(O)RLANS IN THE FREQUENCY BAND 2400 – 2483.5 MHz Dublin
Contents
1. 57 Page 1 DO QO Electronic Communications Committee ECC within the European Conference of Postal and Telecommunications Administrations CEPT O RLANS IN THE FREQUENCY BAND 2400 2483 5 MHz Dublin September 2004 57 Page 2 INDEX TABLE 1 PURPOSE OFTHE REPORT nrrainn i AA A E A svtecosiesesedes 3 2 INTRODUCTION AS RE LE dosere sson esor 3 3 REGULATORY ENVIRONMENT AND TECHNICAL 3 3 1 TISERS MANU THE RE Re 4 3 2 LECHNICAT PARAMETERS dese dean nn et dock just Saeed LA RER LA CRIE SE 5 4 MARKET INFORMATION ce ann tn mn a ae re nn SEEDS OTISO ds uses 6 4 1 PEEACING ON THE MARKET a 6 42 MARKET AND TENDENCY das ri rene basa no rat tte cadet te 6 4 3 RATIONALE FOR POTENTIAL MISUSE cccssssssssscccceecececccccessssssnseececeeeeccececesseeeeseaeaaaaaaeceesesseseeeesessaaaaeeeeeeeeeeeeeeees 7 5 DEPICTION OF POTENTIAL CHALLENGE uuu cccccccssscccccesssscccessssscccesssscccecesssccccesescccesensesccccessssscccessssesccesssee 7 6 COUNTRIES EXPERIENCE ne na late TaS 8 7 CONSEQUENCES Se ccitivixsceseticssitvsaxscecnseccoatcewencenenseleceescndessecnsebecaes cedetensnsvaneveviecessecnschaneesentessdetesensesectesvasesveetecsesesess 10 8 CONCLUSIONS si nn ste Re EE rt ein rs ere ENE tee date2. 11 9 RECOMMENDATIONS nn asic eee der ANS hate dd ss dot s dass etats dede ads dates dde sa SE OESIE lasser eds 11 ANNEX A ORLANS IN CEPT MEMBER COUNTRIES ccccsssssssccsssccccceesscccccccssscceccenscccessssscceesssssscceessssecessnsses 12 ANNEX DEFINITIONS AND ABBREVIATIONS ccccccsssscccccssssccesssssscccesssssccccessccesceesscceccssssccccesssncccessscecscensees 16 ANNEX REFERENCES essssssssosssssesnessaasesnssoossnssssoosasacencsnsonscaasesounsoossoassnsensoonsssosnasesonnsonseessasosasooasaseaddecasooncseosasosasenvenaoes 17 57 3 in the frequency band 2400 2483 5 MHz 1 PURPOSE OF THE REPORT The purpose of this ECC report is to consider the need to instigate an investigation into the mis use of ORLAN equipment in CEPT member countries and to provide information and guidance on enforcing the regulations including recommendations for market enforcement actions against the proliferation of illegal ORLANS or possible adaptation of the regulations Present regulation may lead to misuse and may also result in the potential risk of interference in the future Because of the free from charge use of the 2 4 GHz band with low priced ORLAN equipment there might be an assumed risk of misuse due to the need for point to point applications with directional antennas which might not be in conformity with the essential requirements In addition the report also provides in
3. Figure 2 Market Growth and Projection 57 7 4 3 Rationale for Potential Misuse Besides new applications possibilities for these directional RLANSs in the 2 4 GHz band using these RLANs would also result in several advantages for users as well as for manufacturers New applications Increased competition on local loop broadband access Extended range for outdoor applications Ideal for covering corridors less access points needed to cover the same area To better control the coverage in high density areas to guarantee a min throughput for all users User advantages e Less access points repeaters needed to cover the same area Reduced Installation costs less access points repeaters to be installed Manufacturer advantages e Frequency re use higher density of users in the same area Suppliers are also tempted to increase the transmission power of ORLANS to assure the bit rate as advertised to prevent complaints from their customers The introduction of 802 11g will only aggravate the problem as it is advertised at 54 Mbps but only for short ranges At longer ranges the throughput is equal to 802 1 1b links 5 DEPICTION OF POTENTIAL CHALLENGE So far no major problems of interference to existing services have been reported since the first RLAN systems were installed in 1994 but the use of directional gain antennas on RLAN systems resulting in higher e i r p levels could result in an interference po
4. Definitions Abbreviations 802 11b Wireless network standard for 2 45 GHz max 11 Mb s 802 11g Wireless network standard for 2 45 GHz max 54 Mb s CEPT Conf rence Europ enne des administrations des Postes et des T l communications DF Direction Finder DSSS Direct Sequence Spread Spectrum E LR P Equivalent Isotropic Radiated Power EC European Community ERC European Radiocommunications Committee now ECC ERM Electromagnetic compatibility and Radio spectrum Matters ETSI European T l communications Standardisation Institut FHSS Frequency Hopping Spread Spectrum HomeRF Wireless network standard Institute of Electrical and Electronics Engineers ISM Industrial scientific and medical OFDM Orthogonal Frequency Division Multiplex ORLAN Outdoor RLAN R amp S Rhode und Schwarz R amp TTE Radio Terminal Telecommunication Equipment RLAN Radio Local Area Network SRD Short Range Devices TX Transmitter WiFi Wireless Fidelity 57 Page 17 ANNEX REFERENCES 1 ERC Recommendation T R 10 01 Wide band data transmission systems using spread spectrum technology in 2 5 GHz band 21 EN 300 328 Electromagnetic compatibility and Radio spectrum Matters ERM Wideband Transmission systems Data transmission equipment operating in the 2 4 GHz ISM band and using spread spectrum modulation techniques Harmonized EN covering essential requirements under article 3 2 of the R amp TTE Directive 3 ERC Re
