1、104 - - ITU-R RECMN*SA- 1154 35 W 4855212 0524155 bTL W Rec. ITU-R SA.1154 RECOMMENDATION ITU-R SA. 1 154* PROVISIONS TO PROTECT THE SPACE RESEARCH (SR), SPACE OPERATIONS (SO) AND EARTH-EXPLORATION SATELLITE SERVICES (EES) AND TO FACILITATE SHARING WITH THE MOBILE SERVICE IN THE 2025-2110 MHz AND 22
2、00-2290 MHz BANDS (1995) The Radiocommunication Assembly, considering a) that the bands 2 025-2 110 MHz and 2 200-2 290 MHz are allocated on a primary basis to three of the space science services (SR, SO, EES), the fixed service (FS) and the mobile service (MS) subject to the provisions of No. 747A
3、of the Radio Regulations (RR); b) that the World Administrative Radio Conference for Dealing with Frequency Allocations in Certain Parts of the Spectrum (Malaga-Torremolinos, 1992) (WARC-92). in its Resolution No. 211, invites the ex-CCIR to continue to study appropriate provisions to protect the sp
4、ace science services operating in the bands 2025-2 110 MHz and 2 200-2 290 MHz from harmful interference from emissions by stations of the mobile service and to report the results of studies to the next competent conference; cl that there is an increasing use of SR, SO and EES services in these freq
5、uency bands by space stations in low- Earth orbit (LEO); d) that the ex-CCIR report on the technical and operational bases for WARC-92 concluded that the introduction of future high density or conventional land mobile systems in the 2 025-2 110 MHz and 2200-2290 MHz bands would cause unacceptable in
6、terference to the SR, SO and EES services; for further information see Annex 1; e) that studies indicate that specific low density mobile systems, such as those described in Annex 2, could share the 2 025-2 1 10 MHz and 2 200-2 290 MHz bands with the SR, SO and EES services; f that in some countries
7、 the space science services have successfully shared for many years with low density mobile electronic news gathering (ENG) systems (see Annex 3) and aeronautical mobile telemetry systems (see Annex 4) without restrictions, however, restrictions may be needed in the future considering the expected g
8、rowth rate of these systems; 9 that space science service operations in the band 2 200-2 290 MHz are more vulnerable to interference than operations in the band 2 025-2 110 MHz because of high gain antennas of geostationary data relay satellite (DRS) spacecraft pointing towards the Earth when tracki
9、ng a low-Earth orbiting spacecraft; h) that the protection criteria required for the SR service are the most stringent of the three space science services and provide adequate protection for the SR, SO and EES services; j) that Recommendation ITU-R SA.609 (5 1, 1.1, 1.2 and 2) specifies the protecti
10、on criteria for the SR service; k) that the protection criteria of Recommendation IT-R SA.609 have been used repeatedly in sharing studies and are widely recognized; 1) that SR, SO and EES services use the 2 025-2 110 MHz and 2 200-2 290 MHz bands for Earth-to-space, space- to-Earth and space-to-spa
11、ce radiocommunications. The space-to-space links typically include the use of a DRS as described in the hypothetical reference system in Recommendations ITU-R SA.1020 and ITU-R SA. 101 8. The sharing criteria should consider the protection requirements of DRS radiocommunication links operating in th
12、e 2 025-2 110 MHz and 2 200-2 290 MHz bands; * This Recommendation should be brought to the attention of Radiocommunication Study Groups 4, 8 and 9. COPYRIGHT International Telecommunications Union/ITU RadiocommunicationsLicensed by Information Handling Services- ITU-R RECMNxSA- 3354 75 a 4855232 O5
13、24356 538 Rec. ITU-R SA.1154 105 m) resulting in a 1 dB degradation is considered sufficient in most cases; that for the protection of SR, SO and EES services, Earth-to-space and space-to-Earth links, a NII of 6 dB, n resulting in a 0.4 dB degradation is considered necessary for DRS space-to-space l
14、inks; that, taking into account the typically low margins on space-to-space links of 2 dB and less, a NII of 10 dB, 0) that the bands under consideration are shared with the FS and the MS. Each service is assumed to contribute half of the total interference to the spacecraft. Due to expected coordin
15、ation only one of the services is assumed to interfere with an earth station; P) that DRS spacecraft are typically located on the geostationary orbit (GSO); 4) that the 2 025-2 110 MHz band is used for SR, SO and EES Earth-to-space links to both low-Earth orbiting and GSO spacecraft. This band is al
16、so used for SR, SO and ESS space-to-space links, typically for radiocommunications from DRS spacecraft to low-Earth orbiting spacecraft; r that the 2 200-2 290 MHz band is used for SR, SO and EES space-to-Earth links from both low-Earth orbiting and GSO spacecraft. This band is also used for SR, SO
17、and EES space-to-space links, typically for radiocommunications from low-Earth orbiting spacecraft to DRS spacecraft; s) distribution of systems, that terms concerning the density mobile systems refer to the number of systems and the population recognizing 1 that specifying a maximum number of mobil
