 data box Click the cursor button on Tool window of computer Two cursors forming the angle of 0 61 respectively are appeared The values arranged on right of screen will be changed These indicate a max value of main beam and a power size dB at cursor s position and an angle and cursor s position is displayed at right bottom of window Select a green cursor by dragging Whenever move this cursor around window the value of cursor 2 is changed This is an amplitude diffe
3. frequency and the rt decide lower frequency The relation of a driving frequency and radius is as below m Afd 7 8 Accordingly the frequency band of antenna is as below c Ec dp x l Uy 4 Ti A T c Spread Speed of Electron Wave in Free Space The spin distance of a spiral antenna from starting point to optional point on antenna is as below ros d E e t e 5 1 7 8 1 2 Radial Pattern The spiral antenna has a circle polarity and bilateral beam pattern and the type of this radial pattern is not changed almost according to the frequency change lf the field polarity of radiational pattern can regards it as a threshold deciding the band width offset and the band width ratio of upper frequency and lower frequency becomes over 20 1 82 P AD dh Figure 7 2 Coordinates System of Antenna and Radial Electron Field EXPERI MENT PROCEDURE l Set the main controller transmtting receiving antenna positioner and computer which are main instruments of the antenna experiment set 2 Set a height control bar on a transmitter and fix 500MHz Yagi antenna on the antenna fixing pack then set this on the polarization control plate In this time set this to be even with earth for an antenna get an even polarization characteristic The transmitting antenna set as Figure 7 3 get an even polarization characteristic Connect the 500MHz oscillation output terminal of main controller and the cable connecting terminal of Y
4. shows the current flowing into a loop antenna in different moment each other In figure to the direction of x axis to be added the current flowing into loop of both half On the other hand to Y axis to be offset a current Accordingly E wave becomes polarized toward X axis With same principle in case of a vertical feed which a loop has a feed point in the upper side or lower E wave becomes polarized in parallel Incase of a even feed whichaloop has feed point in left or right E wave becomes polarized n even 2 4 Impedance Gain Beam width When a size of loop is 1 X the input resistane of Loop antenna becomes a value about 100 Q n this input resistance the input reactance goes down to very small value Under this condition the loop antenna is used very efficiently to be get a proper beam width In this time this loop antenna has a gain about 3 09dB This is less than 3 820B gain of a full wave dipole but larger than 2 15dB gain of a half wave dipole Resultingly theoretically the beamwidth of thisloopantenna is between 47 of afull wave loop antenna and 78 of a half wave di pole It can t say that the circle loop is a cube but almost same as square If feed the antenna at one position since the sine wave is generated to be a current anti node at opposite point to feed point and to be a node at a central points becomes max radiation toward front and rear vertical with earth 57 am o m m E a tmo AA 0M
5. 4 m A Pt A id Lia CERE fd E A A 4Spacing Step Dipole B X 8 Fold and Bend of Both Side C 1 Wave Loop Figure 5 9 Method Thinking the wave Loop Antenna Accordingly it can seems that the square loop antenna in A is what isolate both side of the two folded and bended A 2 doublet as each A 8 to get by spacing 4 The same it can seems that the loop of diamond shape in B is what isolate the antenna of inverted V shape Fteactance 52 tT 8 99 t 341 14 Clroumference Wavel Figure 5 10 Input Impedance of Wave Circle Loop The gain of a full wave loop antenna is different according to thickness of element but a square loop is about dB and acircle loop is some 1 2 2dB Figure 5 10 shows the change of input impedance around resonance frequency of a circle loop When an antenna is tuned the input impedance of a loop using a thin lead is about 1402 Also the tuning frequency is related to the thickness of an element like A 2 dipole but becomes frequency that the entire length becomes a little longer than lwave Also since this loop antenna has a larger range of using frequency than 4 2 dipole when use with a copper wire of some 2m as element loop the length of an element is I2 Xx 1 02 1 03 58 EXPERI MENT PROCEDURE l Set a main controller transmitting receiving antenna positioner and computer which are main instruments of antenna experiment set 2 Set a height controller on a transmitte
6. 4 14 and this le is named the effective wave of half wave dipole The field strength at right angle direction withthe lead of half wave dipole is same as a current of anti node and becomes same as the antenna flowing definitely through the length A 3 14 in Figure 1 9 C The antenna like this is to keep away fromthe condition of infinitesi mal antenna 1 A but substitute S got in the effective wave of half wave dipole in Formula 1 5 and becomes and accord with Formula 1 2 As above the field strength at right angle with lead is settled by current according to the lead and volume 5 of length As Figure 1 5 the antenna excited by harmonics which the length of lead is to multi integer of X 2 is named Harmonics Antenna As an example when use the half wave dipole in 2GHz used for 500MHz it becomes harmonics antenna of 4ti mes Figure 1 10 shows a directivity in free space of harmonics antenna of 2 4ti mes To illustrate the directivity of harmonics antenna in free space use generally this method as follows Make the current of current anti node to same size for each antenna and draw by making the maxi mum radial direction of half wave dipole to 1 for the easy to compare with half wave dipole Figure shows only the right directivity of lead surely left is same shape and the actual cubic directivity becomes a complex cubic forming when rotate in axis of lead 15 he MO XE ed Hall Wiwe Dura Figure 1 10 Directivity of Half Wave
7. Antenna Figure 3 7 shows the A 4 ground antenna This antenna is fed power through hall of a large ground from 50 Qcoaxial cable The size of ground face is important for the design of ground antenna The idea ground faceis unlimited size Actually the ground face of radius 5 Xi s al most ideal ground it must have a minimum radius 0 5 X The ground antenna designs in the set for antenna experiment has a ground face of size 0 5 X Also the coaxial cable feeding to antenna has 50 Q impedance Accordingly take a coupling by making the impedance of A 4 ground antenna to change to 362 The characteristic impedance of a coaxial cable is afunction betweena a radius of central conductor and b distance till central conductor and ground conductor The relation is gi ven as Formula 3 4 Z ef S G When a 0 1595cm b 0 317cm the characteristic impedance becomes 41 5 Q this is a geometric average value of 509 characteristic impedance of coaxial cable and 362 input impedance of A 4 ground antenna MICRO OXDOL SSGUNG PANE b h Figure 3 7 Coaxial Power Feed A 4 Ground Antenna and Ground Face 38 EXPERI MENT PROCEDURE set a main controller transmitting and receiving antenna positioner and computer which are main instrument of an experi ment set for antenna 2 Set the height controller on a transmitter and fix an 500MHz Yagi antenna console fixing pack of an antenna then fix an antenna on follow control plate I
8. On Off SWITCH 500MHz FINE ADJUSTMENT SWITCH 480MHZ 650MHz 26Hz FINE ADJUSTMENT switch 1 85GHZ 2 35GHz 106Hz OSCILLATION OUTPUT TERMI NAL 2GHz OSCILLATION OUTPUT TERMI NAL 0 500MHz OSCILLATION OUTPUT TERMI NAL ee D OO Cc QU A oo m Lr I STEP SMICH LET 2 416 3 12 ORIGIN SWITCH 13 ANTIDI RECTION ROTATING SWITCH 14 NORMAL DIRECTION ROTATING SW TCH 15 l1kHz SIGNAL INPUT TERMI NAL L 2 TRANSMI TTER TTITREILR REEL L1 ile qr caste Tir 277 Ter pT nox Figure 1 3 Transmitter 3 RECEIVER Aneng Firing Fick Sen Fxarization MON Mantra STi ue Pozi n z gawa beg Plate Fasien Genra tia Ti EW Figure 1 4 Receiver 4 ANTENNA FOR TYPE The antenna can be divided into 500MHz 26Hz and 106Hz usages generally 5 Figure 1 4 Antenna for Each Kind Using Quanti E 8 Antenna Type ul i HE Dipole Ant lea 2 GHz Spiral Ant lea Monopole Ant lea Helical Ant lea Horn Ant dea 10GHz Rectangular Patch Ant lea MicroStrip Planar Array Ant Rectangular lea MicroStrip Planar Array Ant Circular lea CHAPTER 2 INSTALLATION amp EXECUTION OF PROGRAM 1 INSTALLATION OF PROGRAM Operate Execution of Start Menu in Windows or execute the program Setup exe in A 2 of Setup Programdiskette using Searcher Only have to terminate the other executing programbefore execute the installation program Indirectory setting screen as below select the insta
9. Polarization Transmitting Antenna Set as Figure 6 13 for Yagi antenna used for receiving get a vertical polarization characteristic T Figure 6 13 Setting of Vertical Polarization Receiving Antenna Click Antenna I nitializein Edi t Menu of a software click the Auto button to data acquisition If the data acquisition is finished after select H Plate as Plane save the pattern in file Keep the 500MHz Yagi antenna used for transmitting to get a vertical polarization characteristic and set as Figure 6 9 for the Yagi antenna used for receiving get a vertical polarization characteristic Click Antenna Initialize in Edit Menu of a software and click again Delete Screen then click the Auto button to data acquisition Observe three radial pattern Set a transmitting receiving antennas get a vertical polarization characteristic respectively The distance between antennas is rzl 5m Make a Surrounding condition of antenna to besame as the first experiment Take the E Planeradial pattern of an Yagi antenna and save in Dummy Plane Theoretically if except an effect caused by a power damage this radial pttern has to be same as the first pattern If the pattern is different very much have to do suitably by finding the position where a reflection can be occurred After do suitably continue an experiment and save new pattern in E Plane TI Click Data Indicating Line in View Menu of upper menu of a data analysis program Two curso
10. Power of H Plane For Angle Take a receiving angle of max power in E Plane pattern and the receiving power in that ti me by using a cursor Confirmif the measured value and the theoretic value are accorded by clicking the Maximum Single Level of E Plane data window Confirmif the taken value by using a cursor and record in below Table 4 3 Table 4 3 Comparison of E Plane with Theoretic Value Taken Value by using a cursor Value by Maximum Receiving Power Single Level Icom Take half angel of a main beam power in E Plane pattern by using two cursors Click the Half Power Beamwidth button Calculate a half power beam width of a drooping antenna in E Plane by using below formula HPbW g a p HPR Wen HPBWael Repeat the experiment of no 18 in radial pattern of H Plane HPBW E Deleteall cursors by clicking adata indicating line in Eduit Menu Compare the experi mental values with a given values in an antenna software If the calculated result isn t accord with these values experiment and calculate again Save the data of E Plane and H Plane and output the result Experiment fromabove no 3 to no 21 with taking the place of a ground plate Large Small based on the experi ment procedure And compare this experi mental result with above result record 52 EXCERCI SE im Where is the using place mainly for a drooping antenna Why so What is the role of four lead placed in each cor
11. Taken Value Receiving Power With cursor Angle Value by Maxi mum Receiving Power Single Level Icom Angle Take a half angle of main beam power in E Plane pattern by using a cursor Click the Half Power Beamwi dth button on data wi ndow to confirmif same the measured val ue with button as taken value with cursor Calculate a half power beam width of spiral antenna in E Plane with below fomaula HPbW g E p HPR Wen HPE Uefi Repeat No 17 of the experiment procedure in H Plane radial pattern HPBW Delete all cursors by clicking the data indicating line in view menu Compare the experi mental values with given value in the antenna software If the calculated result is not accorded to this values experiment and calculate again Save the E Plane and H Plane data and output the result Set the switch in main controller as below 87 500MHz Oscillation Switch off 2 GHz Oscillation Switch on 10 GHz Oscillation Switch off Modulation Switch Mod on 22 Repeat the experiment procedure 8 20 on same spiral antenna fed 2GHz 23 Compare the radial pattern fed each 500MHz and 2GHz to same spiral antenna 88 EXCERCI SE 1 What s the wide band antenna 2 Explain the basic concept for use the spiral antenna as the wide band antenna J Are there the difference between aradial pattern of aspiral antenna and of a di pol eantenna Explain the difference and the reason occurred it 4 Explain the usa
12. The leads of constant length resonate with integral multi high frequency of inherent frequency f Figure 1 4 High Frequency Excitations of Harmonics For the voltage and current distribution on lead current is minimumand voltage is maxi mum at both end and current is maximum and voltage is minimum at point of distance A 4 and it is inversed by periods of X 4 The maxi mimpoi nt of voltage or current is named the anti node minimum point named the node In case of exciting the antenna lead with a standing wave Figure 1 5 shows the method to connect to the current anti node and voltage anti node and that is named the current power feed and this is named the voltage power feed BASS kod fF 3 J Ha a ua Lu reri 2 Pot Feed iA Volage 47 Pao Fork 1 QE Figure 1 5 Current amp Voltage Power Feed of Antenna on Both End Open of Length 1 2 A 3 X2 and the Voltage amp Current Distribution 12 ar a nisr na L Yoltane 2 H5 Sina Maze ndinitegimal ANAT a nran Disrmoublon j Dipalg Electric Dipta Size of Elerib rawe Figure 1 6 Dipole Antenna Figure 1 7 A Center Feed Half Wave Doublet B Half Wave Doublet is a Assembling of Major Infinitesimal Antenna of Different Size In Figure 1 5 indicating the current direction in sometime it have to be considered that the current direction of standing wave adjoining each other becomes inverse 180 anti phase and that the voltage and cu
13. added and subtracted each other The pencil beam radiation pattern is generated in Herical antenna by an effect that the wave progressing form one Loop of open wire to another loop is added each other These are the examples for the driving antenna array effect that is the effect arraying the numerous antenna elements connected with feed circuit by any type Like this it is called the antenna constructed with various antenna element to the antenna array This array effect can be got by using the parasitic antenna element This parasitic antenna element is a conductor or lead which are not connected with feed circuit In this case the array effect caused by the current induced to the parasitic antenna element by an electron wave This parasitic antenna elements becomes excited by Near field coupling radiated from a driving antenna element Launcher 2 Basic Principle of Yagi Antenna Figure 6 6 shows the Yagi antenna having a 6 antenna element ER 0h DIRFCTORBH ELEMENTS DRIVER CLEWENT ATTIVE REFIESTOR ELEMENT Figure 6 6 6 Antenna Element Yagi Antenna The Yagi antenna consists of a constituent as follows Driving Antenna or Radiator connected with a feed circuit As this is an antenna element fed directly froma transmitter can use an antenna element of different type such as a half wave dipole or folded dipole antenna Reflector placed on one side of a driving antenna element Make a radial power to reflect again toward a driving
14. antenna Theoretically can place several reflector with same spacing and length But actually one reflector is accepted generally because of the merits of the reflector over one is not much Director placed on one different side of a driving antenna element It is means that the parasitic antenna elements over one operating connection of a radi al power Actually the several directors are used for the Yagi antenna and it is shorter as 73 distance from a radiator make it to isolate with little shorter spacing The reflector is longer as 5X than a driving antenna element and the first inductor is shorter as 5 The optimum spacing for the Yagi antenna get a max directivity is when the driving antenna element reflector and the first inductor is within 0 15 X 0 25 X respectively When use several inductors the remained inductors is little short and it is isolated with little distance spacing The spacing of a driving antenna element reflector and the first inductors have an effect on an impedance matching But the spacing between antenna elements has not an effect so much on the change The effect of adriving antenna element for a parasitic antenna element nearby is what can induce the current that the phase becomes inverse with the size of an incident wave being same almost for the parasitic antenna elements It has a merits that the antenna gainis increased if have the inductor over one But as increase the number of ainductor the merits is di
15. antenna on a polarization control plate of upper stationary bar to be got a parallel polarization characteristic Set it in center of a rotational axis of a receiver by loosing the position control screw of a receiver and moving the control plate See Figure 4 11 to set 48 Figure 4 11 Setting of Parallel Polarization Receiving Antenna Connect a coupling terminer of a drooping antenna and a RF IN terminal of a receiver with a SMA cable used for Im and connect a OUT PUT 1KHz terminal of a receiver and a Input 1KHz terminal of a main controller with a BNC cable used for Im 4 Calculate the length of a drooping antenna and measure the actual length of an antenna in 500MHz by using below formula and record in Table 4 1 b d di 1 i 5 5 As Figure 4 13 the distance between antennas is isolated as rzl 5m Make the center of each transmitting receiving antenna to be in a straight line at a same height 49 Id Figure 4 13 Distance between Antennas r Set in condition of the power of a main controller as below Power OFF 500MHz Oscillation Switch off 2 GHz Oscillation Switch off 10 GHz Oscillation Switch off Modulation Switch Mod off After set a switch in main controller as below execute the Antenna Trainer Program Power ON 500MHz Oscillation Switch on GHz Oscillation Switch off 10 GHz Oscillation Switch off Modulation Switch Mod on The programwindow s executed make the
16. careless use and in case of modification of performance 2 In case of exceeding the warranted period Onl y in this case we do the parts suppl y for value or repair for value and the period of opposite view is for 5years after finish the warranted CHAPTER 1 INTRODUCTION 1 GENERAL INFORMATI ON AT3200 Antenna experiment system consists of Propagation Pattern and Gain of Antenna and there is each different Antenna of l0types according to the driving style In this RF Source Unit supplying RF current of 500MHz 26Hz 10GHz and Controller which can control the direction of antenna in addition the software which can do a simulation of antenna copying pattern and characteristics by pc interface is offered Since this Antenna Trai ner makes the using frequency to be high itis possible to experi ment On characteristic of antenna propagation in narrow space some 100m J Also moving and custody of System are easy Especially since consists of transmitting amp receiving antenna of telecommunication repeater and the antenna used for receiving of artificial satellite mai nl y the more practical training is possible In particular for Dipole or Yagi Antenna The number and spacing of Element is controlled you can design yourself for directional characteristic and gain La mei Yo cone Lm Figure 1 1 Flow Chart for Experi mental Device on Antenna 2 NOTES Please check the driving procedure and the input power used for this Instru
17. delayed 90 Therefore E ref is added by becoming a same phase with Erad so can see that the electron wave in direction of ahead becomes strong Oppositely for the rear direction since E rad reached froma radiator becomes more delayed 90 than Eref as the first explanation it becomes inverse phase with Eref and is attenuated So when the size of E rad and Eref is same the radiation at rear direction becomes 0 Think like this inthe case of alittle shorter director than A 2 the operation is explained in the same way if consider that the phase of Idir is more precede 90 than E rad Actually the spacing between the radiator and the parasitic element is not always limited as 1 4 Because of the mutual impedance between elements and they give an effect each other it is not simple as above explanation According to the length thickness and spacing between elements the characteristic of an actual antenna is changed compl exi vel y 1 2 Multi Element Yagi Antenna As the original Yagi antenna is an replaced antenna of VHF UHF it is useful to arrange many parasitic elements in the directivity and gain of an Yagi antenna since the physical size is not large so much Only as above explanation if arrange over 4 element the characteristic of an antenna becomes complex as impossible as the exact indication with computer Therefore show the design of the mult element Yagi antenna taken experimentally here Also it is the shape of an antenna w
18. donuts Z a F ll wawvc Pipa y X Liisi 3 t NL Wave Dipole Ar len mM Figure 1 8 Field Directivity of Half Wave Dipole side y z 13 For the comparison indicate the directivity of infinitesimal antenna with dotted line Some is 1 at maximum direction but as a matter of fact in case of half wave dipole it is large as 1 045times The cubic directivity becomes more flatter than infinitesimal antenna rotating around the axis Z The radial resistance of this half wave dipole antenna is calculated like a case of infinitesimal dipole as below and Puh Medal Power o Antenne Nadia Hesiskince _ ae z 23 Cur rint R eceve Value af Coreen Maximnum Porn on Wirel the value is 73 139 In case of center feed as the feed point is a maxi mimcurrent point the radial resistance 13 139 is a simulated load resistance consuming the power as same as radial power in point of power and if ignore the high frequency resistance on lead it becomes same as the resistance of input impedance When the length of lead is just X 2 of wave in free space the radial power in above formula numerator divided into a effective power and ineffective power and ineffective power is to display a reactance for power as a condenser or coil and the val ue is 42 550 in inductive Accordingly the radial impedance of half wave dipole becomes Resistance Element 134 13 Q Reactance Element 42 55 O Inducti ve Like following formula 1 3 show th