5. 24 were installed with a directional antenna with up to 24 dB gain 24 operated in the frequency band 2400 2483 5 MHz 4 were used for commercial services to third parties 70 used FHSS and 30 used DSSS explain Bluetooth and 802 11b RLAN based on DSSS 2 sets operated within the licensed transmitter power of 100 mW 1 10 operated with more power Of the remaining 13 sets the transmitter power could not be accurately determined On basis of these results Radio Agency organized a meeting with the suppliers of O RLAN equipment During this meeting the Radio Agency explained the regulations concerning O RLANSs and the risks users take in using this frequency band for vital network connections During the last year the Netherlands Radio communications Agency received 4 complaints about interference in this frequency band Three of these complaints were due to ISM equipment operating in this frequency band Only 1 complaint was caused by interference due to a high power O RLAN in the vicinity of the interfered O RLAN This problem was solved by choosing a different DSSS channel Field inspectors of the Dutch Radio Agency encountered the following difficulties during their inspections Field strength measurements of air were proved to be unreliable due to reflections multi path propagation and the inaccessible location of the transmitter aerials e Power measurements using a power meter or a directional coupler Since this
6. DEC 01 07 Radio LAN Short Range Devices in 2400 2483 5 MHz 2 ERC Report 109 Compatibility of Bluetooth with other existing and proposed radiocommunication systems in the 2 45 GHz frequency band 3 ECC Report 011 Strategic Plans for the future use of the frequency bands 862 870 MHz and 2400 2483 5 MHZ for Short Range Devices 4 EN 300 328 Electromagnetic compatibility and Radio spectrum Matters ERM Wideband Transmission systems Data transmission equipment operating in the 2 4 GHz ISM band and using spread spectrum modulation techniques Harmonized EN covering essential requirements under article 3 2 of the R amp TTE Directive 5 EN 301 489 1 Electromagnetic compatibility and Radio spectrum Matters ERM ElectroMagnetic Compatibility EMC standard for radio equipment and services Part 1 Common technical requirements 6 EN 301 489 17 Electromagnetic compatibility and Radio spectrum Matters ERM ElectroMagnetic Compatibility EMC standard for radio equipment and services Part 17 Specific conditions for 2 4 GHz wideband transmission systems and 5 GHz high performance RLAN equipment 7 ES 202 131 Receiver Parameter of Wideband Data Transmission Systems for Spectrum Planning Purposes The Harmonized European Standard EN 300 328 covers IEEE 802 11 802 11b 802 11g Bluetooth and HomeRF equipment includes these parameters and the respective measurement methods necessary for the declaration of conformity with the E
7. as part of work programme to check installations Nearly all the respondents allow the use of fixed links in the band 2400 2483 5 MHz Field force staffs in the Netherlands and France have proved that when directional antennas are used the power limit is nearly always surpassed 57 Page 10 Apart from a large number of suppliers of directional antennae there is ample information on how to build a 2 4 GHz antenna available on the Internet The UK Radiocommunications Agency now subsumed into the Office of Communications has tested some of these designs and found they gave up to 8 dB gain So far there are a negligible number of complaints about interference 7 CONSEQUENCES Maintaining the integrity of the 2 4 GHz spectrum and a fair and balanced situation for all applications is important for regulators and market participants users operators as well as sellers and installers Users will turn away from new products and services if new facilities being rolled out fail to operate due to misuse and pollution of the spectrum Recommended actions for regulators include The market participants need to be better informed about the regulatory environment This target could be achieved by organizing meetings with suppliers and trade organizations Information on the internet for users on how to access technical information for specific products and configurations with regards to the declaration of conformity newslet