18、e stations worldwide operating in the 2 025-2 110 MHz and 2 200-2 290 MHz bands such that the aggregate interference level does not exceed the sharing criteria may constitute a valid technical solution. However, the implementation of such a solution may not be practical, further recognizing 1 that i
19、t is a unique combination of technical and operational characteristics of specific mobile systems that facilitate sharing, and sharing between such mobile systems and the SR, SO and EES services can be described in both qualitative and quantitative terms, recommends 1 from emissions of mobile system
20、s in the 2 025-2 1 10 MHz band: that the following provisions are suitable to protect the SR, SO and EES services from aggregate interference 1.1 space link, should not exceed -180 dB(W/kHz) for more than 0.1% of the time; that the aggregate interference at the input terminals of the spacecraft rece
21、iver, except in the case of a space-to- 1.2 receiver should not exceed -184 dB(WlkHz) for more than 0.1% of the time; that in the case of space-to-space links the aggregate interference at the input terminals of the spacecraft 2 from emissions of mobile systems in the 2 200-2 290 MHz band: that the
22、following provisions are suitable to protect the SR, SO and EES services from aggregate interference 2.1 -216 dB(W/Hz) for more than 0.1% of the time; that the aggregate interference at the input terminals of the receiver in the earth station should not exceed 2.2 -184 dB(W/kHz) for more than 0.1% o
23、f the time; that the aggregate interference at the input terminals of the DRS spacecraft receiver should not exceed 3 that in accordance with Resolution No. 211 (WARC-92) high density or conventional type mobile systems should not be introduced in the 2 025-2 110 MHz and 2 200-2 290 MHz bands, becau
24、se they will cause unacceptable interference in the SR, SO and EES services as confirmed in Annex 1; COPYRIGHT International Telecommunications Union/ITU RadiocommunicationsLicensed by Information Handling Services ITU-R RECMNrSA. 3354 75 W 4855232 0524357 474 W 106 Rec. ITU-R SA.1154 4 would not ca
25、use aggregate interference levels in excess of the values given in 0 1 and 2; that new mobile systems should be introduced in such a way that their long term, worldwide deployment 5 densities and intermittent transmissions (see Annex 2) be preferred for the introduction of new mobile systems; that t
26、echnical and operational parameters such as low power spectral densities, low Worldwide population 6 technical and operational characteristics, similar to those described in Annex 3, should be used for guidance; that during the consideration of new low density mobile systems for introduction in the
27、2 025-2 110 MHz band, 7 technical and operational characteristics, similar to those described in Annex 4, should be used for guidance. that during the consideration of new low density mobile systems for introduction in the 2 200-2 290 MHz band, , L ANNEX 1 Compatibility study of space researcWspace
28、operations and high density land mobile systems 1 Introduction WARC-92 concluded that sharing between high density and conventional land mobile systems on the one hand and space services on the other hand is not feasible. This Annex is based on contributions which lead to this conclusion and provide
29、s the underlying analysis. The mobile system considered in this study is the future public land mobile telecommunication system (FPLMTS), as defined in the studies leading to WARC-92. The model used is also applicable to conventional type mobile systems. The bands 2025-2 110 GHz and 2200-2290 MHz ar
30、e intensively used for space operations, Earth exploration by satellite, and space research on a worldwide basis with numerous agreements for international cross-support among space agencies. Due to the long distances between transmitters and receivers, signal levels at the receivers are very low. c
31、onsequently these services are very sensitive to interference requiring high protection levels as specified in the RR and IT-R Recommendations. Figure 1 shows the various links considered and the resulting interference configurations. Only voice services are con- sidered for the personal and mobile
32、stations. Additional interference from base stations has not been studied yet. At present it is already a challenge for frequency managers to satisfy new assignment requests for the currently allocated space services in such a way as to minimize interference impacts on existing assignments. Conseque
33、ntly, intra-service sharing with additional users becomes increasingly difficult. In the case of mobile services antenna patterns are quasi omnidirectional and the envisaged tens of millions of mobile transmitters have a very high cumulative interference level. As FPLMTS units are “mobile“ by defini