19. equivalent each other the radial pattern is same The E Plane radial pattern for a 2 slot antenna excited to same phase and equal amplitude made of multiplying the E Plane radial pattern of a 1 slot antenna by the array element for two elements Accordingly this formula is as below NE sin cos Eyaeenl 7 3 u cos 7 cas d PESE 2 cos d where his a width of slot same as a base material thickness of a patch antenna bis a distance between two slots same as length of a patch antenna id 1 1 Serial Array and Parallel Array The square patch antenna is used as basic element of a microstrip array antenna In this time we will treat two type of array Plane array antenna of type of parallel feed and serial feed The microstrip array antenna consists of some mcrostrip antenna elements and microstrip feed Circuit The feed circuit consists of the manual elements such as power distributor and transmitting line as well as the active elements such as phase shifter amplifier launcher and frequency mixer etc The feed line is connected to the radial element directly and gi ve not an effect on the radial pattern directly The best merits of a microstrip antenna is what can etch the arrayed antenna on one base material as well as feed line That is can contain various elements to antenna with low price The array antenna i5 very thin and can contain numerous elements so it can achieve to high effect The other merits of array antenna i
20. is easily got that unfold denominator numerator by power series and take limit to UV Dividing formula 12 3 by maxi mum val ue you can get the normalized array factor f W of N element arranging antenna which is considered fixed space and identical value and phase center is located in the starting point m Sin LAT Be KB N sint277 12 4 125 FIGURE 12 2 A 4 Array Factor for Element Arranging B Radiation Pattern for d A 2 Figure 12 2 A gives normalized array factor This figure represents answer of arranging antenna as function of phase difference W between elements near arranging antenna When the phase difference is 0 1 e when signalling power is located on the broadside answer is the maximum Figure 12 2 B used diagrammatic method which indicates radiation pattern of antenna by polar coordinate Figureis described half circle which radiusis Bd For example when the interval of element is A 2 the radius becomes bo Lleida S aT After drawing half circle fromeach points inthe figure which indicate array factor by figure to the half circle draw a vertical line down From the crossings between each vertical line and half circle to the starting point of the circle draw another lines down Then along this segments of the lines you make a point selecting points part from the starting points as same Length as width of the array factor For example when W 7 2 array factor is 0 so in the polar coordinate point correspo
21. on a displayer will be changed with the cursor of same color moving These indicate a position angle of cursor anda receiving power in that ti me by dB and the angle between cursors and difference of power is displayedon2 displayer Record the taken val ues in Table 2 2 Table 2 2 Receiving Power for Angle Recei vi ng Power of E Plane For Angle Recei vi ng Power of H Pl ane For Angle Take an angle which the maxi mum power is received in E Plane pattern and a receiving power in that ti me using the a cursor Click the Maxi mimSi ngl e Level button on a E Plane data windowand confirmif the measured value is same as ataken val ue by using the cursor 32 18 13 20 21 21s then record in below Table 2 3 Table 2 3 Comparison of E Plane and Theoretic Value Taken Val ue Receiving Power m i Value by Maximum Receiving Power S single Level Icom angle PO Take a half angle of a main beamsize in the E Plane pattern by using two cursors Click the Half Power Beam Width button on the E Plane data windo and confirmif a measured value and the taken value by using a cursor is accord Calculate a half power beamwidth of a folded dipole antenna in E Plane by using below formula HPBW 9mm penus HPB Repeat the 18th experiment procedure in a radial pattern of H Plane HPBW z Delete all cursors by clicking a data indication line in Edit Menu Compare the experimental value with the values taken fr
22. point of front horn and the center of antenna used for receiving to be in straight line Figure 10 12 Setting of Single Patch Antenna Click Antenna lnitializein Edi t Menu of asoftware click the Auto button to data acquisition If the data acquisitionis finished after select H Plane as Plane save the pattern in file Keep the Horn antenna used for transmitting to get a vertical polarization characteristic and set the horn antenna used for receiving to get a vertical polarization characteristic as Figureld 10 Click Antenna Initialize in Edit Menu of software and click again Delete Screen then click the Auto button to data acquisition Observe three radial pattern Set a transmitting receiving antennas get a vertical polarization characteristic respectively The distance between antennas is r l 0m Make a surrounding condition of antenna to be same as the first experiment Take the E Plane radial pattern of a single patch antenna and save in Dummy Plane Theoretically if except an effect caused by a power damage this radial pattern has to be same as the first pattern If the pattern is different very much have to do suitably by finding the position where a reflection can be occurred After do suitably continue an experiment and save new pattern in E Plane Click Data Indicating Line in View Menu of upper menu of a data analysis program Two Cursors Blue White used for E Plane and tow cursors Yellow Green used for H P
23. resonance frequency and the reflected loss Measure received signa circling 360 antenna which will be measured at the I m distance fromstandard horn antenna Figure 12 7 shows the gain according to the frequency of standard gai n horn antenna DGB 520 128 Elandard Gain Horn DBG 520 Galin iB 8 4 10 11 12 13 Frequency GHz FIGURE 12 7 Standard Gain Horn Antenna DGB 520 Figure 12 8 is the result that measure radiation pattern of single circle arranging antenna made of 8 elements Operating frequency of antenna is 10 CHz gain is 13 1 dBi 3 dB beam width is about 12 on the H plane and about 14 5 12 on the E plane Also maxi mimsize of sub lobe represents 11 4 dB on the H plane and 7 5 0B on the E plane FIGURE 12 8 Radiation Pattern of Circle Arranging Antenna 8 el ement 129 EXPERI MENT PROCEDURE 1 Set maincontroller whichis main equipment of antenna experiment set receiving transmitting antenna positioner and computer 2 Fix the 106Hz Horn antenna on the polarization controlling plate of transmitter Set horizontally to the ground in order to have horizontal polarization characteristics Like figure 12 9 installed transmitting horn antenna bearthe character of horizontal polarization Connect 500MHz launching output terminal of main controller and cable connecting terminal of horn antenna by SMA cable for 2m FIGURE 12 9 Horizontal Polarization Transmitting Antenna 3 Fix
24. selected by software open the cursor option then select a pattern you want Select the Options Set Cursors at 3dB item The cursor will be placed automatically Use this item to take fast the approximate value of a half power beam width in the next experiment If you necessary can adjust the to be high accuracy 34 Save the data and output the result In output have to present the radial pattern of two data box Full Wave Diamond Loop Antenna 35 Fix a full wave diamond loop antenna to be got an even polarization characteristic on a polarization control plate of receiver Use the positon control plate of receiver to place an antenna in rotating center of receiver See Figure 5 21 to set Figure 5 21 Even Polarization Receiving Antenna Connect the cable connecting terminal of a full wave diamond loop antenna and RF IN temainat of receiver with 5MA cable used for Im and the OUT PUT 1KHz terminal of 65 receiver and the I nput 1KHz terminal in receiver of a main controller with BNC cable used for Im 36 Use belowformula to calculatea length of afull wave diamond loop and measure actual length 4Q 4 of an antenna in 500MHz then record in Table 5 3 A c5 L Zxr Table 5 3 Length of Full Wave Diamond Loop Antenna cm Tile distance between antennas is isolated as rzl 5m as Figure 5 22 Make the center of a transmitting receiving antennas to be in straight line of same height each other Figure 5 22 Distan
25. sine wave having a phase difference of 90 for X Y axis input by Osiloskov Another way is what send the electron wave along the helix lead of proper size Since the wave move along helix make the field rotating rapidly This principle is applied to the helix antenna The rotation of field is one of clockwise and counterclockwise If the field rotate to right finger when the thumb indicate toward traveling direction by grasping right hand this polarization is called right circular polarization If opposite direction it is called left circular polarization The cross polarization isolation in circular polarization weigh heavily The right circular polarization antenna 90 can not receive the signal to be left circular polarized The inverse also is effected But each antenna get offset a little the signal to belinear polarized toward optional direction and can receive Although the linear polarization is used in major case the circular polarization would be used very usefully according to the communication system For one example it is difficult to maintain a direction of antenna regularly in the satellite communication system Accordingly the linear polarization in this case becomes receive a fading If use a circular polarization the strength of receiving signal becomes regular almost regardless a direction of satellite antenna 2 Herical Antenna Figure 8 1 shows a typical axial mode of a herical antenna That is the herical antenna is
26. taken radial pattern to Antenna l and save in data box as E Plane Toconfirm radial pattern exactly usea data box If adjust MSP Max Signal Position to 0 can see the radial pattern of this antenna Make a Yagi antenna used for receiving to rotate 90 the polarization control plate to be 63 got a vertical polarization characteristic Don t change the polarizing direction of asquare loop antenna used for receiving Experiment again and named Antenna 2 then save this radi al pattern as E Plane Figure 5 19 Vertical Polarization Transmitting Antenna 27 Set a full wave square loop antenna used for receiving to be got a vertical polarization characteristic as Figure 5 20 Wake ihe cemer o areia te verli al wid a rotatiricy axi vc peer Figure 5 20 Vertical Polarization Receiving Antenna 28 After click Antenna Initialize in Edit Menu of a software select H Plane as Plane then click the Auto button for a data acquisition The data acquisition is finished save the pattern in Antenna 1 as file 29 Observe three radial pattern 30 Set again the transmitting receiving antennas to be got an even polarizat characteristic The distance between antennas is r l 5m Make the surrounding condition of antenna to same as the first experiment Take the E Plane radial pattern of afull wave circle loop antenna save in the data box Theoretically if except an effect caused by power damage this radial pattern must same as
27. the first pattern If the pattern is difference ver3 much have to do suitably by finding a position where the reflection can be occurred After do suitably continue an experi ment and save new pattern in Antenna 3 data box Click the cursor button on tool window of a computer Two cursors making angle of 0 each other are appeared The values arranged at right side of screen will be changed These indicate the max value of a main beam and the power size of cursor position dB and the angle and cursor position is displayed in the right bottom of the window 64 Select a green cursor by dragging Whenever move this cursor around window the value of cursor 2 is changed This is a difference of amplitude dB between max value of a pattern and a cursor position 3l Use two cursors to take a half angle of main beam power size in E Plane of a data box Calculate a half power beam width in E Plane of a full wave square loop antenna with below formula HPBWz ypawen upEWaw 32 Repeat 29th experiment procedure in a radial pattern of the third data box HPBW p 33 Close an option of cursor Window return to the initial screen Compare the experi ment al values with give values of an antenna software If the calculated result is not accorded to these values experiment and calculate again Ref The position of a hal wave beam width take with antenna software though it stray fromright 3dB point To observe the cursor s position
28. the two dimensional arranging antenna on polarization controlling plate of receiver horizontally to the ground in order to bear the character of horizontal polarization Place antenna on the circling center of antenna receiver using position controlling plate Install referring figure 12 10 Figure 12 10 Installion of Horizontal Polarization Receiving Antenna Connect the cable connecting terminal of circle arranging antenna and RF IN terminal of 130 9i receiver by SMA cable for Im And connect output 1KHz terminal of receiver and receiving section input 1KHz terminal of main controller by BNC cable for Im Measure length of the circle arranging antenna and record on the table 12 1 TABLE 12 1 Length of antenna and feeder mm NENNEN Length of Antenna E ER MEEMEEMEMEMNMNMSZSZSZIE a E Like figure 12 11 distance between antennas is isolated by r lm Install the horn antenna for transmitting and the single patch antenna for receiving horizontally and to face each Other At this time put the front section horn section square center of horn antenna and the center of single patch antenna in a straight line Ep ei i i Figure 12 11 Distance r Between Antenna 6 Set like below in the condition of power is off ig Power off 500MHz launching switch off 2 GHz launching switch off 10 GHz launching switch off Modulating switch Mod off Execute the antenna trainer program after setting switch in the
29. to file Use a data box to confirmthe radial pattern Set MSP Maxi mum Signal Position to 0 can see a radial pattern of antenna exactly 10 Set an 500MHz Yagi antenna used for receiving at right angle with ground by rotating 90 the polarization control plate with Spinning a fixing bolt attached to polarization control plate to get a even polarization characteristic 11 Set as Figure 1 16 for the k 2 dipole antenna used for receiving get a even polarization characteristic Here set the antenna at right angle with a rotating axis by loosing the control screw and moving the position control plate 19 Flxira Boll Figure 1 15 Setting of a Even Polarization Transmitting Antenna Figure 1 16 Setting of an even polarization receiving antenna Reference According to the position of a receiving cable it can be the case that the partial of transmitting signal is received through a cable During experiment the radial pattern have to control the position of connected cable to a receiving antenna to prevent the error by this effect Have to make an effort to maintain ashort length of cable connecting the receiving antenna and main control period Have to set to be placed near a mast cable with maintaining symmetry 12 Keep the drawing pattern of E Plan after click again the antenna initial state in the edit menu of the software select H Plane as Plane and click the Auto button for a data acquisition Completed the data acquisition
30. ub EHH 3 i m 05 EN ii i E n E T 8L RI TAI a a ui eri LO H a NETT CERE hel TT TTT iu pal EE Scere ae A Rae 45 mn fds Bit Figure 2 3 Impedance Change Figure 2 4 Impedance Change of ZLine Type Folded Dipole of SLine Type Folded Dipole 2 Impedance Matching For the most suitable power transmitting it must same the power impedance as load impedance Figure 2 5 indicates the simple circuit of power voltage Vs internal resistance Rs and load resistance RL The maximum power transmitting is generated when R Ri Fig Va FAL Rg Figure 2 5 Impedance Matching between a power and load for the maximum power transmitting The same ruleis applied for the antenna system For the maxi mumpower transmitting the antenna input impedance Z must same as a transmitting lead or waveguide impedance Zi as Figure 2 6 When the transmitting lead and antenna don t match completely instead of the partial transmitting power is radiated through an antenna it is returned by reflecting In case of the receiving antenna the partial power received by antenna isn t transmitted to receiver and re radiation will be occurred through a receiving antenna When impedance non matching Figure2 4 shows the relational formula between power transmitted through impedance nonuniform point and the reflected power ddr TIER I n aaa REGEN ER i EL TAFISMISEICIN L WE Gt NEL IGE ARTE A Figure 2 6 Impedance at a tra
31. without fold by being divided as same length as Figure 5 2 In this figure it can be seen to have a current distribution like a cosine wave has a max value at power feed Figure 5 3 shows the distribution of a circle loop antenna and how get the electromagnetic field generated along this is added and offset The electromagnetic field radiated in this case get add in direction of Y Y and Z Z but get offset in direction of X X Y Inznoasng Magnat Drecian th 44 d 4 sg FLAME 7 CUPPENT DISTRIBLITICIN Bn LP wor CUm er x x i T Enocoas Oats uir me CAL Gee d T2H5sin n PAagnotiz Bagali Diraz inn Minoon 0 B T zneaainuj Magnetic tr Um g od jreciior TERT Figure 5 3 Current Distribution of Circle Loop Antenna 2 2 Radial Pattern of Full Wave Loop Antenna There are 3 important plane in a loop antenna That is E Plane H Plane and Loop Plane Contained in antenna To explain this plane let us consider a square loop antenna Y Aaxl A A S Figure 5 4 Square Loop Antenna 55 Theloopantenna is placed to be parallel in front of you on X Y Plane and Zaxis is placed toward you as Figure 5 4 Compare a loop with a central feed dipole X Z plane is E plane Y Z plane is H plane and Loop plane is X Y plane cb d A B Figure 5 5 A E Plane Radial Pattern B To Measure a E Plane of Full Wave Loop Antenna Radial Pattern must Rotate The theoretical radial pattern in E Plane X Z
32. 4 Figure 5 24 Vertical Polarization Receiving Antenna 44 After click Antenna Initialize in Edit Menu of a software select H Plane as Plane then click the Auto button for data acquisition If a data acquisition is finished save the pattern in Antenna 1 as file 45 Observe three radial pattern 46 Set again the transmitting receiving antenna to be got an even polarization characteristic The distance between antennas is rzl 5m Make a surrounding condition of antenfia to same as the first experi ment Take the E Plane radial pattern of afull wave diamond loop antenna and save in data box Theoretically except an effect caused by power damage this radial pattern must same as the first pattern If the pattern differ very much have to do suitably by finding a position 67 47 48 49 where the reflection can be occurred After do suitably continue the experi ment and named the new pattern to Antenna 3 then save in data box Click the cursor button on tool window on computer Tow cursors making the angle of 0 are appeared The values arranged on right side of a screen will be changed These indicate the max value of a main beam and a power size dB at cursor position and the angle and cursor position is displayed in the bottom of window Select the green cursor by dragging Whenever move this cursor the Value of cursor 215 changed This is a difference of amplitude between max value of the pattern and cursor position
33. 8 in 1901 Marcon succeeded the crossing telecommunication of Atlantic by finding the antenna so the electric wave was to be used in telecommunication It is a ground antenna that used in that time so it is used to call Marconi Antenna The ground antenna is a representative initial antenna and it is used majority for a long wave an medi um wave antenna 1 Ground The ground antenna is an antenna contacted a output terminal in transmitter out one axis of power feed lead to the earth The power feed for this antenna is fee between earth and antenna conductor as Figure 3 1 vatia Type Inverse L Tyu Toe pee Fath m Figure 3 1 Representative Ground Antenna In case of aA 2 dipole antenna in different froma ground antenna connect the both end of a high frequency source Generally in case of a folded antenna the length of a conductor may shorter a A 2 than non ground antenna it has a merit that it is easy to match if a power feed point is low But since a returning road of antenna current pass earth it has demerits that the antenna efficient go down as a damage is large caused by ground resistance if a ground is insufficient 2 VERTICAL GROUND ANTENNA Let s think the case of the conductor length is A 4 four first frequency Suppose that the earth is complete conductor flat it is equivalent to X 2 dipole in free space because can consider a image antenna of length 4 4 as Figure 3 2 n mage Antenna 77 ww 35 Figure 3 2 Power Dist
34. A cueesboeta side naeh outbound e E botas EE OE E E EOE 81 PAPERI MENTO a0 BEBO Alle TAIN HEIN gae e HRS SNO TUS NER bU MER MES MER MEME MEE ME UEM 90 ERPE RLMEN TO ed EAS 200 ORE ANTE NN A assess cute EEO du RN EO eR o RU dus p Rud dup du du RUE 99 EXPERIMENT SLUNG PANCA ANTENNA ue casa traf ridic ites cai oid eiie onte erat teer netus 107 EAPERUNENTS SE T OU MEN SIMON ARRAY ANTENNA Iiis un eei tonos uo Nocte nodu RIP te iodeib e 117 BAER MEN Oe 2 SOL EE ARRANGING ANTENNA scan toni hae mit del im itotao a d Rh to cA EU dod hito 125 WARRANTY AND EXTENDED SUPPORT THIS SHENZHEN ATTEN ELECTRONICS CO LTD PRODUCT IS WARRANTED We warrant the quality for the period of two years frompurchasing date so please contact either SHENZHEN ATTEN ELECTRONICS CO LTD directly or the dealer where the instrument is purchased as possible for the details of the warranty service or repair in this period EXTENDED SUPPORT Please read this manual before use this instrument and especially note below items l Know well the management and using of this instrument based on details of Manual before use 2 Make sure before connect if the selected input voltage 220V of this instrument is same as the power voltage 3 Make sure correct fuse of rated voltage is used AC 250V 1A 4 Shall do the installation and check depend on Manual 5 SHENZHEN ATTEN ELECTRONICS CO LTD will not be responsible for the below case 1 In case of the damage due to misuse or