8. sometimes with a 10dB power amplifier in between These stations could reach distances of up to 30 km which makes them not LOCAL but REGIONAL Portuguese Legal Framework In Portugal RLANS are allowed to operate in the frequency band 2400 2483 5 MHz with an e i r p not exceeding 100 mW and integrated or dedicated antenna as mentioned in ERC DEC 01 07 If they comply with these requirements then they are exempted from licensing and can be used in a non interference basis These requirements are part of our SRD interface specifications and are also part of Administrative Rule 217 2001 which adopts most of ECC REC 70 03 and regulates licence exemption for several types of equipment including SRD The definitions of integrated antenna non removable antenna and dedicated antenna removable antenna delivered with the equipment are also included in the abovementioned Administrative Rule Enforcement Enforcement of Portuguese legislation for these devices has two components Market surveillance RLANs are in the scope of R amp TTED and if they comply with the Directive Member States cannot impede placing on the market If there are restrictions for use in a certain country information to the user mentioning that should be available in the package and in the user s manual Monitoring surveillance actions and response to complain RLANs must not interfere with licensed emergency or security stations Complains are investiga
9. the IT department of La Rochelle had a background of network and computer technology and were ignorant about RF terminology and regulations 57 Page 15 The RegTP performed during the 4 quarter 2003 measurements at ORLANS in Berlin Hamburg Munich and the Ruhr area Main Results 1 The e i r p limit of 20 dBm was exceeded in most ORLAN cases The limit of 100 milliwatts was regularly exceeded by about 6 dB to 10 dB with exceptions even higher 2 Main reason for illegal operation was the use of a directive antenna without reducing the output power accordingly This was despite of the fact that the operators were aware of the regulatory restrictions Private operators even use self made antennas Several fora were found in the Internet that provides construction manuals 3 The results were comparable to the ones from ANFR 4 Field inspectors were surprised by the existing high usage density of 2 4 GHz ORLAN in the cities This can be monitored by means of e g a software tool lt lt Netstumbler gt gt 5 Several different devices showed a transient response during settling time measured according to EN 300 328 clause 7 2 with excessive output power up to 10 15 dB higher than during operations 6 In most cases the operation of the equipment was not protected at all 7 More measurements campaigns needed in future 57 Page 16 ANNEX DEFINITIONS AND ABBREVIATIONS
10. AN services 2003 203 EC confirmed the above circumstances 3 1 Users manual In article 6 1 and 6 3 of the Directive 99 5 EC the need for clear instructions to the installer and user is stated Directive 99 5 EC of the European parliament and of the Council of 9 march 1999 Article 6 1 Member States shall ensure that apparatus is placed on the market only if it complies with the appropriate essential requirements identified in Article 3 and the other relevant provisions of this Directive when it is properly installed and maintained and used for its intended purpose It shall not be subject to further national provisions in respect of placing on the market 3 Member States shall ensure that the manufacturer or the person responsible for placing the apparatus on the market provides information for the user on the intended use of the apparatus together with the declaration of conformity to the essential requirements Where it concerns radio equipment such information shall be sufficient to identify on the packaging and the instructions for use of the apparatus the Member States or the geographical area within a Member State where the equipment is intended to be used and shall alert the user by the marking on the apparatus referred to in Annex VII paragraph 5 to potential restrictions or requirements for authorisation of use of the radio equipment in certain Member States Where it concerns telecommunications terminal equipment such informat
11. commendation 70 03 relating to the use of Short Range Devices SRD 4 ERC DEC 01 07 ERC Decision of 12 March 2001on harmonised frequencies technical characteristics and exemption from individual licensing of Short Range Devices used for Radio Local Area Networks RLANS operating in the frequency band 2400 2483 5 MHz 5 ERC Recommendation 74 01 relating to Spurious emissions