34、tion, coordination is not possible for obvious reasons. It can be demonstrated that for practically every configuration considered, sharing with these mobile systems is not feasible. 2 Radio regulatory and band occupation aspects WARC-92 allocated the 2 025-2 1 10 MHz and 2 200-2 290 MHz bands on a
35、co-primary basis to the SR, SO and EES and the mobile service in all IT regions. COPYRIGHT International Telecommunications Union/ITU RadiocommunicationsLicensed by Information Handling Services 4 IITU-R RECMNrSA. 1154 95 4855212 0524158 300 U Rec. ITU-R SA.1154 FIGURE 1 Interference configurations
36、between FPLMTS units and space senices 107 base station Interfering links - stations stations station indoors Maximum tolerable interference levels for earth stations are defined in AF28-23 to the RR, Table II and in Recommendations ITU-R SA.363 and ITU-R SA.609. Antenna diagrams for earth stations
37、are based on the radiation patterns specified in AF29-13 to the RR, Annex III. The minimum elevation angles for earth station antennas are in agreement with RR No. 2551 and RR No. 2550. Interference levels for spacecraft receivers are specified in Recommendations ITU-R SA.609 and ITU-R SA.363. In th
38、e band 2 025-2 110 MHz there are currently more than 300 assignments. In the band 2 200-2 290 MHz the number of assignments is above 350. For the space-to-space links there are currently six allocations for the data relay system with a number of additional ones in progress for the international spac
39、e station programme as well as for the European and the Japanese data relay satellite programmes. It is apparent that the bands under consideration are heavily used by space services and that a large number of satellites and earth stations would be affected by land mobile services operating in these
40、 frequency bands. COPYRIGHT International Telecommunications Union/ITU RadiocommunicationsLicensed by Information Handling Services ITU-R RECMNtSA- 1154 95 = 4855212 0524159 247 108 Rec. ITU-R SA.1154 Mobile station outdoor 3 Land mobile services (FPLMTS) system assumptions Personal Personal station
41、 station outdoor Indoor A wide range of services is foreseen for future mobile communication systems. One of the services envisaged for operation in the bands near 2 GHz is the future public land mobile telecommunication system (FPLMTS). The designated bandwidth for these services is 230 MHz. Base s
42、tation antenna height (m) Traffic density urban area (E/km2) Ceil area (km2) The FTLMTS is in the planning stage with preliminary figures on subscriber rates, traffic densities, and power levels. Radiocommunication Study Group 8 provided relatively detailed assumptions on power levels, bandwidth req
43、uirements, traffic density, etc. A summary of system assumptions provided is listed in Table 1. 50 10 3 500 (0.25) 1500 (1.2) 20000 (1.2) 0.94 0.016 O.OOO6 TABLE 1 Duplex bandwidth per channel (kHz) Traffic per cell (E) Summary of system assumptions 25 50 50 470 24 12 Number of channels per cell Ban
44、dwidth for voice services (MHz) 493 34 23 111 27 24 Station power range (W) Speech coding rate (kbit/s) 1-5 0.02-0.05 0.003-0.01 8 (16) (16) Peak-to-mean ratio for traffic Peak traffic density per station (E) (3) 3 (3) 0.1 (0.04) 0.04 (O. 1) 0.2 (0.1) Subscriber rate (penetration) (%) In some cases
45、it was found that for an average interference assessment the FPLMTS assumptions were too optimistic, in particular regarding traffic density and subscriber rate. Values quoted between brackets have been used instead. With the original FPLMTS data the interference excess values would be higher. Where
46、 no data were available the numbers between brackets have been used for the calculations. 50 (10) 80 (20) (20) Only the voice services have been taken into account but it is expected that non-voice services will result in very similar values. The traffic density assumptions for the analyses are base
47、d upon figures available for Europe. The population in all common market countries is currently around 323 million living in an area of 2.3 million km2. This leads to an average of 140 people per km2 used as a basis for interference calculation to earth stations. The traffk density assumptions for t
48、he interference scenario for spacecraft receivers can be derived in a similar way. A geostationary spacecraft “sees” an area as indicated in Fig. 3 with approximately 4 billion people living in it by the year 2000. The minimum orbit height of a spacecraft is 250 km. Figure 4 shows the area seen by a
49、 spacecraft flying at COPYRIGHT International Telecommunications Union/ITU RadiocommunicationsLicensed by Information Handling ServicesITU-R RECMN*SA. LL54 75 4855232 0524Lb0 Tb7 Rec. ITU-R SA.1154 109 orbit heights of 250 km and 750 km, respectively. The interference reception area for a 250 km orbit is already 9.6 mio km2. The population living in this area is estimated to more than 600 million people. Figure 5 shows interference reception areas for low inclination orbits around 29“ which are typical for space shuttle type orbits. Environmental attenuat