35. ATCHES FOR THE 5MA COAXIAL CABLE CONNECTOR Figure 10 8 Single Patch Antenna Unit mm 111 EXPERI MENT PROCEDURE l Set a transmitting receiving antenna positioner and a computer which are main instrument of an antenna experimental set 2 Fix 106Hz Horn antenna on the polarization control plate in transmitter Set it to be even with earth to get an even polarization characteristic The transmitting Horn antenna as Figure 10 9 gets an even polarization characteristic Connect 10GHz oscillation output terminal in main controller and Cable connecting terminal of Horn antenna with SMA cable used for 2m Figure 10 9 an even polarization characteristic 3 Fix the Horn antenna on the polarization control plate in receiver to measure an axial mode radial characteristic Use the position control screw in receiver place the ground plane to be vertical with a rotary axis in receiver See Figure 10 10 to set Figure 10 10 Setting of Even Polarization Receiving Antenna Connect the single patch antenna and RF In terminal of a receiver with SMA cable used for Im and connect OUT PUT IKHz terminal of a receiver and Input KHZ in receiver of main controller with t3NC Cable used for Im 4 Measure the length of a single patch antenna and record in Table 10 1 112 Table 10 1 Length of Antenna mm Actual Length of Antenna 5 AS Figure 10 11 the distance between antennas is isolated as rzl m Set the horn antenna used fo
36. Angle 17 Using cursor get theangleandreceivingelectric power at that ti me being received maxi mum electric power on the E Plane pattern Record on the table 12 3 that being identified value being measured putting Maximum Single Level button of E Plane data window and value being obtained using cursor TABLE 12 3 Receiving electric power Comparison of angle Taken Value With cursor Value by Maximum Receiving Power Single Level Icom Angle 18 Using two cursors get the angle being half of electric power magnitude of main beam Confirm 13 that it is identical which value being measured putting Half Power Beam width button of E Plane data window and value being obtained using cursor Figure the half electric power beam width on the E Plane of circle arranging antenna HPBWg upwen HPBen 7 Repeat experi ment order No 18 by the radiation pattern of t Plane HPBWi Eliminate all cursor clicMng data indicating line of view menu Compare experi ment val ues with values being given in the antenna software If the results of calculation isn t identical with this values experiment and figure again 133 21 Save data of E Plane and H Plane and output result EXERCI SES Mean to power feed micro strip patch antenna 8 having input impedance 120 by coaxial cable having characteristic impedance 50 Q on the circle arranging antenna At this case design A 4 impedance converter for 4 position 2
37. Draw layout in case of circle arranging the micro strip patch antenna 16 for 10 GHz 3 Compare and explain that radiation patterns of the single micro strip patch antenna with the circle arranging antenna 4 Get the gain of mcro strip antenna which the micro strip patch antenna 16 for 10 GHz is circle arranged 5 What is the polarization character of circle arranging micro strip antenna 134
38. Full Wave and Harmonics harmonics is increased in Figure get near to the direction of lead As the multiple of in Figure 1 11 Full wawo Ardens Gaulle herl pF X SE uf l l T j Lo i j ATirmpgs e Times A High Frequent ADE is occurred to right angle direction with lead Redi al 2Ti mes 90 2 5 Times 121 Q EXPERI MENT PROCEDURE Resistance of Harmonics Antenna Current Anti 3 Times 100 2 6 Ti mes 126 2 Node becomes 4 Times 114 Q 7 Ti mes 131 Q ay 4 alin Bl The 5 Angle balen hi lead a mazim d direc Lc Ta o Langli ot mBadkWaye X Figure 1 11 Relation between Lenth of Harmonics Antenna and Maxi mum Radial Direction 16 AT mes the direction growing the maxi mumradi ation and indicate the relation between the spacing angle and length Also Figure 1 10 shows the directivity of center power feed antenna of wave by the way this antenna becomes same shape as right and left sine wave current isn t named harmonics antenna but full wavelength wavelength since the maximum radiation SETTING OF EXPERIMENT APPLIANCE l Set the main controller transmitting amp receiving antenna positioner and computer which are main appliance of antenna experi ment set Set the height controlling bar of a transmitter and fix the 500MHz Yagi antenna fixed on antenna fixing pack to the polarization control plate attached a controlling bar And set the antenna a
39. GHz Oscillation Switch off Modulation Switch Mod off After set a switch in main controller as below execute the Antenna Trainer program Power ON 500MHz Oscillation Switch off 2 GHz Oscillation Switch off 10 GHz Oscillation Switch on Modulation Switch Mod on The program wi ndow is executed execute Data Acquisition in Pop Up menu Here after select Antenna select E Plane as Plane and control to be displayed 0 in gain displayer by adjusting the signal attenuation The adjustment is completed start Acquisition If the data acquisition is completed save the taken radial pattern in file Use the data 103 10 EY 3 2 Pr I box to confirma radial pattern exactly If set MSP Max Signal Position to 0 can see the radial pattern of this antenna Make the control plate to rotate 90 for the 10GHz Horn antenna used for transmitting get a vertical polarization characteristic Figure 9 6 Setting of Horn Antenna Set the Horn antenna used for receiving as Figure 9 6 to get a vertical polarization characteristic Click Antenna Initializein Edi t Menu of a software click the Auto button to data acquisition If the data acquisitionis finished after select H Plane as Plane save the patternin file Keep the 10GHz Horn antenna used for transmitting to get a vertical polarization characteristic and set the horn antenna used for receiving to get a vertical polarization characteristic Click Antenna In
40. Plane is as Figure 5 5 A To measure this radial pattern the loop must be rotated toward Y axis as Figure5 5 B Y A IRI Figure 5 6 A H Plane Radial Pattern B Rotation to measure of Full Wave Loop Antenna H Plane Radial Pattern To measure a radial pattern of H Plane x y plane indicated in Figure 5 6 A a loop must be revolved on x axis as Figure 5 6 B RBH AI SED Figure 5 7 A Loop Plane Radial Pattern B Rotation to Measure a Loop of Full Wave Radial Pattern Plane Radial Pattern 56 Finally to measure a radial pattern of Loop plane x y plane indicated in Figure 5 7 4A the loop must rotated on z axis as Figure 5 7 B Let us consider more exactly the theoretical radial pattern of E Plane H Plane and Loop Plane expressed in each Figure 5 5 A 5 6 A and 5 7 A The radial pattern is similar the E Plane and Loop Plane but the amplitude of a radial As Figure 5 6 the electromagnetic field in center of loop is appeared very strongly as to be a composition of electromagnetics occurred by phase current But on Y axis outside of a loop the electromagnetic field becomes more stronger but there is a little phase difference The electromagnetic field of a loop plane becomes smaller than E plane electromagnetic field 2 3 Polarization y y POII ARIZATICN X x CURRENTS CANCEL w Wey x POLA 44 71M x PCA ARIAT CURFPCAITS LAIBRFNTSE ADD LP AF IL Figure 5 8 Polarization of E Plane in x Direction Figure 5 8 A B
41. Use tow cursors to take an half angle of main beam power size in E Plane pattern of a data box Calculate a half wave beam width in E Plane of a full wave diamond loop antenna with below formula HPBWz ypawen upEWaw Repeat No 44 of experiment procedure in radial pattern of the third data box HPBW p Close an option of cursor Window return to the initial screen Compare the experi mental values with the given values if the calculated result is not accorded to these values experi ment and calculate gain Reference The position of a hal wave beam width take with antenna software though it stray from right 3dB point To observe the cursor s position selected by software open the cursor option then select a pattern you want Select the Options Set Cursors at 3dB item The cursor will be placed automatically Use this item to take fast the approximate value of a haft power beam width in the next experiment If you necessary can adjust the to be high accuracy 50 Save the data and output the result In output must shows the radial pattern of two data box 68 EXERCISE Express the current distribution raging along lead of afull wave loop antenna by drawing 2 Make clear that the infinitesimal loop antenna and the infinitesimal loop antenna is duality 3 Try to draw the radial pattern the circle square and diamond full wave loop antenna respectively and explain the difference 3 Explain what is the polar
42. a as Figure 8 5 gets an even polarization characteristic Connect 106Hz oscillation output terminal in main controller and Cable connecting terminal of Horn antenna wi th SMA cable used for 2m Figure8 5 Setting of Even Polarization Horn Antenna Fix the Herical antenna on the polarization control plate in receiver to measure an axial mode radial characteristic Use the position control screw in receiver place the ground plane to be vertical witha rotary axis in receiver See Figure Figure8 6 Setting of Axial Mode Herical Antenna Connect the Herical antenna and RF In terminal of a receiver with SMA cable used for Im and connect OUT PUT 1KHz terminal of a receiver and Input 1KHZ in receiver of main controller with BNC Cable used for Im Use below formula calculate the length of Herical and measure the actual length of Heri cal then record in Table 8 1 The exact oscillation frequency of RF signal generator is 106Hz aS Table 8 1 Length of Antenna cm Theoretic Length of Antenna Actual Length of Antenna EN o A To be Decided by Number of Antenna S As Figure 8 7 the distance between antennas is isolated as rzl m Set the transmitting receiving antennas at opposite position of same height Make the center of a hel i x conductor of herical antenna and the center of square horn part of a horn antenna to place in straight line 94 Figure 8 7 Distance between Antenna r 6 Set as below in condition of turning off the pow
43. a length and thickness of conductor 200 Pt ttt tt TT PL Tt TT E NL fd d HHH TTT IU ANL e Fre AEC ees a O O S M O O saa L A S E B n eT non eee ai He D J m Por i I LLL LAE EM FARE au iud Ex J SLS eem Feet cL E An ddl Baik SeeeP see eee Point S nes vo Lil Tat NT UA an AS ey eo ie 0 CCRC E i F E zx Bi OF Un 02 aa 94 OE Dp 07 Moi ba GJ M 4 amp D D7 Length Wawe of Antanna L ngthWave of Amanna Figure 3 4 Power Feed Point Impedance of Vertical Ground Antenna X 4 Ground Antenna 36 The A 4 ground antenna is equivalent to a 2 vertical dipole antenna by earth complete conductor Figure 3 5 shows ideal pattern of an even and a vertical directivity of this antenna The vertical directivity is about below45 very low Also even directivity is non directivity as if radiate the electric wave equivalently to all directions Since the power feed point impedance of this antenna is 36 Q can use a coaxial cable of 50 OQ as a power feed lead but put a gamma match or element one more in parallel to use for good matching Take the element length of antenna from below formula To on A MHz But this is theoretical in actual antenna by considering an uniaxial ratio take with below d Figure 3 5 shows the case that a 4 ground antenna is on the face of a complete conductor This is a half length of a X 2 or half wave dipole ES iato LA YPIvRsICal Exoression Bitacal Patter
44. adial pattern of a Horn antenna Let s calculate a half power beam width of a horn antenna BASIC STUDY 9 1 Pyramidal Horn Antenna The pyramidal horn antenna is one type of antenna used very much Figure 9 1 shows the geometry model A Geometry Structure B Section of H Plane C Section of E Plane Figure 9 1 Pyramidal horn Antenna The waveguide can spread a shape of numerous modes of electron wave that is 3 dimension passing into waveguide Each mode consists of unique own electron field If the opening angle of a pyramidal antenna is small sufficiently only the dominant mode of waveguide has a mean Other modes can be spreaded by being evanescent mode The flux line of main mode is expanded into the cylindrical type with a sector horn antenna and into global type with a pyramidal horn antenna Figure 9 2 shows the shape We BAGEL T Figure 9 2 Phase Error by Wave Front of Horn Antenna A 99 As above figure the wave front is not plane but curved surface This is the cause induci ng the phase error can beconsidered in analysis of antenna characteristic The phase error is indicated by generalized route error that is s and t AR E E _ 7 JEP n where s and t are generalized route error is wave A B Leand LH are values given in Figure 9 1 The approximate gain of a pyramidal horn antenna can be calculated by Formula 9 3 CD aj AM B Juhi ws ee 9 3 where LzandLn are adamage value by phase err
45. agi antenna with SMA cable used for 2m ELE GRC Ge Figure 7 3 Even Polarization Transmitting Antenna 3 Fix the 500MHz Yagi antenna to get an even polarization characteristic on the polarization control plate of a receiver Use the position control plate of a receiver to place an antenna in rotating center of a receiver See Figure 7 4 to set Figure 7 4 Setting of Even Polarization Receiving Antenna Connect the Yagi antenna and RF In terminal of a receiver with SMA cable used for Im and connect OUT PUT 1KHz terminal of a receiver and Input 1KHZ in receiver of main 84 4 CO controller with BNC Cable used for Im As Figure 7 5 the distance between antennas is isolated as r 1 5m Set the transmitting receiving antennas at opposite position of same height Figure 7 5 Distance of Antennas r Set as below in condition of turning off the power of main controller Power OFF 500MHz Oscillation Switch off 2 GHz Oscillation Switch off 10 GHz Oscillation Switch off Modulation Switch Mod off After set a switch in main controller as below execute the Antenna Trainer program Power ON 500MHz Oscillation Switch on 2 GHz Oscillation Switch off 10 GHz Oscillation Switch off Modulation Switch Mod on The program wi ndow is executed execute Data Acquisition in Pop Up menu Here after select Antenna select E Plane as Plane and control to be displayed 0 in gain displayer by adjusting the signal attenu
46. amand select the antenna type then select E Plane as Plane and control to be displayed 0 onthe antenna gain displayer by controlling the signal attenuation If the control is completed start data acquisition 9 The data acquisition is completed save got radial pattern into file Use a data box to 30 see a radial pattern exactly Set MSP Maxi mum Signal Position on 0 can see a radi al pattern of this antenna 10 For the 500MHz Yagi antenna used for receiving get an even polarization characteristic set the polarization control plate to the right angle position with ground by rotating 90 as Figure 2 13 Figure 2 13 Setting of Even Polarization Transmitting Antennana 11 For the folded dipole antenna used for receiving set by losing the position control screw and making a polarization control plate to rotate 90 and then setting it fitting the center of antenna in center of a rotational axis of receiver And make the center of Yagi antenna used for transmitting and center of folded dipole antenna used for receiving to parallel each other Z Figure 2 14 Setting of Vertical Polarization Receiving Antenna 12 Keep the drawn pattern in state of E Plan and after click Initialize in edit menu of software select H Plane as Plane and then click a Auto button for data acquisition The data acquisition is completed save two drawn pattern file 13 Keep the 500MHz Yagi antenna used for transmitting to get a vertical pola
47. ame color This shows the position angle of cursor and the receiving power in this time by dB and shows the angle between cursors and the difference of power in below displayer Record the taken value in below 3 2 Table 3 2 Receiving Power for Angle Receiving Power of E Plane For Angle Receiving Power of H Plane For Angle Take the angle received a maximum power in E Plane pattern and receiving power in that ti me by using a cursor Confirmif the measured val ue by pressing the Maxi mum Single Level button on E Plane data window and the val ue taken by using cursor are accorded and record in below table3 3 42 Table 3 3 Comparison of E Plane and Theoretic Value Taken Val ue Receiving Power by using a cursor Angle PO Value by Maximum Receiving Power S O Single Level Icom Angle Take a half angle of a power size of main beam in E Plane pattern by using two cursors Confirmif the measured value by pressing the Half Power Beam wi dth button on E Plane data window and the value taken by using cursor are accorded Calculate the half power beamwidth in E Plane of k 4 ground antenna by using below formula HPHW urupe yemtiem HPBW Repeat No 18 in this experiment procedure with the radial pattern of H Pl ane HPBW Delete all the cursors by clicking the data indicating line on View Menu Compare the experimental values with the given value in antenna software If calculated result is no
48. arization with a herical antenna If measure max and min amplitude by rotating one antenna the axial ratio can be calculated with two amplitude ratio directly Ideally the herical antenna take a value between axial ratio 1 and 1 1 0 and 0 83dB To take these result must make the open end of helix to growless little by little It is not easy to get an axial ratio of some 1 12 1dB for the helix of an actual regular diameter if indicate the gain of a herical antenna based on experi ment as below ive 219 1 0 5 EET G 8 3 42 AB p mda 3 4 Normal Mode The herical antenna taking the different radial pattern entirely can be made as Figure 8 4 This herical antenna is driven with normal mode the max radial direct is vertical with an axis of antenna In normal mode driving the circumference of helix must less in proportion to the wave Because make the current to distribute into the phase and amplitude almost identically along helix The helix of this type has a low electric length and low efficiency A Geometric Structure B Radial Pattern Figure 8 4 Normal Mode Herical Antenna 93 EXPERI MENT PROCEDURE l 2 J AL 2 Set a transmitting receiving antenna positioner and a computer which are main instrument of an antenna experimental set Fix 106Hz Horn antenna on the polarization control platein transmitter Set it to be even With earth to get an even polarization characteristic The transmitting Horn antenn
49. atinglineinviewmenu Compare the experi menta values with given value in the antenna software If the calculated result is not accorded to this values experi ment and calculate again 21 Save the E Plane and H Plane data and output the result 22 After remove L1 L2 L3 in Figure 6 10 and make 3 element antenna complete below table by repeating item 1 21 Table 6 5 Characteristic of 3 Element Yagi Antenna Regeng Power Maximum Single Level Angle Hail Power Beam Width 78 After couple L3 in Figure 6 10 and make 4 element Yagi antenna complete below table by repeating item 1 21 Table 6 6 Characteristic of 4 Element Yagi Antenna Maximum Singha Level Hal Fowar seam vidin e e n m c omo Receiving Power After couple L2 in Figure 6 10 and make 5 element Yagi antenna complete below table by repeating item 1 21 Table 6 7 Characteristic of 5 Element Yagi Antenna Maximum Singha Level Hal Fowar seam vidin e c um m m omo Receiving Power Complete below table by synthesizing the experiment up to now Table 6 7 Characteristic of Yagi Antenna according to the number of Element Number of Element Maximum Single Leyal Vursus E p mie Am 79 EXERCI SE l Figure the driving principle of Yagi antenna by electron field Make clear the manufacturing way and electric characteristic of a radiators reflectors and indu
50. ation The adjustment is completed start Acquisition If the data acquisition is completed save the taken radial pattern in file Use the data box to confirma radial pattern exactly If set MSP Max Signal Position to 0 can see the radial pattern of this antenna Make the control plate to rotate 90 for the 500MHz Yagi antenna used for transmitting get a vertical polarization characteristic by loosing the screwon the polarization control plate 85 10 MM 12 L4 13 Figure 7 6 Setting of Vertical Polarization Transmitting Antenna Make a center of a spiral antenna used for receiving to be vertical with a rotary axis and set as Figure 7 7 to get a vertical polarization characteristic Click Antenna Initialize in Edit Menu of a software click the Auto button to data acquisition If the data acquisition is finished after select H Plane as Plane save the pattern in file Figure 7 7 Vertical Polarization Receiving Antenna Keep the 500MHz Yagi antenna used for transmitting to get a vertical polarization characteristic and set the spiral antenna used for receiving to get a vertical polarization characteristic Click Antenna Initialize in Edi t Menu of a software and click again Delete Screen then click the Auto button to data acquisition Observe three radial pattern Set a transmitting receiving antennas get a vertical polarization characteristic respectively The distance between antennas is r l 5m Make a
51. ce between Antenna Set as below in condition of main controller power off Power OFF 500MHz Oscillation Switch off 2 GHz Oscillation Switch off 10 6Hz Oscillation Switch off Modulation Switch Mod off After set the switch in main controller as below execute the Antenna Trainer program Power ON 500MHz Oscillation Switch on 6Hz Oscillation Switch off 10 GHz Oscillation Switch off Modulation Switch Mod on If a program window is executed execute the data acquisition in Pop Up Menu After select Antenna here select E Plane as Plane then control to be displayed 0 in antenna gain displayer by adjusting a signal attenuation The adjustment is completed start a data acquisition After the first experiment named the taken radial pattern to Antenna 1 and save it in a data box as E Plane To confirma radial pattern exactly use a data box Set MSP Max Signal Position to 0 can see a radial pattern of this antenna exactly 66 42 Make a polarization control plate to rotate 90 for the Yagi antenna used for transmitting get a vertical polarization characteristic Don t change a polarization direction of a full wave diamond loop antenna used for receiving Experiment again named to Antenna 2 and save this radial pattern in E Plane Figure 5 23 Vertical Polarization Transmitting Antenna 43 Set a full wave diamond loop antenna used for receiving to be got a vertical polarization characteristic as Figure 5 2