12. formation for the market surveillance authorities on the legal use of 2 INTRODUCTION The market for local area networks using short range radio links is growing rapidly Most current equipment is operating in the 2 4 GHz industrial scientific and medical ISM band using the IEEE 802 11b 802 11g standards as well as the Bluetooth and HomeRF specifications This band has the advantage of being available worldwide on a licence exempt basis but is expected to congest rapidly as RLANs are deployed continuously In 1991 CEPT issued Recommendation T R 10 01 1 concerning the regulatory constraints under which RLANs could be deployed in the 2 4 GHz frequency band ETSI followed up on this and published ETSI EN 300 328 2 In the meantime CEPT recommendation T R 10 01 has been replaced by the Recommendation 70 03 3 covering RLANs as well as other SRD devices ERC Decision 01 07 4 has been implemented for the use of RLANs in the 2400 MHz to 2483 5 MHz ISM frequency band Until now 24 CEPT administrations have implemented this decision in their countries Almost all administrations allow the use of the frequency band but some administrations limit the use only to indoor or private use Some still require an individual licensing regime In 2000 ETSI asked the CEPT ERC to change current regulation to allow 1 levels up to 500 mW with directional antenna using the same 100 mW transmitter power However ERC did not ag
13. ible locations the measurements are severely hampered due to reflections and inaccurate distance between the antennas Disconnecting links causes operational unavailability and financial loss for the users In most cases during a rooftop inspection the use of a highly directive antenna in combination with known transmitter parameters is sufficient to conclude that the set is not in compliance with the regulations A better assumption can be achieved if all gains and losses of involved technical entities e g transmitter connectors cables antenna are considered 57 Page 11 8 CONCLUSIONS There is a big demand for Point to Point and Point to Multipoint links Suppliers and network installers are very creative in meeting this demand by using licence exempt equipment without proper knowledge and understanding of the applicable regulations The only available information for the end user is the user s manual of the transmitter However the manufacturer or the person responsible for the placing of the apparatus on the market has no influence on the use of a particular type of directive antenna The European Commission has recommended in their Commission Recommendation of the 20 March 2003 2003 203 EC that Member States should not make use of the available 2 4 GHz band for the operation of RLAN systems subject to the grant of any individual right In addition it would only be in line with the European C
14. ion shall be sufficient to identify interfaces of the public telecommunications networks to which the equipment is intended to be connected For all apparatus such information shall be prominently displayed Therefore a manufacturer has to provide information that the product can be used in all countries following the EU directive 99 5 EC without any limitation except for specific country restrictions which need to be clearly provided For ORLANS with integral antennas this also includes the following information 1 Depending on the type of antenna used it might be necessary to reduce the output power of the equipment to result in a maximum radiated power of 100 mW eirp or less 2 Combinations of power levels and antennas resulting in a radiated power level above 100 mW are considered as not compliant with national radio interface regulation of the countries that have implemented the ERC Recommendation 70 03 and are not allowed for use within these countries Some countries allow higher than 100 mW e i r p on an individual licensing regime In such a case the ORLAN is not covered anymore by the abovementioned conditions which are for Short Range Devices However this is the case only if the conformity assessment was made for the combination of equipment and antenna and if both are sold together It is not the case if the equipment is sold without antenna It is the responsibility of the user to don t exceed the allowed maximum power It is
