1、QUESTION ITU-R 202-3/5*,*Unwanted emissions of primary radar systems(1993-1997-2001-2004)The ITU Radiocommunication Assembly,consideringa) that the radio spectrum available for use by the radiodetermination service is limited;b) that the radionavigation service is a safety service as specified by No
2、 4.10 of the RadioRegulations (RR), and in addition that some other types of radar systems such as weather radarsmay perform safety-of-life functions;c) that the necessary bandwidth of emissions from radar stations in the radiodeterminationservice is large in order to effectively perform their func
3、tion;d) that new emerging technology systems may use digital or other technologies that are moresusceptible to interference from unwanted emissions from radar systems due to their high peakenvelope power;e) that Radiocommunication Study Group 8 has been studying the question of efficient use ofthe r
4、adio spectrum by radar systems including the study of inherent unwanted emissioncharacteristics of various types of output devices;f) that Radiocommunication Study Group 9 completed studies on the effects of unwantedemissions from radar systems on systems in the fixed service and developed Recommend
5、ationsITU-R F.1097 on “Interference mitigation options to enhance compatibility between radar systemsand digital radio-relay systems” and ITU-R F.1190 on “Protection criteria for digital radio-relaysystems to ensure compatibility with radar systems in the radiodetermination service”;g) that unwanted
6、 emissions from radar systems may in some cases cause unacceptableinterference to systems in other radio services operating in the adjacent and harmonically relatedbands (see Appendix 3, 11 of the RR);h) that performance (bandwidth, coherency, etc.), expected lifetime, cost, weight, size andmechanic
7、al ruggedness are important factors that must be considered in the design-to-performancespecifications of radiodetermination systems;j) that Radiocommunication Study Group 1 has revised Recommendation ITU-R SM.329which includes spurious emission limits for the radiodetermination service;_* This Ques
8、tion should be brought to the attention of Radiocommunication Study Group 1, the InternationalAssociation of Marine Aids to Navigation and Lighthouse Authorities (IALA), the International MaritimeOrganization (IMO), the International Civil Aviation Organization (ICAO), the International MaritimeRadi
9、o Committee (CIRM), and the World Meteorological Organization (WMO).* Former Question ITU-R 202-3/8.- 2 -k) that Radiocommunication Study Group 1 has developed Recommendation ITU-R SM.1541on out-of-band emission limits which includes amongst others out-of-band emission limits for theradiodeterminati
10、on service outside their exclusive bands;l) that WRC-2000 revised Appendix 3 Table of Maximum Permitted Spurious EmissionPower Levels based on Recommendation ITU-R SM.329, and decided that radiodeterminationservice transmitters installed after 1 January 2003 and all transmitters after 1 January 2012
11、 mustcomply with these power levels;m) that Radiocommunication Study Group 8 has developed Recommendation ITU-R M.1177on techniques for measurement of unwanted emissions of radar systems;n) that Radiocommunication Study Group 8 has developed Recommendation ITU-R M.1314on reduction of spurious emissi
12、ons of radar systems operating in the 3 GHz and 5 GHz bands,notingthat the out-of-band limits in bands allocated to the radiodetermination service on an exclusive basisare under the purview of Study Group 8,decides that the following Questions should be studied1 What are the unwanted emission levels
13、 from existing and state-of-the-art radar systemstaking into account:a) type and size of the platform (e.g. fixed, mobile, shipborne, airborne, etc.);b) available technologies; andc) economic considerations?2 What mitigation options, such as the choice of output device, could be taken intoconsiderat
14、ion in the design and implementation of radar systems to reduce radar unwantedemissions, and what are their associated impacts on operational performance (bandwidth,coherency, etc.) expected lifetime, relative cost, weight, size and mechanical ruggedness?3 What unwanted emission levels can be achieved using these mitigation options, and whatcompatibility can then be achieved with other radio services?further decides1 that the results of the above studies should be included in (a) Recommendation(s);2 that the above studies should be completed by 2007.Category: S2