52. ctors Explain the relation between the number of element and gain of Yagi antenna Explain about the radial pattern of Yagi antenna What s the polarization characteristic of Yagi antenna 80 EXPERI MENT3 7 SPIRAL ANTENNA Let s measure a radial pattern for E Plane and I Plane of a spiral antenna in this experi ment We will study about a polarization characteristic of a spiral antenna Let s calculate a nalf power beam width of a spiral antenna by using antenna software BASIC STUDY l Spiral Antenna The spiral antenna having wide band is introduced by V H Rumsey in 1957 later J D Dyson gi ves proof experi mentally that the plane equiangular spiral and conical spiral antenna etc have an independent characteristic of frequency in 1959 Generally if the frequency of antenna is changed the physical size of antenna is changed Accordingly if the physical size of antenna is decided the ranged of using frequency can not help limiting But as a spiral antenna is what make an antenna armto rotate exponential functionally it can be used in wide band because can replace the change of physical size to the change of rotating angle And the characteristic impedance and radial pattern has a frequency independence not changed in wide frequency band and it has the characteristic of small size lightweight and non directivity Soit is used widely for theair communi cations radar system and receiving antenna of civilian satellite etc 1 1 Ge
53. data acquisition in Pop Up Menu to be executed Here after select Antenna select E Plane as Plane and control the signal attenuation to be displayed 0 in a displayer for an antenna gain The control is completed start the data acquisition Data acquisition is finished save the taken radial pattern in file To confirmthe radi al pattern exactly usea data box Set MAP Max Signal Position to 0 canseea radial pattern of this antenna exactly For the 500MHz Yagi antenna used for transmitting get a vertical polarization characteristic loose a fixing screw on a polarization control plate and make the control plate to rotate Figure 4 14 Setting of a Vertical Polarization Transmitting Antenna For the drooping antenna used for receiving get a vertical polarization characteristic set as Figure 4 15 50 12 Set Ine antenna al vertical posiben with roland axis Figure 4 15 Setting of a Vertical Polarization Receiving Antenna After click Antenna Initialize of Edit Menu of a software acquire a data by clicking the Auto button The data acquisitionis completed save the patterninfile after select H Plane as Plane 13 Keep a 500MHz Yagi antenna used for transmitting to get a vertical polarization 14 I3 10 characteristic and set a drooping antenna to get an even polarization characteristic In this time for the center of a transmtting antenna taken a vertical polarization characteristic and a receiving antenna get a
54. designed to radiate the electron wave from grounding plane toward helix axis and to have a radial pattern of pencil beamtype rotating toward coiled direction of a helix The herical antenna of this type has a merits which easy to match as the wide band and input impedance is about 1202 1402 as well as has a very efficient radial pattern T I AB OR SOL IO META E AM A Plane Geometry B Radial Model of Pencil beam Figure 8 1 Axial mode Herical Antenna The initial letter used to draw helix N Number of Rotation Over 3ti mes S Space of Rotation C tana pitch distance between the centers of a helix that is rising height when 1 rotate 1 10 1 2 X A Axial Length NS D Diameter of Helix d Diameter of Conductor Lead L Length of Rotation About aD 3 4 4 3 X pitch angle tan S C pitch angle of helix a The herical antenna becomes radiate an electron wave in axial mode when the circumference is 9 given about length of one wave The using frequency range of a herical antenna is given as formula 8 1 Waa C X 43 5 1 The sine wave travel from grounding plane toward opposite end point along helix Therefore the herical antenna is called a traveling wave antenna To understand the operating principle of a herical antenna consider one helix loop of A circumference as Figure 8 2 As the circumference of helix in optional moment tiis A the current is a positive value 4 in one plane of Loop and n
55. e Antenna Initialize in Edi t Menu of a software and click the auto button to data acquisition Data acquisition is completed save two drawn pattern in file 13 Keep the 500MHz Yagi antenna used for transmitting to get a vertical polarization characteristic and set the t 4 ground antenna used for receiving get an even polarization characteristic 4 14 1 Figure 3 13 Even and Vertical Antenna After click Antenna Initialize in Edit Menu of a software click Screen Delet and click the auto button for a data acquisition Observe three radial pattern Set again each transmitting receiving antennas to get an even polarization characteristic The distance between antennas is r l 5m Make the surrounding condition to same as the first experiment Take a E Plane radial pattern of aA 4 ground antenna and save in Dummy Plane Theoretically except an effect by power damage this radial pattern must same as the first radial pattern If the pattern is different so much have to do properly by finding the point where a reflection can be occurred After do properly continue the experi ment and save the new pattern in E Plane Click the data indicating line on upper View Menu of a data analysis program Two cursor Blue White used for E Plane and two cursor Yellow Green used for H Plane are appeared on the screen Click the arrow mark on bot side of color displayer the value in displayer will be changed by moving the cursor of s
56. e Ob EIE Figure5 14 Distance between Antenna Set as below in condition of power off Power OFF 500MHz Oscillation Switch off 2 GHz Oscillation Switch off 10 GHz Oscillation Switch off Modulation Switch Mod off After set a switch in main controller as below execute the Antenna Trainer program Power ON 500MHz Oscillation Switch on GHz Oscillation Switch off 10 GHz Oscillation Switch off Modulation Switch Mod on If the program wi ndow is executed execute a data acquisition in Pop Up Menu Select Antenna here and select E Plane as Plane then adjust to be displayed 0 in the gain displayer by adjusting a signal attenuation If the adjustment is completed start a data acquisition 60 11 12 After first experi ment save the taken radial pattern by making be this to antenna 1 in data box as E Plane To confirmthe radial pattern exactly use a data box Adjust MSP Max Signal Position to 0 can see exactly the radial pattern of this antenna Make a polarization control plate to rotate 90 to get a vertical polarization characteristic Don t change the polarizing direction of a circle loop antenna used for receiving Experiment again and make be Antenna 2 and save this radial pattern in a data Dox as E Plane Figure5 15 Vertical Polarization Transmitting Antenna Set the full wave circle loop antenna used for receiving to get a vertical polarization characteristic as Figure 5 16 Make th
57. e field strength of maximum radial direction to the required formula in the radial powr Pr pP P P x 13 13L W pM WE A Therefore substitute the value of current for the formula 1 2 and becomes Ty P go n Vim Same Size CA Infinitesimal Antenna B A 2 Dipole C A 2 Dipole Effective Wave Figure 1 9 The field strength at right angle direction with lead is proportioned to the area of oblique side It was explained already that the field strength maxi mum radial direction of infinitesimal is proportioned to the volume of current and length flowing into lead See Formula 1 2 The 14 volume I of current I A and length m is a size corresponding to the area S of oblique part as indicated in Figure 1 9 A Only the unit isn t m2 but m A If use this S the field strength of infinitesimal antenna becomes from the formula 1 4 bor E IR gt As the half wave dipole is the assembling of infinitesimal antenna rightly it will proportioned tothe area Sof oblique part inthe same Figure B But the size of flowing current isn t definite and the size of current is changed with sine wave in this case therefore it is difficult to indicate with the area S but if indicate the result becomes gaye ahs IS mA AL 2 m 07 1 6 and you can see that this area S becomes same size as a globular part in Figure C The length of lead direction of this globularity le is LE esu le P7 7 0 6
58. e indicate the position angle of cursor and the receiving power in that time as dB and the difference the angle between cursors with power display on below two presentation window Record in Table 1 2 the got value in this time Table 1 2 Power of Angle Receiving Power of E P ane For Angle Receiving Power of H Pl ane For Angle 18 Get the angle received the maximum power in E Plane pattern and the receiving power in that time Click the Maximum Single Level button on E Plane data window and confirm if it is corresponded the measured value and the got maxi mim value by moving the cursor And record on below Table 1 3 Table 1 3 Comparing E Plane and Theoretic Value The Value Using a cursor The Val ue by Maxi mum Recei vi ng Single Level Icon 21 Get the half angle of main beam power size in the E Plane pattern Click the Half Power Beamwidth button on the E Plane windowto confirmif it is corresponded the measuring val ue and got value using a cursor Keep in mind what the power is decreased is same as 3dB attenuation 101090 5z 3dB Calculate the anti power beamwidth in E Plane of a t 2 dipole antenna using below formula HPBW z 0 HPBWeft 0 HPBWRI GHT HP B W If the right and left of HPBW have a angle of 0 must add 360 to in the formula Repeat 18times the experiment procedure in the H Plane radial pattern HPBW z Click thedataindicatinglineinaviewmenuto delete all the cursors Compa
59. ed point becomes higher Figure 4 5 indicates tile angle of a ground element and the val ue of an impedance this becomes about 212 when becomes 90 and 50 2 in about 30 38 and becomes o 70 Q2 when go down just below 0 Figure 4 6 shows the setting of gamma matching system in a power feed part Make the impedance at a power feed point to match to the characteristic impedance of a coaxial cable by controlling the length of a gamma load place parallel with a vertical element and the variable condenser between the load and the central conductors of a coaxial cable Figure 4 7 shows the antenna taken a matching by placing a vertical radial in a coaxial antenna As connect a parallel radial d a distance between a central lead of a coaxial cable and a vertical element is taken by below formula TD a nt Vn om Za Impedance at a power feed point of drooping antenna Zo Characteristic Impedance of Coaxial Cable m hs in M iU m T We EN H I a a E y Figure 4 4 Vertical and Impedance Figure 4 5 Angle 9and Impedance of Vertical Element 46 Figure 4 6 Gamma Match Figured 7 Place the Vertical Radial in a Coax The experi ment set of an antenna contain a drooping monopole antenna in addition to a standard monopole The drooping monopole is very easy design method of monopole Figure 4 8 shows a drooping monopole exemplarily Figure 4 8 Drooping Monopole To explain the characteristic of a drooping antenna co
60. egative val ue in opposite val ue As showinfigure can connect point and point with arrowmark in same geometric direction and this makes to act alike dipole of one kind Int after short time thecurrent moves as short distancealong helix Nowthe di pol e becomes a shape rotated alittle That is this imaginary dipole becomes rotate identically with each frequency 02 of a transmitted wave type In Figure 8 2 the radial pattern toward both sides will be 0 The radiation of electron wave will be only toward axial direction of a helix I b Time X rg bY h Tine d Figure 8 2 One Loop of Herical Antenna If each loop forming helix is all folded and is same phase it is going to get a strong radi al pattern along both axis of helix as Figure 8 3 But Figure8 3isn taradial pattern of herical antenna in axial mode Since the phase difference is generated by occurring a propagation delay along helix for the radial pattern two lobes are not generated but one lobe toward axis The herieal antenna has similar radial pattern to the end fire antenna taking unique lobe toward endfire because the position of antenna array elements and the phase of feed current The coiled direction of helix decide a direction of circular polarization When set helix in side of grounding plane the coiling toward clockwise makes right circular polarization t0 generate and toward counterclock wise makes left circular polarization to generate Fi Figure 8 3 Rad
61. ene of Max Size rd Yo axs caused by Same Phase Radallon Aterualicn caused by Phase Difference toward diflerent diraztkn Same Distances A Diltarant Disarge REO i 3 Figure 10 4 Analysis of E Plane Far Field in Square Patch Figure 10 4 shows the picture drawing one slot by 3 dimensions In this figure axis and each o Oare used as a variable number of basic formula a and b in Formula 10 2 and 10 3 is a related value to the width a and length b of patch in Figure 10 4 The height hin Figure 10 4 is a value related to the thickness of base material of dielectric substance in Figure 10 1 and 10 2 The radial pattern of E Plane for two slots excited by same amplitude and phase is given as below formula Ah sin cos d F amal cos A cos 2 10 2 A cosg Where h is a height of slot same as the thickness of antenna base material D is a distance between two slots same as the length of patch antenna dX B Radiating Slot Figurel0 5 Type for Calculation of E H Plane Radial Pattern The H Plane pattern is given as below sinf cos e Pat aging 110 3 E Cos d 109 Where a is a length of slot Theoretically E Plane pattern and H Plane pattern have to be appeared as Figure 10 5 3 Input Impedance of Microstrip Antenna As the input impedance of 2 slot array antenna and 2 square patch antenna is a resistant element Reactance element 0 have a good radial characteristic The appr
62. er of main controller Power OFF 500MHz Oscillation Switch off 2 GHz Oscillation Switch off 10 GHz Oscillation Switch off Modulation Switch Mod off 7 After set a switch in main controller as below execute the Antenna Trainer program Power ON 500MHz Oscillation Switch off GHz Oscillation Switch off 10 GHz Oscillation Switch on Modulation Switch Mod on 8 The program wi ndow is executed execute Data Acquisition in Pop Up menu Here after select Antenna select E Plane as Plane and control to be displayed 0 in gain displayer hy adjusting the signal attenuation The adjustnlent is completed start Acquisition 9 f the data acquisition is completed save the taken radial pattern in file Use the data box to confirma radial pattern exactly If set MSP Max Signal Position to 0 can see the radial pattern of this antenna 10 Make the polarization control plate to rotate 90 for the 10GHz Horn antenna used for transmitting get a vertical polarization characteristic D Figure 8 8 Rotation of Vertical Polarization Transmitting Antenna 11 Fix to measure the axial mode radial characteristic of a Herical antenna 95 12 Click Antenna Initialize in Edit Menu of a software click the Auto button to data acquisition 13 Set again for the transmitting antenna get an even polarization characteristic and for receiving antennas get an axial mode radial characteristic The distance between antennas is r l 0m Ma
63. es the increasing of gain can be forecasted becomes restricted by feed damage This damage is occurred by coupling of inductance and capacity between numerous feed line In case of serial feed antenna the connection between patchs is linear accordingly the problem becomes few relati vel y This two type can be coupled by serial parallel array taken merit of two feed type As the numerous small serial arrays connect with parallel it is possible to make the feed circuit to be simple and to design large sized array antenna decreasing power damage 118 EXPERI MENT PROCEDURE Set a transmitting receiving antenna positioner and a computer which are main instrument of an antenna experimental set 2 Fix 106Hz Horn antenna on the polarization control plate in transmitter Set it to be even with earth to get an even polarization characteristic The transmitting Horn antenna as Figure 11 2 gets an even polarization characteristic Connect 106Hz oscillation output terminal in main controller and Cable connecting terminal of Horn antenna with SMA cable used for 2m Figure 11 2 An even polarization characteristic 3 Fix the 2 dimension array antenna on the polarization control plate in receiver to measure an axial mode radial characteristic Use the position control screw in receiver place the ground plane to be vertical with a rotary axis in receiver See Figure 1I 3 to set Figure 11 3 Setting of Even Polarization Receiving Antenna Connect t
64. f software click screen deletion on the editing menu again and gain the data putting Auto button Observe three radiation patterns Install again each receiving amp transmitting antenna in order to bear the character of 132 horizontal polarization Distance between antennas is rzl Om Identify the environment SU Tounding antenna with first experiment Get the E Plane radiation pattern of circle arranging antenna and save in the Dummy Plane Theoretically this radiation pattern must be equal with first pattern except effect by electric power loss If the pattern is quite different you must take proper measure finding place where radiation can occur After taking proper measure keep going experiment and save the new pattern in the E plane Click data indicating line on the view menu in the upper menu of data analysis program Two cursors for E plane sky blue white and two cursors for H plane yellow green represent on tile screen Click arrow being both sides to the displayer of each color and values of displayer will be changed moving same color cursor These indicate angle which cursor is located on and receiving electric power at that time in dt3 Also they indicate angle between cursors and difference of electric power in two displayers below Record val ues obtained at this time on the table 12 2 below Table 12 2 Receiving electric power by angle Recei vi ng Power of E Plane For Angle Recei vi ng Power of H Pl ane For
65. f the data acquisition is completed save the taken radial pattern in file Use the data box to confirma radial pattern exactly If set MSP Max Signal Position to 0 can see the radial pattern of this antenna 10 Make the control plate to rotate 90 for the Horn antenna is to be vertical with earth 120 Make the 2 di mension array antenna used for receiving to be vertical with a rotary axis and set as Figure 11 5 to get a vertical polarization characteristic In this time make the center point of front horn and the center of antenna used for receiving to bein straight i ne Click Antenna lnitializein Edi t Menu of asoftware click the Auto button to data acquisition If the data acquisitionis finished after select H Plane as Plane save the pattern in file Figure 11 5 Setting of 2 dimension array antenna Keep the Horn antenna used for transmitting to get a vertical polarization characteristic and set the 2 di mension array antenna used for receiving to get a vertical polarization characteristic In this time make transmitting and receiving antenna to be opposite position and Make the center of a front horn part of transmitting antenna and the center of receiving antenna to place in straight line Figure 11 6 Vertical and Ever Antenna Click Antenna Initialize in Edit Menu of software and click again Delete Screen then lick the Auto button to data acquisition Observe three radial pattern Set a transmitting receivi
66. ge of a spiral antenna 95 What s the polarization characteristic of a spiral antenna 89 EXPERI MENT3 8 HERI CAL ANTENNA Let s measure the radial pattern for E Plane and H Plane of a Herical antenna used for 106Hz in this experi ment We will study the polarization characteristic of a Herical antenna Let s calculate a half pawer beam width of a Herical antenna by using an antenna software BASIC STUDY l Circularly Polarized Wave The preceding experimented antennas is what have a linear polarization characteristic In the case of the straight wire antenna such as a dipole folded dipole and monopole the radiated field becomes same as a direction of physical wire For example in the case of a transmitting plane dipole the field is on plane and the magnetic field is on vertical plane This antenna is able to receive most largely the wave which the field is on plane Also the loop antenna has a linear polarization characteristic For example the vertical full wave loop antenna fed from floor does function like an even dipole radiates the wave type of even polarization Perhaps if feed not fromfloor but fromright or left side the radial wave type is to be vertical polarization The square waveguide transmit a linear polarized wave type In prior experiment of measurement for E Plane and H Plane you can confirm that must use all the same polarization If two transmitting receiving antenna is arranged tightly and control the steering direc
67. he 2 dimension array antenna and RF In terminal of a receiver with SMA cable used for m and connect OUT PUT 1KHz terminal of a receiver and Input 1KHZ in receiver of main Controller with BNC Cable used for Im 4 Measure the length of a 2 dimension array antenna and record in Table 11 1 119 Table 11 1 Length of Antenna and Feeder mm Length of Antenna 5 As Figure 11 3 the distance between antennas is isolated as rzl m Set the horn antenna used for transmitting and the single patch antenna used for receiving at to be even and opposite each other Make the center of a front part Horn Part of horn antenna and the center of a single patch antenna to place in straight line E Figure 11 4 Distance between Antennas r 6 Set as below in condition of turning off the power of main controller Power OFF 500MHz Oscillation Switch off 2 GHz Oscillation Switch off 10 GHz Oscillation Switch off Modulation Switch Mod off 7 After set a switch in mare controller as below execute the Antenna Trainer program Power ON 500Mttz Oscillation Switch off GHz Oscillation Switch off 10 GHz Oscillation Switch on Modulation Switch Mod on 8 The progranl window is executed execute ata Acquisition in Pop Up menu Here after select Antenna select Plane as Plane and control to be displayed 0 in gain displayer by adjusting the signal attenuation the adjustment is completed start Acquisition 9