15. kind of measurement requires the equipment to be turned off to enable the inspector to install the measurement equipment the users objected that their network operations would suffer severely Also they required guarantees that their network operations would resume normal working after the tests were performed These guarantees could not be given e Since this inspection a licence is no longer required the Radio Agency no longer has any knowledge about the location of ORLANs 57 Page 13 Placing on market A quick survey of the availability of the equipment was performed The O RLAN components are freely available in several price ranges The intended use varies between access points with integrated antennas for a home network to professional equipment with external antennas and adjustable power settings Remarkable in this survey is that most suppliers of this equipment are specialists in computer or network installations They have a very limited understanding of the particulars of RF equipment and the pitfalls of installing RF components Especially the risks of combining a 2 4 GHz transmitter of 100 mW with an aerial with 24 dB gain are unknown Site coordination procedures site clearance procedures OOB Emissions normally do not remain in compliance with the limits in ERC REC 74 01 Be aware of stricter limits for SRDs in Broadcast Frequency Ranges Class 1 Directional antennas with up to 24 dB gain are f
16. nd ISM in compliance with footnote 5 150 of the Radio Regulations This report focuses on Outdoor Radio Local Area Networks O RLAN covered by the regulations for short range devices Until June 2002 a licence was required for the use of Outdoor RLAN In this licence it was stated that transmitter power of O RLANSs was limited to 100 mWatt e i r p Since June 2002 a new Nationaal Frequentieplan national allocation table was issued and a licence for O RLAN was no longer required During the first half of 2002 the Dutch Radio Agency received information from network operators and suppliers of O RLAN equipment regarding interference caused by O RLANs transmitting over 100 mW e ir p This information triggered the Dutch Radio agency to inspect a number of O RLAN installations of licence holders There were 194 licenses issued in the Netherlands for O RLANSs Of this group 25 licence holders were selected for an inspection The inspection consisted of a questionnaire and a physical inspection of the transmitter and antenna Analysis of the questionnaire led to the conclusion that most licence holders or users are unfamiliar with the regulations applicable to O RLANSs and also that they were unable to answer the questions pertaining to the technical parameters of the equipment they used Results of the physical inspection was that of the 25 installations All were used for fixed Point to Point connections All were used 24 hours a day
17. ng Yes 100 mW only on the frequency band 2400 2454 Mhz 10 mW only on the frequency band 2454 2483 5 Mhz Rooftop inspections performed with the agreement of the user SHF equipment EB 200 spectrum analyser with dish antenna Even if the regulation is not yet stable in France public prosecutions might be introduced against illegal uses Yes 100 mW e i r p only ORLAN measurements performed in Q4 2003 EB200 High gain DF up to km from TX There is an enforcement procedure to find them Indoor and private only Yes 100 mW e i r p only Yes EB200 Yes 100 mW e i r p only Considered EB200 and visual inspection of rooftops 4 complaints only 1 due to high power O RLAN Yes 100 mW e i r p only 200 and applicable antennas Visual inspection of rooftops Only a few complaints yet Yes 100 mW e i r p only No Not planned Not yet defined Use only with integrated or dedicated antennas allowed Yes IA few lt 5 Not planned Complaints are in general not investigated since protection against interferences is not given in the bands freed from licensing Yes 100 mW e i r p only Advantest 3641 R amp S FSP7 or 200 Only 1 complaint Yes 100 mW e i r p only Complaints are about unfair competition with concern about home made antennas and over power Inspections will be made
18. noted that RLAN equipment which is operated in the frequency band from 2446 5 MHz to 2483 5 MHz and limited to indoor application only is included in the Class 1 category for radio devices as published by the European Commission in their official newsletter for placing radio equipment on the market If equipment applies to Class 2 category restrictions on usage have to be included in the manual 57 5 3 2 Technical parameters Modulation Frequency Hopping Spread Spectrum Modulation Direct Sequence Spread Spectrum Modulation and similar modulations e g OFDM Maximum e i r p 100 mW FHSS 100 mW 100 kHz DSSS 10 mW 1MHz Spurious emissions According to CEPT ERC REC 74 01 Maximum Power Flux Density Table 1 Technical Parameters The term Short Range Device SRD is intended to cover radio transmitters which provide either uni directional or bi directional communication and which have low capability of causing interference to other radio equipment SRDs use integral dedicated or external antennas and all modes of modulation can be permitted subject to relevant standards The CEPT Recommendation 70 03 describes the spectrum management requirements for SRDs relating to the allocated frequency bands maximum power levels channel spacing and duty cycle In addition to Rec 70 03 for in the 2400 MHz to 2483 5 MHz frequencies the following documents apply 1 ERC