68. he difference 5 What s the radial pattern of a Horn antenna 106 EXPERI MENT3 10 SI NGLE PATCH ANTENNA Let s measure a radial pattern for E Plane and H Plane of a single patch antenna in this experi ment We will study the radial characteristic of a single patch antenna Let s calculate a half wave beam width of a single patch antenna by using the antenna software BASIC STUDY l Characteristic of Square Patch Antenna ZR i m Ag FEED n Figure 10 1 Basic Square Microstrip Antenna Figure 10 1 shows the size of a basic square microstrip patch antenna The conductance of antenna i5 a function of width a and the resonance frequency is a function of length b The length b is given as below 50 494 0 4921 id 1 VE Where X is a wave in a dielectric substance A iS a Wave in a free space er is a relative dielectric constant of a base material Because the change of dielectric constant and feed inductance it is necessary to identify the exact length of patch when measure Figure 10 2 shows the current flowing into patch and the field around it The field is on the edge of patch connected with feeder mainly and is on opposite edge This field caused byaradial characteristic of antenna The wave radiated fromantenna get an even polarization characteristic as Figurel0 2 That is the even direction is E Plane x y plane and the vertical direction is H Plane y z plane The b spacing between two edge of a patch ante
69. he experi ment a values with given value in the antenna software If the calculated result is not accorded to this values experiment and calculate again Save the E Plane and H Plane data and output the result 115 EXCERCI SE Mean to feed to the microstrip patch antenna of 120 2 input impedance with a coaxial cable of Q characteristic impedance In this case design A 4 impdance inverter by 2 position 2 n Figure 10 1 decide a and b of a square microstrip patch antenna used for 2 4 GHz 3 Compare and explain the radial pattern of a microstrip patch antenna and a horn antenna 4 Take a gain of a single patch antenna 5 What s the polarization characteristic of a single patch antenna 116 EXPERI MENT3 11 2 DIMENSION ARRAY ANTENNA Let s measure the radial pattern for E Plane and H Plane of 2 dimension array antenna We wi study the polarization characteristic of a 2dimension array antenna Let s calculate a half power beam width of a 2 dimension array antenna BASIC STUDY l Microstrip Plane Array Antenna As the array element is a parameter giving an effect on radial pattern of an antenna of special array structure the entire radial pattern of given array antenna can be forecasted by the principle of pattern multiplication Where the pattern multiplication is means what multiply the radial pattern of individual antenna element by the array element As the square microstrip antenna and the 2 slot waveguide antenna is
70. hich place one reflector at rear of a radiator and place the entire element at front of a radiator as a director 1 Relation between Element Number and Gain Figure 6 3 shows the relation between the element number and gain and according to the gain wanted the element number is decided Figure 6 4 shows the relation between the length at axis direction of element arrangement Whole Length of Array and gain If becomes over 6 element the increasing of gain is decided by length at axis direction of array than element number To increase the gain to 2ti mes Increase 3dB can not help increasing about 2times the length at axis direction of array 71 E EE hay P HEIDE T Coote He Length 52 FEEFLLLLE bys HAHH Anntana 35 ATT L5 rH 1 1 i 23488T7TB31 1112 H1 HE THEO Element Number Yagi Element Number Figure 6 3 Relation between Figure 6 4 Relation between Length of Element Number and Gain Antenna and Element Number 2 Element Spacing Figure 6 1 shows each element spacing in the case of 2 8 element and over 9 element When make each element to the most proper length the change of gain is within 1 dB Element 2 O15 A D2 a 2 3 C1 oad Gib g 4 018 022 f OAT AMALIA gt B M1 ee Unt QIE O2 Qn t7 D ez Oe 220 POA Oe A H O16 02 Ole E U 18 25 Oe oz AAA 304 0404 3u 4 OI 023 O14 Oe O18 C25 a do 42 3 Length of Director When make No N0 2 in order fromthe most near ele
71. ial Pattern of Pencil Beam 3 Axial Ratio and Gain When receive the signal to be circular polarization the response of herical antenna has to maintain as identical size ideally though the field of receiving signal is rotated To explain this consider the case using the antenna to be circular polarization like dipole as a transmitting antenna and using the herical antenna as receiving antenna The polarization of transmitting signal will be changed by rotating dipole The ideal herical antenna must 92 get same receiving level for all direction of a dipole that is for all polarization But the radial characteristic of a herical antenna can be assymmetry a little because a helix has a limited size Accordingl y the receiving characteristic for the polarization of special direction can be appeared somewhat better than for other direction Here the response index of a polarization toward special direction for a polarization toward other direction is called the axial ratio of aherical antenna or the circularity This gives a definition with a ratio between amplitudes indicating max response and an amplitude of polarization indicating min response It can be said that the antenna respondi ng same for all polarization has axial ratio of 1 0 or 0dB The axial ratio is given as below pr TES AR EX d 2 where AR is an axial ratio N is a number of helix The axial ratio can be measured through a receiving and transmitting between antennas to be direct pol
72. ial pattern not to be 0 alike an infinitesimal antenna This infinitesimal loop antenna can be substituted for an infinitesimal antenna placed in zero point along z axis without change of a radial pattern But the input resistance of an infinitesimal loop antenna is very little value as below 122 Accordingly useitasareceivingantenna but it is difficulty to use for atransmitting antenna because of the radial resistance is too little Full Wave Loop Antenna l Theloop antenna full wave loop antenna of wave A is used efficiently for has a proper gain and input impedance is a value treating easy about 100 Q There are various type of a loop antenna That is a round shape square rectangle and diamond These all have a similar radial pattern and gain For the radial pattern of a full wave loop antenna it is important to suppose the current rangingalongtheloopline and to understand howget the electromagnetic field generated along it is added and offset 2 1 Current Distribution of Full Wave Loop Antenna 54 Let s think the circle Loop antenna of 1 zl of length on X Y plane The power feed point can be placed anywhere But the direction of power feed has an i mportant effect on a radi al pattern SUSSENT D xTRIBL TIGH LINC Fr 0039 X A Af FEED POINT e Figure 5 2 Current Distribution of Loop Antenna of Length 1X Let us suppose that the power feed point is on the bottom of Y axis and the loop spread along X axis
73. ide of a radiator as Figure 6 2 4 reat dresom A direction reflector yadiacor of ahead pes Esa Ere Q l Erad Eret i I Little nveraec PR Aid n sBrne longer phase thase Ihan Ave Sy tapeede 9C the chase more than Erad A La 7777 imc 8 retlec tion Ji a rat MR i E rod TN me 30 90 delay 2 E mihver yadam GO dicta 1 P rad j A 2 Element Yagi B Flow Chart about Operation of a Parasitic 70 Antenna attached Reflector Reflector See main text Figure 6 2 Operation of Parasitic Element In case of Reflector In this case what the phase is delayed 90 till an electron wave radiated fromradiator reach to the reflector and the phase of current lref flowing into reflector To be inducti ve reactance because of a length is little longer than A 2 is to be more delayed 90 than the radial field ina radiator And the electron wave reradiated fromreflector is to be delayed again 90 phase since the current flowing through a reflector delay 90 Though this is a very particular but to be as Figure B by indicating in vectorial That is the phase of an electron wave radiated from reflector Field Eref Status not radiated from reflector yet becomes finally moredelayed 270 than the electron wave Field Erad radiated fromradiator this means that Eref precede 90 the phase more than Erad During Eref process to ahead that i5 toward a radiator and reach the point of radiator also a phase is
74. imental set 2 Fix 106Hz Horn antenna on the polarization control plate in transmitter Set it to be even with earth to get an even polarization characteristic The transmitting Horn antenna set as Figure 9 3 gets an even polarization characteristic Connect 106Hz oscillation output terminal in main controller and Cable connecting terminal of Horn antenna with SMA cable used for 2m Figure 9 3 Setting of Even Polarization Horn Antenna 3 Fix the Horn antenna on the polarization control plate in receiver to get an even polarization characteristic at vertical position with earth Place the antenna in rotary center of receiver by using the position control plate See Figure 9 4 to set Figure 9 4 Even Polarization Receiving Antenna Connect the Horn antenna and RF In terminal of areceiver with SMA cable used for Im and connect OUT PUT 1KHz terminal of a receiver and Input 1KHZ in receiver of main controller with BNC Cable used for Im 102 4 0 Measure the length of a 106Hz Horn antenna in Figure 9 1 and record in Table 9 1 Table 9 1 Length of Antenna cm Ll Actual Antenna Length AS Figure 9 5 the distance between antennas is isolated as r lm Place the transmitting receiving antenna on opposite position of same height Figure 9 5 Distance between Antenna r Set as below in condition of turning off the power of main controller Power OFF 500MHz Oscillation Switch off 2 GHz Oscillation Switch off 10
75. in beam power in axial mode pattern by using two cursors Click the Half Power Beamwidth button on axial mode E Plane data window to confirm if same the measured value with button as taken value with cursors Table 8 3 Comparison of E Plane with Theoretic Value Taken Val ue Receiving Power With cursor Bgle 0 o Value by Maxi mum Receiving Power S Single Level Icom angle S Calculate a half power beam width of a herical antenna in axial mode E Plane with below formula HPEW g a p HPR Wen HPBWael 16 Repeat No 15 of the experiment procedure in H Plane radial pattern 96 HPBW 17 Delete all cursors by clicking the data indicating line in view menu Compare the experi mental values with given value in the antenna software If the calculated result is not accorded to this val ues experi ment and calculate again Save the E Plane and H Plane data and output the result 97 EXCERCI SE I Take the Axial ratio by substituting A D S Nin Table 8 1 to Formula 8 2 Take a gain by substituting A D S N in Table 8 1 tb Formula 8 3 What s the circular polarization Arrange the type of polarization and explain the difference between each polarization Explain the normal mode and axial mode of a herical antenna 98 EXPERI MENT3 9 EXP OF HORN ANTENNA Let s measure the radial pattern for E Plane and H Plane of Horn antenna used for 10GHz in this experiment We will study a r
76. indicated by dB ri and fr are distance between the first antenna and second antenna To decide a direction characteristic of an antenna numerically the concept of directivity 100 or direction gain is used generally The directivity is max radial intensity toward gi ven directionfor the averageradial intensity Theisotropicantenna radiating anidentical power toward all direction that is in ideal antenna the antenna gain direction gain equal to directivity 9 3 Measuring Gain of Antenna Of various method to measure a gain of antenna as the most thing is a method of reference antenna compare method or substitute method this is method comparing the receiving power of a reference antenna Pre and of a test antenna Press mutually The gain of a test antenna can be indicated by Formula 9 7 P Pal C Tage P Cr Ref 9 7 Indicate by dB becomes as below G rum P jean P ran G Reidh 9 0 Before use a substitution method must do calibration the reference antenna One thing of the method is what use two same antenna If the transmitting receiving power the gain can be calculated with Formula 9 9 day P gu Ga Ua 9 9 b Where G is gain r iS distance between antennas Po and Pre are transmitting receiving power respectively A is wave in free space same unit as r 101 EXPERI MENT PROCEDURE l Set a transmitting receiving antenna positioner and a computer which are main instrument of an antenna exper
77. itialize in Edit Menu of software and click again Delete Screen then click the Auto button to data acquisition Observe three radial pattern 16 5et a transmitting receiving antennas get a vertical polarization characteristic respectively The distance between antennas is r l 0m Make a surrounding condition of antenna to be same as the first experi ment Take the E Plane radial pattern of a horn antenna and save in Dummy Plane Theoretically if except an effect caused by a power damage this radial pattern has to be same as the first pattern If the pattern is different very much have to do suitably by finding the position where a reflection can be occurred After do suitably continue an experiment and save new pattern in E Plane Click Data Indicating Line in View Menu of upper menu of a data analysis program Two cursors Blue White used for E Plane and tow cursors Yellow Green used for H Plane are appeared on the screen f click an arrow on both si de of a displayer of each color the values in the displayer will be changed by moving the cursor of same color Theseindicate the angle of cursor position and the receiving power 104 in that time as dB show the difference of angle between cursors and power in below 2 displayer Record the values in below Table 9 2 Table 9 2 Receiving Power for Angle Recei vi ng Power of E Plane For Angle Recei vi ng Power of H Plane For Angle Use the cursor to take the receiving a
78. ization characteristic with a circle square and diamond full wave loop antenna respectively 69 EXPERI MENT3 6 YAGI ANTENNA Let s measure a radial pattern in E Plane and H Plane for Yagi antenna We will study the polarization characteristic of Yagi antenna Let s calculate a half power beam width of Yagi antenna BASIC STUDY 1 YAGI ANTENNA As the Yagi antenna is an antenna invented by Dr Yagi and Uda it is most representative antenna for endfire array It is in 1930 that this Yagi antenna is used for a wireless telephone of VHF mark Since generally the Yagi antenna has a simple structure and high quality function as a beamantenna it is used in place of VHF UHF mainly 1 1 Operation of Parasitic Element Figure 6 1 shows a 3 element Yagi antenna to be got a good characteristic and having a simple structure There are acentral element connected withatransmtter or receiver by feeder that is radiator and a reflecter and director leaving a space of 2 4 at the front and rear and these are the parasitic element which is not connected with transmitter Plast Flament S y Max Hadipe Crrection Hellaecto Rad arsr Director Reflector and Direetor are a Paruzitc Elemenla Figure 6 1 3 Element Yagi Antenna Let s know why does these parasitic element is operated asa reflector or director Let s give an example with operation of a reflector It is suppose that place little longer reflector than A 2 space out A 4 at left s
79. ke a Surrounding condition of antenna to be same as the first experiment Take the axial mode radial pattern of a herical antenna and save in Dummy Plane Theoretically if except an effect caused by a power damage this radial pattern has to be same as the first pattern If the pattern is different very much have to do suitably by finding the position where a reflection can be occurred After do suitably continue an experi ment and save new pattern in E Plane Click Data Indicating Line in View Menu of upper menu of a data analysis program Two cursors Blue White used for Axial Mode E Plane and tow cursors Yellow Green used for Normal Mode H Plane are appeared on the screen If click an arrow on both side of a displayer of each color the values in the displayer will be changed by moving the cursor of same color These indicate the angle of cursor position and the receiving power in that time as dB show the difference of angle between cursors and power in below 2 displayer Record the values in below Table 8 2 Table 8 2 Receiving Power for Angle Recei vi ng Power of E Plane For Angle Recei vi ng Power of H Pl ane For Angle 14 Use the cursor to take the receiving angle of max power in Axial Mode and the receiving power in that time Click the Maxi mumSingle Level button onthe axial mode E Plane window to confirmif a measured value is accorded to a taken value with cursor Record this in Table 8 3 15 Take a half angle of ma
80. l Set the main controller transmitting receiving antenna positioner and computer which are main instruments of the antenna experiment set 2 Set a height control bar on a transmitter and fix 500MHz Yagi antenna on the antenna fixi ng pack then set this on the polarization control plate In this time set this to be even With earth for an antenna get an even polarization characteristic The transmitting antenna set as Figure 6 8 get an even polarization characteristic Connect the 500MHz oscillation output terminal of main controller and the cable connecing terminal of Yagi antenna with SMA cable used for 2m LO OE G E 3 on Figure 6 8 Even Polarization Transmitting Antenna 3 Fix the 500MHz Yagi antenna to get an even polarization characteristic on the polarization control plate of areceiver Usethe position control plate of areceiver to place an antenna in rotating center of a receiver See Figure 6 4 to set Figure 6 9 Setting of Even Polarization Receiving Antenna Connect the Yagi antenna and RF In terminal of areceiver with SMA cable used for Im and connect OUT PUT 1KHz terminal of a receiver and Input 1KHZ in receiver of main controller with BNC Cable used for Im 4 Use below formula calculate the length of Yagi antenna and measure the actual length of antenna in 500MHz then record in Table 6 2 The exact oscillation frequency of RF signa generator is 500MHz ds 75 sale Figure 6 10 Yagi Antenna Table 6 2 Length
81. lane are appeared on the screen If click an arrow on both side of a displayer of each color the values in the displayer will be changed by moving the cursor of same color These indicate the angle of cursor position and the receiving power in that time as dB showthe difference 114 ine zl of angle between cursors and power in below 2 displayer Record the values in below Table 10 2 Table 10 2 Receiving Power for Angle Recei vi ng Power of E Plane For Angle Recei vi ng Power of H Pl ane For Angle Use the cursor to take the receiving angl e of max power in E Plane pattern and the receiving power in that time Click the Maxi mim Single Level button on the E Plane data window to confirmif a measured value is accorded to a taken value with cursor Record this in Table 10 3 Table 10 3 Comparison of E Plane with Theoric Value Taken Val ue With cursor Value by Maximum Receiving Power Single Level Icon Angle Take a half angle of main beam power in E Plane pattern by using two cursors Click the Half Power Beamwidth button on data window to confirm if accord the measured value with button as taken value with cursor Calculate a half power beam width of single patch antenna in E Plane HPBW O muenwen spun Repeat No 18 of the experi ment procedure in H Plane radial pattern HPBWi Fee Te el Delete all cursors by clicking the dataindicatinglineinviewmenu Compare t
82. late the antipower beam width of X 2 dipole antenna BASIC STUDY 1 RESONANCE OF LEAD Though very short lead if the high frequency current flow it makes a difference radia efficiency but the electromagnetic wave in proportion to the current strength The question is how make to flow the optimum current to a lead The current flow into a lead of high frequency open both end In the frequency f0 occurred a resonance phenomenon alike LCR direct current of B Pe e i QG J C yb E Ue 5 Curr E i i r I i T OO CPemmy lA BI 5 Dirad Resonanca Circuit Figure 1 1 Antenna and Resonance Circuit As Figure 1 1 A connect the high frequency galvanometer in the center of direct lead of suitable length L Set the frequency inlowand make to highit slowly the current begins to flowinto an antenna As make the frequency to be increased continuously the current of antenna increase gradually so like Figure it to be maxi mim at some frequency fo And make it higher and the current is to be decreased oppositely It can knowthat the relation between frequency and antenna current alike LCR direct resonance characteristic in Figure B Accordingly it can be shown that both end is opened and the lead to be center power feed resonant at frequency fo In this time the length of lead is about 1 2 of fo wave Why does the lead of length resonant with a high frequency has double wave length It can be thought as below As Fig
83. ll obj ect folder users want in setting screen or click the Finish button Figure 2 1 After some ti me belowscreen of file copying procedure is output If click Cancel in this ti me all install works are cancel ed Figure 2 2 f the message Please insert disk number2 is displayed on route install insert disk2 2 and click the OK button Figure 1 3 If the install is completed the below screen is displayed Select OK here all install work is completed Figure 2 4 After some time below folder is generated automatically If click the icon AT3000 Antenna Experiment System programis executed Clicktheicon AT3000 Antenna Experi ment Systemto delete the program Figure 2 5 If the install is completed the files related to execution and below the Low folder of 2type are generated in the folder appointed by user Default is Antenna and its details is as below Sample Sample Pattern mages Antenna Picture for each type AT3000 Folder which data to be saved when experi ment 2 EXECUTION 1 PROGRAM USED FOR ANALYSIS wee ane 2 PROGRAM USED FOR DATA ACQUISITION For the fine information see Experiment in Chapter 3 CHAPTER 3 BASIC STUDY amp EXPERI MENTS EXPERI MENT 3 1 HALF WAVE 4 2 DIPOLE ANTENNA Let s measure the radial pattern about E Plane and H Plane for 2dipole antenna used for 500MHz in this experiment We will study a polarization characteristic of dipole antenna Let s calcu
84. lue become difference Figure 2 3 shows the impedance change for a 2 2 dipole according to change the diameter d2 dl and spacing S of a parallel conductor As the ratio of didi and as spacing S is small the ratio of impedance change become large When you want to make this change ration to be large the 3lines folded dipole consisting of 3conductors is used as Figure 2 4 Also in this case the impedance change ratio is changed by the thickness and spacing of each lead complexly but Figure shows the simple case and when three all are same diameter the change ratio become 3 9 Also can increase the number of a parallel conductor If all conductor is same thick the change ratio can be calculated in N Number of Conductor The folded dipole has a impedance change property in compared with 2 2di pole except this it has the merit as below Driving Frequency Range is taken widely ii Though the non balanced class power feed lead as a coaxial cable directly the matching become easy etc Therefore it used for the radiator elements of Yagi antenna Since the radial resistance of radiator become lower value than 20Qin Yagi antenna if use the folded dipole which the impedance change ratio is 4 for a radiator the input impedance can be 70 80 2 S0 it become matching to the 3002 power feed if the impedance change ratio is 30 three line type with the coaxial cable of characteristic impedance 75 Q 25 ey msnm ur H1 Ape 1 3 2 P 14 dr s
85. ly the radial current placed in optional angle for earth since the radial length is 4 a radial field is decided by the current flowing into vertical element and the sum of a vector of a radial current This antenna has a similar characteristic to A 2 dipole antenna but the radiation of an electric wave can t be occurred almost to the direction of earth and the radiation is occurred in the area bounded by the central lead and ground lead Accordingly this is used mainly in a simultaneous call with the airplane taken off and landed in the control tower of airport The length of a central element is taken by follow formula Figure 4 2 _ t13 T a A MH 9 Also the length of radial is taken by follow formula since make the length of radial to be longer as 2 3 than a vertical element for the radial of an electric wave becomes maxi mum in vertical direction ENG hi LO Mme 9 45 Since the impedance at the power feed point of this drooping antenna is very low as 21 24 Q f feed directly with 50 75 Q of a coaxial cable SWR is to be worse So to go up the impedance at the power feed point of this antenna following method has been used Figure 4 3 shows the folding shape of a vertical element Since the impedance at the power feed point becomes 4times of it before fold can go up to 84 96 OQ l Figure 4 3 Fold the Vertical Element In figure 4 4 as incline the counter poise ground element to below the impedance at a power fe
86. main controller like below Power source on 500MHz launching switch off 2 GHz launching switch off 10 GHz launching switch on Modulating switch Mod on 0 After executing programwi ndow execute data gaininthe pop up menu After selecting antenna Je select E Plane and control in order to be indicated 0 on the antenna gain display window controlling signal attenuation After control is finished start data gain After data gain is over store obtained radiation pattern by file Use data box in order to ensure correctly radiation pattern Set MSP maxi mum signal place on 0 and you can find out radiation pattern of this antenna 131 10 let the polarization controlling plate circle 90 for horn antenna have vertical 11 10 polarization character Figure 12 12 Installation of circle arranging antenna Install like figure 12 12 for circle arranging antenna for receiving have vertica polarization character Click antenna initialization on the editing menu of software and gain the data putting Auto Dutton After finishing data gain select H Plane and save the pattern in a file Keep the horn antenna for transmitting in order to bear the character of vertical polarization and install the circle arranging antenna for receiving in order to bear the character of horizontal polarization to face each other FIGURE 12 13 Vertical Horizontal Antenna Click antenna initialization on the editing menu o
87. maxi mim value on center isn t ID but lol 2 This sine wave current become go down 0 at both end of leadl and become maximum in center of a dipole lead2 by increasing again at a dipole lead2 Add the distribution of two current flowing into the lead 1 and lead 2 of a folded dipole it IS same as a current distribution of a dipole antenna Accordingly the radial current is also same Also the input impedance of a folded dipole can be taken with below formula Ip 2 Po Zol b Pe 4 Ze b Zed where Pp Zp Ipis a power impedance of dipole and current and Pp Zp Ipis a impedance of a folded dipole and current respectively Consequently you can see that the input impedance of a fold dipole become larger than a dipole input impedance of 739 4 2 40 452 4 73 2 2922 S 2 3 When it is same the input power as a thickness of a conductor in Figure2 2 CAD C as the current of 1 2 folded dipole is half of a 2 2di pole the input impedance become 73 Qx 2 13 x 25300 Q When the thickness is different in Figure 2 2 B it is characterized that many current flow into a lead of thick side In this time l l the ratio divided before and after is changed variously according to the thickness and spacing S of a conductor When the conductor in side of non power feed is thick become an impedance over 4 ti mes as largeasaA 2dipole It characterizelikethis that the radial characteristic of a A 2folded dipole is same as a 2 dipole but the impedance va
88. ment after read this book before use it 2 Please check if connect AT3200A Main Controller to Motor Control Cable of AT3200C Receiver before turn on 3 Avoldoperationor storage of the instrument within 3mexisted the reflector fromthe antenna of transmitter and receiver 4 Make the antenna to run using the main controller or PC surel y 5 Don t make to stop by physical power when the antenna of receiver runs 0 The input voltage of AC is 220V exclusive use 7 Avoid storage of the instrument in humid area 3 ATTACHMENTS Please check if there are belowattachments When open this pack after purchase the instrument 1 AT3200A Main Controller Main Controller PC Connecting Cable 2m Motor Control Cable Im User s Manual 2 AT3200B Transmit Unit Body 1 3 AT3200C Receive Unit Body l 4 AT3200D Antennas See Table 1 1 1 1 L L L L3 4 NAME OF EACH PARTS 1 MAIN CONTROLLER Belowfigureis a Main Controller This is dividedintoareceiver and transmitter At first the left receiver consists of Signal Level Window displaying the revolving angle power Switch BNC Type jack Switch controlling the revolving direction CW CCW and Step Controlling Switch Figure 1 2 Main Controller POWER SWITCH Main Power On Off SWITCH SIGNAL INTENSITY DISPLAYER 50dB 10dB REVOLVING ANGLE DISPLAYER 0 360 500MHz 26Hz 106Hz OSCILLATION ON OFF SWITCH amp LED MODULATION SWITCH MODULATION
89. ment froma radiator if the di ameter of element in Figure 6 5 can take the most suitable length of each director HW UPHLELLILITITTTTITTTTTT CETIUTEEHICILIITILEFTFLT SOA eee Teh Element of Diameter a ASM LX a A150 rele AP MUD Length of Elcueat 0 440 F wave B La m 35 7 ASO gt A 1234567 8391011121314 15151718 152621 Director Number Figure 6 5 Method taking each Director The length of a radiator has not relation almost to the characteristic of an antenna and the length of reflector is not important so much in over 4 element Therefore set to the said length in 3 element then have only to adjust later on 12 Yagi antenna or Yagi Uda antenna is named for Prof H Yagi and Lab S Uda experimenting the parasitic array in Japan 1920 This antenna is designed by the idea that since each antenna has own current distribution if superpose each antenna the multi antenna can be constructed The radial pattern of this multi antenna is a result fromthe addition and difference of an electron wave radiated from currents distributed to each antenna Ina folded dipole antenna the radial pattern for the special directionis increased by being added each other the current distributionof 21lead near by each other Also between the current distribution of a loop antenna that is between the currents distributed at each point of aloopantenna at a distance of same distance making the proper radial pattern by bei ng
90. n Figure 3 5 A 4 Ground Antenna on Complete Ground Antenna n monopole antenna 4 ground antenna it is like that the current flowinto a pole of one side Also the input voltage is half of a dipole Accordingly the input impedance of a monopole becomes half of the input impedance of a di pole Zint A monopole 3682 Since the current is same as 2dipole the radial power may be same But the beam width becomes half of dipole because there are the ground face Accordingly the directivity and gain become 2times of a dipole 3 3 1 momepele 2x l164 3 2 or MiB The radial pattern of a l 4 monopole on the ground face is same type as the radial pattern of a A 2 dipole over zero angle The theoretical radial pattern is given in Formula 3 3 and it is same shape as a half wave di pol e 1 cos 5 coss PO Vi amane 9 sin d 0820 If the monopole put on the ground face as the height d 2 as Figure 3 6 the monopole antenna drive as if two antennas is arranged The electric waves radiated from upper part and lower part antennas becomes different with each height on the ground face 37 MONOPOLE RECEIVED SIGNAL dra af Fi Fu MAGE Figure 3 6 Radial Coupling by Monopole and Image Monopole This is to generate an Array factor Figure 3 6 shows the coupling shape of the electron wave radiated from monopole and i mage monopole this is similar what couple the radial electri wave by a dipole on a complete conductor X 4 Ground
91. n even polarization characteristic is to be in Strait line see Figure 4 16 to set Figure 4 16 Vertical and Even Antenna Click Antenna Initialize in Edit Menu of a software and click Delete Screen in Edit Menu again then acquire a data by clicking the Auto button Observe three radial pattern Set again each transmtting receiving antennato get a vertical polarization characteristic The distance between antennas is rzl 5m Make a surrounding condition to same as the first experiment Take a E Plane radial pattern of a drooping antenna and save in Dummy Plane Theoretically except an effect caused by a power damage this radial pattern must same as the first pattern f the pattern is differ very much have to do suitably by finding a point where a reflection can be occurred After do suitably continue the experi ment and save a new pattern in E plane Click the data indicating line in the Edit Menu of upper menu of a data analysis program Two cursors Blue White used for E Plane and two cursors Yellow Green used for H Plane are appeared Click thearrow mark at both side of a color displayer the value in a displayer by moving the cursor of same color These display the position angle of cursor and the receiving power as dB The difference of an angle between cursors froma power on below t wo displayer Record the values in below Table 4 2 51 Table 4 2 Receiving Power for Angle Recei vi ng Power of E Plane For Angle Recei vi ng
92. n this ti me set an antenna in parallel with earth to get an even polarizaticed characteristic The transmitting antenna set as Figure 3 8 has an eve polarization characteristic Figure 3 8 Setting of Even Polarization Antenna Set the frequency selecting switch to OFF and connect the 500MHz oscillated output terminal and Yagi antenna with a SMA cable J Fix the A 4 ground antenna to get an even polarization characteristic on the polarization control plate of receiver Set an antenna in center of rotating axis console receiver by using the moving control plate of receiver Set by refering Figure3 9 Connect the A 4 ground antenna and the RF IN terminal of receiver with a SMA Cable used for im and also connect the OUT PUT 1KHz of receiver and the input 1KHz terminal of main receiver with a BNC Cable used for Im Figure 3 9 Setting of Even Polarization Receiving Antenna 4 Calculatethelength of 4 4 ground by using belowformula and measure the length of an actual antenna then record in Table 3 1 39 So Table 3 1 Length of XN 4 Ground Antenna cm 5 Make the distance between antenna as r l 5mto isolated adjust the center of a transmitting antenna and receiving antenna in parallel See Figure 3 10 to set Figure 3 10 Distance between Antennas 6 Set in condition of the power of main controller as below Power OFF 500MHz osciUation switch off 2 GHz oscillation switch off 10 GHz oscillation switch off Modulation
93. nding to it is the starting point Array factor between W n 2 and VUz sis the maximum This is identical with maximumvalue in the polar coordinate 2 SINGLE CIRCLE ARRANGI NG Generally linear arranging antenna i5 easy array of element and making of feeder But in the H Plane and E Plane in order to design identically type of beam the number of element al ways must be multiplied doublefor oneline because of this it has afault that area required becomes greater Circle arranging antenna which antenna structure is symmetrical on the angle can realize hi gh benefit antenna as arranging many antenna on the small area Moreover circle arranging antenna by non linear arranging has a merit which can get aradiation pattern of Taylor water supply type Like figure 12 3 field of circle arranging antenna which isotropic element with N quantity on the x y plane as the same space is located along the circle with radius a is given HR Ey 8 d E athl ij a 126 FIGURE 12 3 N Circle Arranging Structure Rn is the distance from the n th element to the observing point At the observing point field is given as the following formula RF E A kotiu Pama g t au b Pe 12 6 In amplitude of current excited to the n th element On angle of n th element on the x y plane an phase of current excited to the z th element IL e di ZI m pg vrM o a eee TENE F indicates isotropic element if it 1 aSsumed tha
94. ner of a drooping antenna What s the shape of a radial pattern for a drooping antenna The impedance and radial pattern according to a gradient angle of four lead placed on each corner of a drooping antenna Take an impedance and radial pattern in case of the gradient angle of four lead is 30 45 60 90 What is the radial characteristic with a drooping antenna 53 EXPERI MENT3 5 FULL WAVE LOOP ANTENNA In this experiment let s measure a radial pattern for a E Plane and H Plane of a full wave oop antenna We will study apolarizationcharacteristicof afull waveloopantenna Let s calculate a half power beam width of a full wave loop antenna by using an antenna software BASIC STUDY i 2 Infinitesimal Loop Antenna The infinitesimal loop antenna which is smaller size than 8 t or 8 1 has dual relation to ainfinitesimal dipole antenna it is used for a special application such as direction searching Here the duality theory is a theory settling the substitutional relation formed between a radial by power resources infinitesimal dipole and a radial by magnetic current resources infinitesi mal loop Figure 5 1 Current in Infinitesimal Loop Antenna Since a loop length of an infinitesimal loop antenna is very shorter than wave in al part can regard the current as an amplitude and phase etc as Figure 5 1 Accordingly the field to direction of Z axis becomes O zero For all direction except Z axis the rad
95. ng antennas get a vertical polarization characteristic respectively The distance between antennas is rzl 0m Make a surrounding condition of antenna to be same as the first experiment Take the E Plane radial pattern of 2 dimension 121 array antenna and save in Dummy Plane Theoretically if except an effect caused by a power damage this radial pattern has to be same as the first pattern If the pattern is different very much have to do suitably by finding the position where a reflection can be occurred After do suitably continue an experiment and save new pattern in E Plane Click Data Indicating Line in View Menu of upper menu of a data analysis program Two Cursors Blue White used for E Plane and tow cursors Yellow Green used for H Plane are appeared on the screen If click an arrow on both side of a displayer of each color the values in the displayer will be changed by moving the cursor of same color These indicate the angle of cursor position and the receiving power in that time as dB show the difference of angle between cursors and power in below 2 displayer Record the values in below Table 11 2 Table 1 1 2 Receiving Power for Angle Recei vi ng Power of E Plane For Angle Recei vi ng Power of H Plane For Angle 17 Use the cursor to take the receiving angle of max power in E Plane pattern and the recei vi ng power in that time Click the Maxi mim Single Level button on the E Plane data window to confirmif a meas
96. ngle of max power in E Plane pattern and the receiving power in that time Click the Maxi mim Single Level button on the E Plane data window to confirmif a measured value is accorded to a taken value with cursor Record this in Table 9 3 Table 9 3 Comparison of E Plane with Theoretic Value Taken Value With cursor Value by Maximum Receiving Power Single Level Icon Angle Take a half angle of main beam power in E Plane pattern by using two cursors Click the Half Power Beamwidth button on data window to confirm if accord the measured value with button as taken value with cursor Calculate a half power beam width of horn antenna in E Plane with below formula HPBWg ugpwen HPBen 7 Repeat No 18 of the experiment procedure in H Plane radial pattern HPBWi Delete all cursors by clicking the data indicating line in view menu Compare the experi mental values with given value in the antenna software If the calculated result is not accorded to this values experiment and calculate again Save the E Plane and H Plane data and output the result 105 EXCERCI SE When make the isolated distance of antenna to be 2times in Figure 9 4 how dB is decreased 2 Explain the effect caused by the opening angle of a pyramidal horn antenna 3 Explain what s the shape similar to the radial pattern of a pyramidal horn antenna 4 Take the gain of antenna with numerical formula and experiment and explain t
97. nna is about length 0 49 Ad of half wave in the dielectric substance Thisisareason that the opposite slot becomes an antenna exciting to the inverse phase But the field radiating to two parallel slot becomes add to same phase in direction of broadside that is direction of y of antenna 107 H FLANE ELEC TAC CURRENT ELECTRIC l FELD 4 _ ELECTRIC UwWw FIELD N N Xv w UN Figure 10 2 Current Distribution and Main Type of Field 2 Radial Pattern in case of two slots is distributed One analogy to calculate the characteristic of square patch antenna simply and clearly is what compare the patch antenna in Figure 10 1 with the waveguide slot antenna taking 2 sl ot in Figure 10 3 Since the 2 slot waveguide slot antenna in Figure 10 3 is equal to the patch antenna in Figure 10 3 two radial pattern is appeared identically To understand the radial pattern of 2 slot waveguide antenna pay attention to what select distancebfor thefieldradiated fromboth slot becomes same phase as Figure 10 4 The distance between each slot becomes same at any point on y axis Figure 10 3 Two Parallel Slot in Wavegui de Therefore the field caused by two slot becomes radiate maxi mally since to be added by becoming same phase In other direction it is not added completely as same phase for the distance between two slots is different Accordingly the radial pattern will be get a main lobe maxi mum size at direction of y axis 108 L
98. nsider a half wave di pol ehavi ng i mpedance of 73Q as Figure 4 9 If each leads consisting the half of below part is divided to 180 as Figure 4 9 c it becomes a A 4 ground antenna taking the characteristic impedance of 37 Q But as Figure 4 9 b if consist of each leads stretching for 90 45 froma right angle it becomes a drooping antenna getting a characteristic impedance of almost 502 This is matched exactly up to the characteristic impedance of a coaxial cable AM Aid ia GMTIME O MAA GROUND PLANE L A B C Figure 4 9 A Italf Wave Dipole B Drooping Antenna C A 4 Ground Antenna EXPERI MENT PROCEDURE SETTING OF EXPERI MENTAL NSTRUMENT l Set a transmitting receiving antenna positioner and a computer which are main instrument of an antenna experi mental set 2 Set a height controller on a transmitter and fix the 500MHz Yagi antenna on a fixing pack of an antenna then set on the polarization control plate Set this at a parallel position with earth for the antenna get a parallel polarization characteristic The transmitting antenna set as Figure 4 10 has a parallel polarization characteristic Figure 4 10 Setting of a Parallel Polarization Transmitting Antenna Set OFF the selection switch and modulation switch in a transmitting of main controller connect a 500MHz oscillation output terminal and Yagi antenna with SMA used for 2m 3 Attach the stationary bar onareceiver And fix the drooping
99. nsmitting lead and antenna connecting point 26 2 Fera aed i SWR FT E eas ae 2 4 where Pris the power transmitted through a impedance nonumi form point Pri ls the power reflected at a impedance nonuniform poi nt SWR is a sine wave ration SWR Zi Zi If complete matching since Zi Zi SWR Zan Z 1 the sine wave isn t occurred In this case the reflected power isn t Peo Sarat dil O5 Accordingly all the power is transmitted When power feed into transmitting lead in 4times half wave folded dipole 73 Qof a lead impedance 4x732292 Q the sine wave generated The sine wave ratio in this time become SWR Zer 2 124 ee 2 6 i op ar LRL 1 310 Pr 1 Prl SMe 1 l 4 004 Gets In this time 64 of power is transmitted 36 1s reflected This result isn t the worst state But it isn t advisable also Accordingly it is desirable that do an i mpedance matching bet ween the transmitting lead and antenna as Figure 2 7 MFEDAN CCL TRANSMITTER MATCHING ah 7 ACCEA A TS Akt Figure 2 7 Impedance Matching between the Transmitting lead and Antenna 3 Half Wave Folded Dipole The antenna experiment set contains a 0 5 GHz half wave folded dipole antenna As former case The dipole of this type has a 292 Q input impedance The transmitting lead given to connect to 0 5GHz antenna is a 502 coaxial cable It is presented 2ways to connect a 502 coaxial cable and a 2922 folded dipole antenna One is without Balun and an