19. ompetition Rules if the same general authorisation rules would be imposed to all users in this category The main reason for illegal operation is the use of a directive antenna without reducing the output power accordingly Market enforcement found that this was despite of the fact that the operators were aware of the regulatory restrictions Private operators even use self made antennas Recent inspections showed that the usage density especially in urban areas is increasing quickly However due to the exponential growth of the market it is hardly possible to make predictions on the amount of future complaints It can only be assumed that the problem will spread to areas and countries not having seen complaints yet Because of similar use and design of Outdoor RLAN equipment in the 2 4 GHz as well as 5 GHz frequency range and by taking into account that the market for 5 GHz RLAN has just commenced to be developed it can be expected that market enforcement will face the same problems with 5 GHz Outdoor RLAN in future 9 RECOMMENDATIONS National investigations in the use of directional antennas and the transmission power of ORLAN equipment is recommended Based on the conclusions the need for enforcement actions against the proliferation of ORLANs with an improper combination of output power and directional antenna or adaptation of the regulations should be considered Adaptations of the regulations need also to address concerns and complain
20. ree to allow 500 mW 1 ERC concluded that increased e i r p limit for RLANs would lead to a further congestion in the 2 4 GHz band In general the use of higher radiated power tends to block other applications in the same frequency band 3 REGULATORY ENVIRONMENT AND TECHNICAL PARAMETERS The regulatory parameters for the use of RLANs can be found in ERC Recommendation 70 03 on Short Range Devices Annex 3 In addition the restrictions on the use of RLAN in some CEPT member countries are listed in Appendix 3 of this recommendation As such RLANs are operated on a licence exempted and non protected basis following Art 4 4 of the Radio Regulations since it is operated in an ISM frequency band The risk of interference between the various different users who may share the 2 4 GHz band and between coexisting RLAN systems has to be accepted by the parties involved As long as RLAN users do not cause harmful interference to possible protected users in the same band the use of the frequency band should not be subject to individual rights nor to the extent possible to general authorisation conditions other than currently allowed This includes the right for national authorities to impose general authorisation conditions where justified in a proportionate manner for all users in the band having the same status 57 Page 4 The European Commission in their recommendation on the harmonisation of provision of RL
21. reely available in several price ranges On the Internet a quick search resulted in a multitude of companies producing said aerials The sale of these aerials is not restricted Problems in enforcement are encountered due to the fact that RLAN equipment with external antennas can be equipped with any type of aerial that is available The rules and regulations do not require a dedicated antenna in combination with the transmitter The R amp TTE directive stipulates that the sale of equipment conforming to the essential standards cannot be restricted The transmitters are in compliance with this directive Antennas are not covered by the R amp TTE Directive Only the combination of both results is a breach of the applicable rules and regulations governing this frequency band United Kingdom In the UK the band 2400 2483 5 MHz is allocated for the use of RLANs on a licence exempt basis This allocation is specified in UK Interface Requirement IR 2005 which permits a maximum e i r p of 100 mW in accordance with Recommendation 70 03 This allocation is understood to be on a non interference no protection basis and accordingly OFCOM does not take active measures to police the band but will investigate complaints relating to alleged use of non conforming equipment If such equipment is found to be in operation OFCOM will take action to ensure that transmission ceases and the offending equipment is removed Anecdotal evidence suggests that illegal equipmen