100. ntrol plate Place an antenna on rotation center of areceiver using the position control plate See Figure 2 11 to set HL M m TM ms Foot Figure 2 11 Setting of Even Polarization Receiving Antenna Connect the folded dipole antenna used for receiving and the RF IN terminal in receiver with a SMA Cable used for Im and connect the OUT PUT 1KHz terminal in receiver and the INPUT 1KHz terminal in a main controller with a BNC Cable 4 Calculate a folded dipole in 500MHz using below formula and measure an actual length of antenna Then record in Table 2 1 The exact oscillation frequency of a RF signal generator is 500MHz 29 i dear i d ae Table 2 1 The Length of Folded Dipole Antenna era 5 Make the spacing between antennas to be isolated as r l 5mas Figure 2 12 and set to be parallel the center part of Yagi antenna and folded dipole antenna r Figure 2 12 Distance between Antennas r 6 On condition that the power OFF of main controller execute an antenn software after setting as below Power OFF 500MHz Oscillation Switch off 2 GHz Oscillation Switch off 10 GHz Oscillation Switch off Modulation Switch Mod off 7 Turn on the main controller power and set the oscillation switch and modulatiox switch as below Power ON 500MHz Oscillation Switch on 2 GHz Oscillation Switch off 10 GHz Oscillation Switch off Modulation Switch Mod on 8 Execute a AT3200 Antenna Experiment systemprogr
101. of Yagi Antenna cm Achual Antenna Length 5 AS Figure 6 11 the distance between antennas transmitting is isolated as rel receiving antennas to place in a straight line each other 5m Make a center of each F Figure 6 11 Distance between Antennas r 0 Set as below in condition of turning off the power of main controller Power OFF 500MHz Oscillation Switch off 2 GHz Oscillation Switch off 10 GHz Oscillation Switch off Modulation Switch Mod off After set a switch in main controller as below execute the Antenna Trainer program Power ON K 500MHz Oscillation Switch on 2 GHz Oscillation Switch off 10 GHz Oscillation Switch off Modulation Switch Mod on 8 The program window is executed execute Data Acquisition in Pop Up menu Here after select Antenna select E Plane as Plane and control to be displayed 0 in gain displayer by adjusting thessignal attenuation The adjustment is completed start Acquisition If the data acquisition is completed save the taken radial pattern in file Use the data box to confirma radial pattern exactly If set MSP Max Signal Position to 0 the radial pattern of this antenna d j Can see 76 10 Ll 15 ilie Make the control plate to rotate 90 for the 500MHz Yagi antenna used for transmitting get a vertical polarization characteristic by loosing the screw on the polarization control plate Figure 6 12 Setting of Vertical
102. olarization Transmitting Antenna 62 Connect the cable connecting terminal of afull wave square loop antenna to a REIN termi nal of receiver with SMA cable used for Im and connect a OUT PUT 1KHz terminal of receiver to Input 1KHz terminal of a main controller with BNC cable used for Im Use below formula to calculate the length of a full wave square loop and to measure the length of an actual antenna in 500MHz then record in Table 5 2 E Lm Talbe 5 2 Length of Full Wave Square Loop Antenna cm The distance between antennas is isolated as rzl 5m as Figure 5 18 Set center of each transmitting receiving antenna in a straight line of same height Figure 5 18 Distance between Antenna Set as below in condition of main controller power off Power OFF 500MHz Oscillation Switch off 2 GHz Oscillation Switch off 10 GHz Oscillation Switch off Modulation Switch Mod off After set a switch in main controller as below execute the Antenna Trainer program Power ON 500MHz Oscillation Switch on 2 GHz Oscillation Switch off 10 GHz Oscillation Switch off Modulation Switch Mod on If the programwindowis executed execute a data acquisition in Pop Up menu Select Antenna here and select E Plane as Plane then control to be displayed 0 in an antenna gain displayer by adjusting a signal attenuation If the adjustment is completed start the data acquisition After the first experiment named the
103. om antenna software If the calculated result differ fromthese values repeat an experiment and calculation when difference over T Save the data of E Plane and H Plane and output this result Until nowexperimented with a folded dipole antenna using the impedance conversion bal un of 4 1 Tofindadifferenceof an antenna with 4 1i mpedance conversion bal un and without it experi ment based on the experi ment procedure from No 1 through No 21 And compare the data in this ti me without 4 1 impedance conversion balun with the data with it and record 23 EXCERCI SE l Explain why there is a difference between the impedance of afolded di pole and a A 2 di pol e Explain some difference between when to be impedance matching and when to be impedance mat chi ng Explain how change of a gain directivity and antenna efficient etc when feed directly to a folded dipole with 75 Qcoaxial cable and when feed with 4 1 bal un 4 Explain the impedance change caused by the distance d of a folded dipole antenna 5 What s the polarization characteristic of a folded dipole antenna 34 EXPERI MENT 3 3 A 4 GROUND ANTENNA Let s experiment a radial pattern of E Plane and H Plane for the X 4 folded antenna used for 500MHz in this experiment Let s see a polarization characteristic of a A 4 folded antenna Calculate a half power beam width of a 4 folded antenna BASIC STUDY After an existence of a electric wave is proved by Herz in 188
104. ometrical Structure of Spiral Antenna As the spiral antenna of all frequency independent antenna there are Conical Spiral Log Periodic Antenna and Equiangular Spiral Antenna etc The equiangular spiral antenna has a characteristic that the distance from a starting point to optional point is increased exponential functionally for spin angle and also has a structure that the armrotate as 180 and expand For this antenna the radiation IS occurred strongly if the traveling wave in arm becomes same phase in lead element nearby andthe radiation is not occurred by attenuating if becomes an inverse phase Figure 7 1 2Arm Equi angular Spiral Antenna The geometrical structure of a spiral antenna is taken by below formula 81 e ra exp 7 7 1 Oa 1 exp 7 2 py ro exp 7 3 pane 7 4 where a Spiral Constant r0 Radius in Antenna Feed pl Distance from starting point of P arm to outside wire p2 Distance from starting point of P armto inside wire P3 Distance from starting point of Q armto outside wire 04 Distance from starting point of Qarmto inside wire o Spin Angle from starting point 6 Rotary Angle ais Spiral Constant deciding the expansion of antenna If the value a is little the expanding speed becomes lower and if the valuea is large the expanding speed becomes faster Accordingly if the value ais to belarge the armbecomes little relatively and the value ais little the length of arm becomes longer r decide max
105. or caused by becoming openlittle by little The fonnula indicated by dB is as below G can 10 084 10 log al eu wells Lgs mar a a4 The values of L E dB and L H dB can be taken if calculate s and t at first with formula 9 1 and 9 2 9 2 Electric Wave Damage in Free Space The power received by antenna decrease according to far away from transmitting antenna In free space the receiving signal power is in inverse proportion to the square of distance between a transmitting antenna and receiving antenna The power damage caused by an isolated distance between antennas is called the electric wave damage L F If show the electric wave damage on the free space by mathematic formula becomes 42 L rim I log we 2 log fpes where r is a distance between antennas Ais an electric wave period in a free space same unit as r For given wave formula 9 5 shows that L is changed by only distance between antennas This relational expression can be taken experimentally as measure the receiving power from antennas placed in other distance with transmitted signal from some antenna However must maintain the direction between two antennas during experi ment since the antennas have a directivity generally If can knowthe isolated di stance between antennas can calculate the power attenuation between receiving power in optional distance and in other distance The numerical formula indicating this is _ Fy A gH a log 0 6 where A is a damage
106. other is with a balun used for 4 1 impedance change 3 1 Connecting without a Balun Figure 2 8 shows the configuration connecting a 50 Gcoaxial cable a 3002 parallel round lead and some 300 Ohalf wave folded antenna without a Balun The relation between the transmitted power PT and the reflected power Pre is D SHR tU ye i HT WRIT M 0 8 2j Mona dy HALF wA E FOLSE gt NIP E ee LAHI L Hi WE AIN Figure 2 8 Folded Dipole Without Balun If the impedance is matched completely the power of 100 is transmitted But some 50 is transmitted in this time the remained half will be reflected The lost 3dB is what has a damage of 3dB in compared with a complete impedance 3 2 Connection using a Balun of 4 1 impedance change HAD A GNG PR 30032 Hal z wax FOLSED DPC E ou DOAIA DAR F Figure 2 9 Folded Dipole with Balun Figure 2 9 shows the connection of a 50Qcoaxial cable and a 300 Q half wave folded dipole with a Balun of 4 1i mpedance change It s better that connect the 72 Qcoaxial cable as RG 59U to a parts assembled the folded dipole and balun But in this case connect with 50 Qcoaxi al cable the 4 1 change isn t desirable change When match 50 and 300 2 needed 6 1i mpedance change desirably But despite of theincomplete matching it is sufficient to an improving effect with only 4 1 impedance chage Since the 4 1 impedance converter let the 300 Qimpedance change to 75 Gi mpedance the im
107. oximate value of an input resistance i5 as below Glid _ BOA Nt Eg a est TS 16 Kin jj T 2 10 4 Where a is a length of slot A iS a wave in free space H PLANE E PLANE Figure 10 6 Theoretic E H Plane Radial Pattern for two slots excited to Same Phase with Same Size b Ad 2 where Xd Theoretically as the input impedance of patch is about 1202 the impedance of a microstrip line and input unit of coaxial cable must be 120 Q But to connect with the 50 Qcoaxial cable using in experiment set for antenna the 502 microstrip line is used To match the impedance between 502 microstrip line and 1202 patch use the A 4 impedance inverter as Figure 10 7 The A 4 impedance inverter is a useful technique for the impedance matching in narrow band The characteristic impedance Z of A 4 impedance inverter to match Zi and Z is as below L y 2125 110 5 NT Figure 10 7 A 4 of Impedance Z for matching impedance Zi Z Zi is an impedance of a coaxial cable or microstrip line taking 50 if Z is an impedance of a patch antenna the characteristic impedance of XA 4 impedance inverter connected to patch and microstrip is as below Zi Y Z Za v 50I 789 0 63 110 Figure 10 8 shows the sigle patch antenna in antenna set and A 4 impedance inverter of 18 Q E z b zb cM PATCH IMPETDIARTL ISE TB DJLuHIE3 WAVE OTE FOR IMPEDPnaMCE PAT CESS Xx IM EDANCE EEG t ADAPT TC THE COAXIAL GABLE P
108. pedance change with a 50 Qcoaxial cable make a sine wave of 75 50 1 5 to be occurred In this case The relation between a transmitting power and a reflected power is as below J Pr l F EE 1 0 04 0 96 Accordingly all the power of 100 isn t transmitted and it is transmitted Only 96 and reflected only 4 The power transmtting effect of half wave folded dipole with balun become better as good as 2times than a folded dipole without it This lead a result of difference as almost 3Db when measure EXPERI MENT PROCEDURE SETTING OF EXPERI MENT APPLIANCE l Set the transmitting receiving antenna positioner which is a main appliance of experi ment set and computer 2 Set the height control bar on a transmitter and fix a 500MHz Yagi antenna on antenna fixing 28 pack and then set an antenna on a polarization control plate In this ti me set an antenna to get an even polarization characteristic evenly wit ground The receiving antenna setting as Figure 2 10 has an even polarization characteristic Figure 2 10 Setting of Even Polarization Transmitting Antenna 0n condition that a power OFF of main controller set the frequency select switch in transmitter in OFF and connect a 500MHz oscillation output terminal and a Yagi antenna with SMA Cable 3 Connect the stationary bar to a receiver and fix the folded dipole antenna used the 4 1 impedance conversion balun to get an even polarization characteristic at a polarization co
109. r and fix 500MHz Yagi antenna on an antenna fixing pack then set these on a polarization control plate Set an antenna at vertical position for earth to get an even polarization characteristic The transmitting antenna set as Figure 5 11 get an even polarization characteristic Connect 500MHz oscillation output terminal of main controller and the cable connecting terminal of Yagi antenna with SMA cable used for 2m Figure 5 11 Even Polarization Transmitting Antenna 3 Fix the full wave circle loop antenna on the polarization control plate of receiver to get an even polarization characteristic Place an antenna to rotating center of receiver by usi ng a position control plate of receiver See Figure 5 12 to set Figure 5 12 Setting of Even Polarization Receiving Antenna Connect a cable connecting terminal of a full wave circle Loop antenna and a RF IN terminal of receiver with MA cable used for Im and the OUTPUT IKHz terminal of receiver and a Input 1KHz terminal of receiver in main controller with BNC cable used for Im 3 Calculate the length of a full wave circle loop in 500MHz with below formula and measure an actual length of antenna and record in Table 5 1 59 Figure 5 13 Full Wave Circle Loop Antenna Table 5 1 Length of Full Wave Circle cm The length between antennas is isolated as rzl 5m as Figure 5 14 Make a center of each transmitting receiving antennas to place in a straight line of same height oe e
110. r transmitting and the single patch antenna used fox receiving at even position with earth Make the center of a front part Horn Part of horn antenna and the center of a single patch antenna to place in straight line Figure 10 11 Distance between Antennas r 6 Set as below in condition of turning off the power of main controller Power OFF 500MHz Oscillation Switch off 2 GHz Oscillation Switch off 10 GHz Oscillation Switch off Modulation Switch Mod off 7 After set a switch in main controller as below execute the Antenna Trainer program Power ON 500MHz Oscillation Switch off 2 GHz Oscillation Switch off 10 GHz Oscillation Switch on Modulation Switch Mod on 8 The program window is executed execute Data Acquisition in Pop Up menu Here after select Antenna select E Plane as Plane and control to be displayed 0 in gain displayer by adjusting the signal attenuation The adjustment is completed start Acquisition 9 f the data acquisition is completed save the taken radial pattern in file Use the data box to confirma radial pattern exactly If set MSP Max Signal Position to 0 can see the radial pattern of this antenna 10 Make the control plate to rotate 90 for the Horn antenna is to be vertical with earth 113 11 Make the single patch antenna used for receiving to be vertical with a rotary axis and set as Figure 10 12 to get a vertical polarization characteristic In this time make the center
111. re 2 1 The Folded Dipole antenna can be made by connecting two parallel dipole antenna with a fine lead Also the antenna folding a conductor as the length is A 2 and of fine and long shape is named a A 2 folded dipole or half wave folded antenna For aA 2 folded dipole antenna when make a conductor spacing S to be narrow in proportion to awave anda thickness of a conductor is same both conductor size is Same and flowa current of same phase as Figure 2 2 4 Since the sum of current flowing into two conductor is same as a current of a A 2 dipole fed by an same input power as Figure 2 2 C the field strength and directivity characteristic of arA 2 folded dipoleis same as aA 2 dipole But an impedance is different with A 2 dipole That s why thei mpedanceis inverseproportioned to 2mul ti plication of power feed poi nt current in case of an antenna of same input power in PzR I RzP I L3 Currenl ci iR Aiz Dipole p Figure 2 2 Current Distribution of a 4 2 folded dipole and dipole For the half wave dipole in Figure 2 2 C the current is 0 at both end of dipole and it is a sine wave to be maxi mum value ID at center Accordingly the current distribution of dipole can be indicated as below Kz Ipsin 5 4 lal 24 Here Z is a coordinates axis for the direction of antenna length and Lis a length of antenna In Figure 2 2 A the half wave folded dipole has a current distribution of sine wave at dipole lead 1 Only The
112. re the experi ment values with the given value in the antenna software If the calculated result isn t corresponded to this values experiment and calculate again When there are difference more T Save the data of E Plane and H Plane and output the results After pull a cell of dipole antenna of some 5ram experiment again from No 1 through No 22 based on above experiment procedure Since the object of this experiment is the frequency change in accordance with the change of antenna length the receiving power for a 500MHz frequency will be some changed So record about the difference by comparing with former results after experiment former in order once again 22 EXCERCI SE 1 What S role of an antenna in telecommunication 2 What s the isotropic source Also what s this usage 3 What s the radial pattern Explain the difference between the transmitting and receiving pattern of an antenna 4 Explain about a dipole antenna 5 How to divide the radial characteristic of an antenna What s the radial pattern of a dipole antenna 23 EXPERI MENT 3 2 FOLDED DIPOLE ANTENNA Let s measure the radial pattern about E Plane and H Plane for a folded dipole antenna in this experi ment We will study the radial characteristic of afolded dipole antenna Let s calculate the anti power beam width of a folded dipole antenna using an antenna software BASIC STUDY 1 Folded Dipole 3 E A t Figure 2 1 A 2 Folded Dipole As Figu
113. rence dB between max value and cursor s position Use two cursors to take a half angle of a main beam power in E Plane pattern of Antenna data box Use below formula to calculate a half wave beam width in E Plane of a full wave circle loop antenna HPBWi Omnes o P xpauvignt Repeat 14th experiment procedure in a radial pattern of the third data box HPBW Close anoption of cursor Thewindowreturn to theinitial screen Compare the experi mental values with a given values by antenna software If a calculated values is not accorded to this values experiment and calculate again Ref The position of a hal wave beam width take with antenna software though it stray fromright 3ri B point To observe the cursor s position selected by software open the cursor option then select a pattern you want Select the Options Set Cursors at 3dB item The cursor will be placed automatically Use this itemto take fast the approximate value of a half power beam width in the next experiment If you necessary can adjust the to be high accuracy Save the data of antenna 3 and output the result Must shows a radial pattern of two data box Full Wave Square Loop Antenna Fix a fulle wave square loop antenna on a pojarizat on control plate of receiver to be got an even polarization characteristic Use a position control plate of receiver to place the antenna in rotating center of receiver See Figure 5 17 to set Figure 5 17 Even P
114. ribution and Directivity of A 4 Vertical Ground Antenna Accordingly the field strength of earth is half of A 2 dipole radial field strength flowing the same size current into center current anti node of lead Also power feed point i mpedance becomes half of a center feed A 2 dipole and the resistance becomes about 362 Since the cubic directivity take on earth only in the A 4 vertical antenna it becomes shape like what cut a doughnuts circularly to half and lay face down the section as Figure 3 2 Figure 3 3 indicates a directivity of vertical side and afield strength on earth when change length of a conductor The strength of field in Figure 1s a value within a radial power of ikmand distance of mle about 1 6km When the length of conductor is 5 4 82 0 6025 the field strength on earth becomes maximum and indicate about 1 4ti mes of the distance is 0 25 A a i i REN i 2 a ao B B Tee oes 240 260 260 mw m Figure 3 3 Length Height of Vertical Antenna and Vertical Side Pattern Since a gain of a folded antenna standardize a vertical A 4 antenna it become about ti mes 3dB of a 5 X 8 vertical antenna If longer than 5 4 8 the sub lobe of an obtuse angle becomes large and the field strength go down The power feed impedance of a vertical ground antenna becomes half of a dipole antenna becomes different for the thickness of conductor as well as nor ground antenna Figure 3 4 indicates the impedance change for
115. rization 3l 14 I3 10 Ls characteristic and make the folded dipole antenna used for receiving to get an even polarization characteristic In this time set the Yagi antenna taken a vertical polarization characteristic and the folded dipole antenna taken an even polarization characteristic in parallel fitting its center by referring Figure 2 15 After click Antenna Initialize in Edit Menu of software click Screen Delete in Edit Menu of a software then click the Auto button for a data acquisition Observe three radial pattern Especially take note of the third experi mental result Set again for each receiving transmitting antennas get an even polarization characteristic The distance between antennas is rzl 5m Set the environmental condition to same as the first experiment Take E Plane radial pattern of a folded dipole antenna and save in Dummy Plane Figure 2 15 Even and Vertical Antenna Theoretically this radial pattern must same as the first pattern except an effect caused Dy a power damage If the pattern differ so much must do properly by finding the position where a reflection can be occurred After do suitably experiment continuously and save a new pattern in E plane Click Data Indication Line in upper Edit Menu of a data analysis program On the screen 2 cursors used for E Plane Blue White and 2 cursors used for H Plane Yellow Green is appeared Click the cursor by both side of color displayer the values
116. rrent distribution become different according to a point of power feed As an example Figure B and Figure E is all high frequency antenna of length A but the current direction and voltage polarity onleadis todiffer and theradiation characteristic especially the directivity is to differ entirely because of the position of power feed point is different 3 HALF WAVE DIPOLE As this antenna is a useful one of the simplest structure it is called a half wave doublet or dipole simply The doublet or dipole means a electric dipole and in case of a voltage distribution in Figurel 6 means what the left and right of lead become a constant and nonoscillatory charge according to the polarity of power The standard of half wave dipole is what does center feed in Figure 1 7 AJ This is called a center fed dipole In the case of the thickness of lead is very slim in comparison with wave the current distribution becomes sine wave as the dotted line in Figure 1 7 A It can see an assembling of a infinitesimal antenna Therefore the radial field strength of half wave dipole can be calculated with an assembling of infinitesimal antenna and for the maxi mum strength of right angle direction with Lead when the current of power feed point is I A it becomes E IB Em Vi 1 2 Ris isolated distance km from antenna The directional characteristic of half wave dipole is almost similar to the infinitesimal antenna it becomes a shape 8 and shape of cubic
117. rs Blue White used for E Plane and tow cursors Yellow Green used for H Plane are appeared on the screen If click an arrow on both side of a displayer of each color the values in the displayer will be changed by moving the cursor of same color These indicate the angle of cursor position and the receiving power in that time as dB showthe difference of angle between cursors and power in below 2 displayer Record the values in below Table 6 3 Table 6 3 Receiving Power for Angle Recei vi ng Power of E Pl ane for Angle Receiving Power of H Pl ane for Angle 17 Use the cursor to take the receiving angle of max power in E Plane pattern and the receiving power in that time Click the Maximum Single Level button on the E Plane data window to confirmif a measured value is accorded to a taken value with cursor Record this in Table 0 3 Table 6 4 Comparison of E Plane with Theoretic Value Taken Val ue Receiving Power With cursor Aande Value by Maxi mum Single Icom f f 18 Take a half angle of main beam power in E Plane pattern by using a cursor Click the Half Power Beamwidth button on data window to confirm if same the measured value with button as taken value with cursor Calculate a half power beam width of Yagi antenna in E Plane with below formula BPBW HPGe B sensi 19 Repeat No 18 of the experiment procedure in H Plane radial pattern PEW 20 Delete all cursors by clicking the dataindic
118. sa reliability As it is manufactured by etching the copper panel becomes the least of all the problem on manufacturing such as open or short circuit But the array antenna using a patch antenna has very narrow band of using frequency so it can be used only in band given exactly The microstrip array antenna of parallel feed type is what feed with parallel to give suitable phase to each element But to make main beamat vertical position with plane of arrayed antenna 117 generally feeding with same phase Figure 11 1 Microstrip Patch Array To make the phase of current feeding to each element must array the transmitting line and antenna elements to be symmetry The structure like tree called cooperate feed is used generally to transmit the power with same phase But it can be occurred the problemon designed space when there are many elements f use numerous matching element called A 4 inverter can match exactly all radial elements to 50 feeding to antenna as Figure 11 1 It is possible to connect the array element with serial It may be efficient well but the seri al feed type is complex to design in compared with parallel feed type caused by the dependent relation between each element The element of each patch antenna is had to be seen equi val ent value to 2 slot antenna and had to be considered the mutual coupling effect between patchs for calculation In the case of parallel feed array antenna if increase the number of element to 2 ti m
119. sappeared little by little Because of the parasitic inductor far away fromthe driving antenna element and the induced current organized to a parasitic inductor becomes decreased So the degree contributing to the antenna gain is to be weak little by little This relation is given in Figure 6 7 and Table 6 2 13 12 11 10 Gain dB SW on Eh J nm ce 12343567 8 5 1011 Number ot sheets H Figure 6 7 Relation between the Number of all element of Yagi Antenna and Gain Table 6 2 Gain of Yagi Antenna according to the Number of Array Element Spacing 1 5 A The input impedance of Yagi antenna is a function of input impedance of a radiator but it is affected very much froma parasitic elements It is easy to take that the theoretical input impedance for a3 element dipolealTay is about 2552 The change of ainput impedance accordi ng to the antenna structure is large comparatively and the values from 2052 to 10052 are often used Like know as above discuss Yagi antenna is one type on antenna structure not speci al antenna model Actually there are various transforulation of Yagi antenna Since the easy method to analysis the Yagi antenna the analysis and ol timize for this antenna do always with computer calculation and simulation Fortunately many experi mental and numerical studi es have been doing the results are recorded in the thesis text book and technical book erc 74 EXPERI MENT PROCEDURE Setting of Experiment Instrument
120. save two pattern to file 13 Keep the 500MHz Yagi antenna used for transmitting to get a vertical polarization characteristic and set A 2 dipole antenna used for receiving to get a even polarization characteristic as Figure 1 17 14 Click the delete screen in a edit menu of programand after click the antenna initial state click the Auto button for a data acquisition 15 Observe three radial pattern Are you expect the third experiment result Explain 20 Even Polarlzation Vertical Polarization Transmitting Antenna Transmitting Antenna p Figure 1 17 Setting of Transmitting and Receving Antenna 16 Set again each transmitting receiving antenna to get a vertical polarization characteristic The distance between antennas is rzl 5m Keep the surroundings of antenna with the first experiment Get E Plane radial pattern of A 2 dipole antenna and save in the Dummy Plane Theoretically this radial pattern must same as the first pattern if except the properly by finding the point which can be generated a reflection After do properly experiment continuously and save a new pattern in E pl ane 17 Click the data indicate line in the view menu at a upper menu of a data analysis program Two cursor used for E Plane Blue White and two cursor used for H Plane Yellow Green are appeared Click the arrowat side of presentation wi ndowfor each color the same color cursor is moved and the value of a presentation window will be changed Thes
121. sed for 10 GHz What s the polarization characteristic of a 2 dimension array antenna 124 EXPERI MENT3 12 CIRCLE ARRANGI NG ANTENNA Let s measure radiation pattern about E Plane and H Plane of circle arranging antenna this experiment We ll study polarization characteristic of circle arranging antenna Using software let s calculate half power beam width of circle arranging antenna BASIC STUDY l Array Factor Let s consider thecasethat each element is arranged linearly liked equally as seen figurel2 1 for examine calculating method of arranging factor of antenna In case of receiving far electron magnetic field on the transversal plane 9 0 distance between signaler and each element i5 essentially identified Thus current supplied to elements is added exactly the same phase usi 4 Figure 12 1 4 Element Linear Array Figurel2 1 when 9 gt 0 according to moving right element into left element each element is far fromsignaler as d sin Othan fore element This reason makes phase of current supplied to each element different Phase difference W is given by Y fdam 8 12 1 Array factor AF for linear arranging made up of N piece element is written _ ther Sini V2 o AF e sin CP 2 ES In above formula phase factor e indicates phase difference between the phase center and the starting point Omitting this phase factor it is given by r a SIDA TIZ AF Av sin PID 273 When W 0 AN is the maximum value it
122. surrounding condition of antenna to be same as the first experi ment Take the E Plane radial pattern of a spiral antenna and save in Dummy Pl ane Theoretically if except an effect caused by a power damage this radial pattern has to be same as the first pattern If the pattern is different very much have to do suitably by finding the position where a reflection can be occurred After do suitably continue an experi ment and save new pattern in E Plane 86 Click Data Indicating Line in View Menu of upper menu of a data analysis program Two cursors Blue White used for E Plane and towcursors Yellow Green used for H Plane are appeared on the screen If click an arrow on both side of a displayer of each color the values in the displayer will be changed by moving the cursor of same color These indicate the angle of cursor positionand thereceiving power in that ti meas dB showthe difference of angle between cursors and power in below2 displayer Record the values in below Table 7 1 Table 7 1 Receiving Power for Angle 10 Recei vi ng Power of E Plane For Angle Recei vi ng Power of H Plane For Angle Use the cursor totake the receiving angle of max power in E Plane pattern and the receiving power in that time Click the Maxi mim Single Level button on the E Plane data window to confirmif a measured value is accorded to a taken val ue with cursor Record this in Table l 2 Table7 2 Comparison of E Plane and Theoretic Value
123. switch Mod off 7 Turn on the power of main controller and set the oscillation switch and modulation switch as below then execute the Antenna Trainer program Power ON 500MHz oscillation switch on 2 GHz oscillation switch off 10 GHz oscillation switch off Modulation switch Mod on 8 Open the window of data acquisition in Antenna Trainer program and select an antenna And select E Plane as Plane and adjust to be displayed 0 on gain displayer by adjusting the quantity of signal attenuation This adjust is completed start the data acquisition 9 The data acquisition is completed save get radial pattern in file To confirm the radia pattern exactly use the data box Set the MSP Max Signal Position to 0 radial pattern Can see exact 40 10 Set the 500MHz Yagi antenna used for receiving to get an vertical polarization characteristic in parallel with earth by rotating the polarization control plate as 90 as 3 11 Figure 3 11 Setting of Vertical Polarization Transmitting Antenna 11 Set the A 4 ground antenna used for receiving in vertical with earth to get a vertical polarization characteristic as Figure 3 12 and set in center of rotating axis by moving the position control plate And in this time set the center of receiving antenna and the ground plate of a monopole antenna in a straight line Figure 3 12 Setting of Vertical Polarization Receiving Antenna 12 Keep the pattern drawn in E Plan and click th
124. t accorded with this values experiment and calculate again Save the data of E Plane and H Plane and output the result 43 EXCERCISE 1 Why does the length of ground antenna becomes half of a dipole 2 How over large size is the ground face of a ground antenna 3 What s the input impedance of a A 4 ground antenna 4 Describe the radial pattern of a A 4 ground antenna 5 What s the polarization characteristic of a 4 ground antenna 44 EXPERI MENT 3 4 DROOPING ANTENNA In this experiment let s the radial pattern of E Plane and H Plane for a drooping antenna used for 500MHz We will study the polarization characteristic of a drooping antenna Let s calculate the half power beam width of a drooping antenna by using an antenna software BASIC STUDY 1 Drooping Antenna There is an element of 1 4 length vertically froma central lead of a coaxial cable as Figure 4 1 Also as this is the antenna attached a ground lead of A 4 length radially in sheath conductor thelead has an optional angle with earth this is the antenna attached the counter poise ground lead of a kind instead of a ground of A 4 ground antenna L v ee Elemact fi Figure 4 1 Ground Plane Figure 4 2 Vertical Element La For there is this counter poise ground lead this is prevented a current from leaking from a sheath conductor of a coaxial cable to external and there is no unnecessary radiation of an electric wave in cable Assemble vectorial
125. t a level with ground to get a even polarized characteristic The transmitting antenna set as Figure 1 12 has even polarized characteristic E AE Ue Rh Figure 1 12 Setting of Even Polarized Transmitting Antenna Set OFF the oscillation switch for frequency ina transmitter of a main controller and connect the 500MHz oscillation output terminal and a Yagi antenna with a SMA Cable used for 2m 3 After set an antenna stationary bar to a transmitter fix a dipole antenna to a polarization control plate attached on a stationary bar And set an antenna at right angle with ground to get a even polarization characteristic and control the antenna to take place in center of a rotating axis of receiver using two control pin See Figure 1 13 to set Figurel 13 Setting of a Even Polarization Receiving Antenna Connect a dipole antenna and RF IN terminal of receiver with a SMA cable used for Im and connect a OUT PUT 1KHz terminal of receiver anda Input 1KHz in receiver of main controller with a BNC Cable 4 Calculate the length of X 2dipole in 500MHz and measure a length of actual antenna by using below formula and record in Table 1 1 The exact oscillation frequency of RF signal generator is 500MHz 17 Table 1 1 The Length of X 2 Antenna cm Note The antennalength has to be decided by considering the ratio betweenalength of conductor and di ameter end effect load effect in the end of lead and i mpedance discontinuity In this case
126. t dimension and phase of current power feeding to each element of the single circle arranging antenna wi th 2V quantity is equal array factor can be written as follows AF RN iEeeyindoosts 3 3 8 e FL 12 7 To make power feed by micro strip line the same phase micro strip arranging antenna element must be an even number Because feeder structure can be symmetrical In case of single circle arranging radiation pattern is wi del y affected by the element number of antenna and distance to the center point FIGURE 12 4 Radiation Pattern Change of Circle Arranging Antenna According to the Isolated Distance Change Y z plane 127 28 5 o Be 10 FIGURE 12 5 Radiation Pattern Change According to the Circle Arranging Element Number Change y z plane 3 MEASUREMENT Measurement equipment and systemused inorder to measure characteristics of thecirclearranging antenna i5 like figure 12 1 and 12 6 vec Hatank Analyzer ET Bas Iri qgnrgnna 5 Tg Hle C2 gam horn Puedes antenna a NO Abszrber FIGURE 12 6 Antenna Measuring System TABLE 12 1 Measuring Equi pment Equi pment Spectrum anal yzer AT6060D Frequency sphere power anal yzi ng Standard gain horn DGB 520 Standard gain providing To measure radiation pattern and gain of circle arranging antenna the standard horn antenna having 8 4 12 6 GHz frequency band and the Anechoic chamber etc is used And using network analyzer measure the
127. tage becomes maximum in the center and minimum in both ends Also voltage is opposite to current maximum in both end and minimum in the center volage Tha slamiig wave on sine Wave If taken Figure 1 3 Voltage Current Distribution on both end open A 2 lead Since the standing wave was occurred a standing wave on lead the size of voltage and current is to set according to position As a on board antenna is a means to flow high frequency current into a lead makes this standing wave to be occurred on lead Figure 1 3 shows that one standing wave is occurred in the lead of 2 length In Figurel 1 if the frequency of power make to be 2times 3times of resonance frequency fo How it will 11 become As for fo The 2 lead is to be for 2fo and to be 3 2 for 3fo anything become integral multi A 2 Figure 1 4 shows voltage and current distribution on lead The resonance frequency of LCR direct current but On experiment it isn t one In the specific multi frequency the resonance can be occurred In the case of lead in some integral multi frequency the resonance is occurred for the lower resonance frequency fy Here fois named a basic frequency of lead or inherent frequency and 2f 3fo 1s named harmonics resonance frequency The case of using the lead of antenna by resonating with high frequency is named high frequency excitation n fehl About Ju M Aboul 3f T inherent Frrequency
128. the length of antenna has to be shorter than X 2 5 As Figure 1 14 the distance between antennas is isolated as rzl 5m Control the transmitting receiving antenna to opposite each other Figure 1 14 Distance between Antennas r 6 Set the oscillation switch and modulation switch for frequency in state of the power is turned off as below Power OFF 500MHz Oscillation Switch off 2 GHz Oscillation Switch off 10 GHz Oscillation Switch off Modulation Switch Mod off 71 Turn the power of main controller on and set a oscillation switch and modulation switch for frequency as below Power ON 500MHz Oscillation Switch on 6Hz Oscillation Switch off 106Hz Oscillation Switch off Modulation Switch Mod on 8 After set as above execute a experi ment appliance programfor antenna Execute the exe file named Windows AT3200 antenna experiment system Then below window is generated Here click the data acquisition in pop up menu and set the data acquisition window 18 If below window is set select a antenna type And do initial state after execute a delete screen in edit menu Then select E Plane as Plane and control to be displayed 0 on antenna gain displayer by controlling signal attenuation If the control is completed click the AUTO Dutton to start a data acquisition oy a oe Xx i j DL 1 i H L FM LHTNM IH o HEB 2 5 i IN reda esc h ae da eye A SUM 9 Finish a data acquisition save a got radial pattern
129. tion to get same polarization characteristic becomes accept well the signal But if one antenna of two rotate 90 becomes receive a weak signal for the cross polarization isolation Theoretically since the cross polarization isolationislarge unlimited y any signal must not be received But actual cross polarization isolation is not to be unlimited There are an elliptically polarized wave and circular polarization in kind of a pohuization of an antenna The elliptically polarized wave is generated by the collate of two field vector regards two vectors as different towlinear polarization each other Two vectors are placed vertically each other have same frequency and travel toward same direction But their amplitude and phase have a different value respectively If the amplitude of two vectors is same respectively and have a phase difference of 90 exactly becomes a circular polarization If the amplitude of one vector or other vector is 0 becomes a linear polarization It can regards that the linear polarization and circular polarization is the special case of an elliptically polarized wave To bea circular polarization must make the field to rotate rapidly according to travel the wave There can be many ways to generate the circular polarization One thing is what radiate together an even polarization wave having the phase difference of 90 with a vertical polarization wave This is similar to draw Lissajous pattern of perfect circle as input a
130. ure 1 2 the high frequency current travel along lead to vertical direction A by the high frequency e t to be power feed at lead O point This is called a traveling wave the traveling speed is same as electric wave spread through space The current arriving a lead terminal point Ais reflected by ooi mpendence completely and return to power along lead This 10 IS a reflected wave Therefore the traveling wave and reflected wave transmitted from power continuously are existed on the lead Now set a frequency of power in a resonance frequency the traveling wave and reflected wave are to reciprocated on a one lead like O A or O A as below If the polarity of power is inversed fitted when the reflected wave return to power the traveling power and flected wave on lead become stronger The relation between a length of lead and resonance frequency fo in this ti me become 150 ayaa Lm Hzlacued Wave SN aln M NC UR Cement a E Aes Es Terling waye Ex Age m me zi Traveling Wasa nn de Lagin tanst tad be M A ee HMetezted Wey Figure 1 2 The reason that the electric wave of wave 3 resonate to lead A 2 c a I mm T 2 The Excitation of Antenna If the lead is to resonate the traveling wave and reflected wave of same size is occurred on the lead and the voltage and current on lead become as Figure 1 3 with occurring a interference each other by these Figure shows the size of each voltage and current and the vol
131. ured value is accorded to a taken val ue with cursor Record this in Table 11 3 Table 11 3 Comparison of E Plane with Theoretic Value Taken Val ue With cursor Value by Maximum Receiving Power Single Level Icon Angle 18 Take a half angle of main beam power in E Plane pattern by using two cursors Click the Half Power Beamwidth button on data window to confirm if accord the measured value with button as taken value with cursor Calculate a half power beam width of 2 dimension array antenna in E Plane HPBWg upawen O HPBen 7 19 Repeat No 18 of the experiment procedure in H Plane radial pattern HPBWi 20 Delete all cursors by clickingthedataindicatinglineinviewmenu Compare the experi menta values with given value in the antenna software If the calculated result is not accorded to this values experiment and calculate again 122 21 Save the E Plane and H Plane data and output the result 123 EXCERCI SE i Means to array four microstrip patch antenna of 1202 input impedance and to feed with a coaxial cable of 5 OQ characteristic impedance In this case design A 4 impedance inverter by 3 position Draw 2 dimension lay out m case of arraying 16 microstrip patch antenna used for 10 GHz Compare and explain the radial pattern of single microstnp antenna and 2 di menstion array antenna Take a gain of a microstrip antenna arraying by 2 dimension the 8 mcrostfip patch antenna u

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