22. ssential Requirements under Article 3 2 of the R amp TTE Directive 99 5 EC 57 Page 6 4 MARKET INFORMATION 41 Placing on the market The EC has published guidance documents for those placing on the market which can be found at http europa eu int comm enterprise rtte gener htm 4 2 Market Data and Tendency The ORLAN market is estimated in Figure 2 Examples of tangible benefits yielded by advanced applications of R LAN technology include e Wireless connection of Local Area Network infrastructure between buildings on Campuses or in Metropolitan areas delivers high quality flexible and cost effective alternatives to tariff based lease line services e Increased alternatives for wireless data services in unlicensed operation resulting in increased competitive substitutes for tariff based cellular services e Broadband Internet access in rural areas where ADSL of cable is not yet available Market Development for 802 11b in 2 4 GHz indicates a strong growth Market projections for 2006 indicates 20 million users whereas the existing customers based at the end of 2002 was only 1 million customers on a worldwide basis These figures are for 802 11b WIFI equipment only and do not include Bluetooth and others At year end 2003 Bluetooth equipment was shipped across the world at the rate of approximately 1 million units per week 1 mover in M 2001 2002 2003 2004 2005 2006 Source Frost amp Sullivan
23. t may be more widely used than it is found Equipment compliant to IR 2005 may be used to provide fixed links and indeed is widely used in this configuration in the UK especially in the education sector All equipment configurations must comply with the IR 2005 maximum e i r p limit whether directional antennas are employed or not OFCOM has recently become aware of widespread dissemination of information relating to self build antennas made of household waste principally metal packaging that are claimed to provide significant gain As a research project some of these were constructed according to information found on the Internet The initial results of this work show that with extremely cheap and easily obtainable materials it is possible to make a simple antenna giving around 8 dB of gain This has implications for the use of this band OFCOM therefore will take enforcement action in future against any installation where these antennas are found if their use exceeds e i r p limits of IR 2005 57 Page 14 Portugal Subject equipment that complies with R amp TTE Directive but cannot eventually be placed on the Portuguese market nor used Introduction RLANS are used more and more all over Europe and sometimes its use does not comply with the purposes for which they were created The issue was raised when several RLANs were detected in The Netherlands for example using directional antennas with up to 24dB gain
24. ted in order to determine the origin and the characteristics of the interfering signal Practical case An RLAN equipment in the frequency band 2400 2483 5 MHz with e i r p not exceeding 100 mW delivered without an integrated antenna and with an external socket CE mark etc is put on the Portuguese market The package shows no information to the user warning him for restrictions in Portugal Possible Action This equipment cannot be used without an integrated or dedicated antenna and cannot be placed in the market unless there s a warning to the user But even if there was such a warning saying for example that this equipment must be used with a dedicated or integrated antenna that wouldn t make sense because by definition integrated or dedicated antennas should have been included in the equipment package France An inspection of a community RLAN network in the town of La Rochelle gave the following results The builder of the network was convinced the network was within the regulations because he used transmitters with 50 mWatt power However these transmitters were combined with directional antennae with up to 30 dB gain resulting in over 30 Watt 1 To measure the power there has to be a continuing data stream available to guarantee a constant transmission Only reliable method proved to be calculating the 1 on basis of transmitter parameters antenna gain and cable loss The personnel of
25. tempted to increase their own transmitter power and this again will lead to more noise 6 COUNTRIES EXPERIENCE WGRA RA11 has performed an investigation and requested information on the use of ORLANSs and the enforcement of the applicable rules and regulations in the CEPT member countries The questionnaire contained the 5 following questions 15 the use of Fixed Links in the frequency band 2400 2483 5 MHz allowed in the CEPT member countries Is the use of directional antennas in combination with O RLANSs allowed Are there complaints about interference Is your administration planning enforcement action against this application If you are planning preventive actions what kind of monitoring or DF equipment will your agency be using Fixed links Directional antenna Complaints Enforcement actions Equipment ECC REPORT 57 Page 9 Remarks Yes Yes 100 mW e i r p only No Yes Actions based on suspicious advertisements and by looking at rooftops for suspicious antennas Yes 100 mW 1 only Planned in 2004 Yes 100 mW e i r p only Not planned Visual inspection of rooftops ORLANS require Licence Preventive actions are considered to be ineffective Yes but 100 mW e i r p only Not planned Yes 100 mW e i r p only Not planned Complaints in general are not investigated since protection against interferences is not given in the bands freed from licensi
26. tential that is above the current interference potential Increasing the radiated output power does increase the operating distance and therefore increases the probability of interference to existing services in this direction On the other hand the interference probability at the backend of the directional antenna is reduced The drawing below illustrates how using a directional antenna changes the shape over the covered area but not the size if conducted power remains the same In this example the operating distance is approximately doubled by increasing the e i r p from 100 mW to 500 mW by using an directional antenna with a gain of 7 dBi It is relatively easy to connect antennas with gains of 20 to 30 dBi In these cases the operating distance would be increased to 10 x r and 33 x r respectively 57 Page 8 Antenna 100 mW Tx out 100 mW eirp Antenna Location Identical areas in both scenarios but different antenna locations a Directional Antenna mW Tx out 500 MW eirp Figure 1 Increase of Operating Distance by Using a Directional Antenna In addition the consequence of transmitting with higher power levels 100 mW output power in connection with a directive antenna will lead to an increase of the noise level in this frequency band The quality of the services in this band will be reduced To counteract this effect the users of impacted systems are
27. ters brochures or other means of providing the necessary information pertaining to ORLANSs is very also helpful Enforcement Actions It should be necessary to improve the national Enforcement activities Preventive actions based on normal spectrum monitoring are deemed to be ineffective Especially when trying to find fixed links using directive antennas Rooftop inspections to find these external antennas are more useful especially when there are complaints Inspectors have to be instructed to be on the alert for suspect antenna configurations Market surveillance Actions A less intrusive action is an administrative inspection i e checking the necessary documentation that must be supplied by the party that integrated the link components art 6 3 of the R amp TTE Directive A regulatory authority can also conduct from time to time a measurement campaign in order to find out the real market environment and to manage a better estimation of the actual misuse Advertisements promoting the illegal use of ORLAN need to be followed actively by the authorities Interference Complains In the case of a justified complaint due to equipment being used illegally the regulatory authority has the right to force the user to stop transmission or cease operation Technical Enforcement actions Encountered difficulties Experiences Power measurement on rooftops is very difficult Besides the fact that the antennas are mounted on inaccess
28. ts from the market participants over unfair competition Industry and operators need to be adequately informed by the administrations about the regulations with the aim to reduce the misuse of ORLAN equipment It is recommended that WGFM should be informed of the situation and the assumed risk of misuse due to the need for point to point applications WGFM might consider the demand for a separate frequency band for un coordinated point to point installations under general authorisation with no individual rights operation ECC REC T R 22 03 should be considered on whether or not it could provide a solution to satisfy this demand Since the main reason for illegal operation is the use of a directive antenna without reducing the output power it should also be considered whether the regulations can suffice with a specification of transmitter output power in combination with a rule that relates the scaling of transmitter output power and antenna gain Such a regulation would take into account that ORLAN equipment is normally designed to have an antenna connector and that transmitter and antenna are often not sold together Hence it has a potential to reduce misuse of ORLAN equipment 57 Page 12 ANNEX A ORLANS IN CEPT MEMBER COUNTRIES The Netherlands In the Netherlands the frequency band 2400 2483 5 MHz has been allocated to the mobile communication service electronic newsgathering outside broadcast short range devices a
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