1、 Rec. UIT-R S.1328-4 1 RECOMMENDATION ITU-R S.1328-4 Satellite system characteristics to be considered in frequency sharing analyses within the fixed-satellite service (Questions ITU-R 205/4, ITU-R 206/4 and ITU-R 231/4) (1997-1999-2000-2001-2002) The ITU Radiocommunication Assembly, considering a)
2、that a database containing the characteristics of typical systems in the fixed-satellite service (FSS) is needed for use in frequency sharing studies within ITU-R; b) that to be most readily usable such a database should be in the same format for all systems and should be available in electronic for
3、m; c) that the World Radiocommunication Conference (Geneva, 1995) (WRC-95), in Resolutions 116 (WRC-95) and 117 (WRC-95), allocated frequencies to the FSS for use by feeder links of non-GSO MSS systems; d) that WRC-95, in Resolution 118 (WRC-95), provided for parts of the 30/20 GHz bands in the FSS
4、to be used by the non-GSO FSS without the restrictions of Radio Regulations (RR) No. S22.2; e) that WRC-95, in Resolution 120 (WRC-95), provided for parts of the 30/20 GHz band in the FSS to be shared with feeder links of the non-GSO MSS; f) that WRC-95, in Resolution 121 (WRC-95), advocated the dev
5、elopment of interference criteria and methodology for sharing between feeder links of the non-GSO MSS and networks of the GSO FSS; g) that the World Radiocommunication Conference (Geneva, 1997) (WRC-97) in Resolution 130 (WRC-97), advocated the development of interference criteria and methodology fo
6、r sharing between non-GSO FSS and networks of the GSO FSS, recommends 1 that representative technical characteristics of existing and planned satellite systems be compiled in an electronic databank available from the Radiocommunication Bureau (BR) for the purpose of conducting sharing studies in Rad
7、iocommunication Study Groups. Details of the tables in the databank are contained in Annex 1, as pro forma to be used for the submission of technical characteristics (see Notes 1 and 2). Information on validation of the data, and descriptions of the parameters requested are given in Annexes 2 and 3;
8、 2 that, in the planning and development of new FSS networks, both GSO and non-GSO, and feeder links for MSS systems affecting the FSS allocations, the representative technical characteristics of existing and planned satellite systems in the databank be taken into consideration; 2 Rec. UIT-R S.1328-
9、4 3 that, in studies pertaining to the development of sharing criteria between satellite systems, the representative technical characteristics of existing and planned systems in the databank may be used in interference analyses; 4 that administrations planning modifications to these systems or propo
10、sing future satellite system networks in FSS bands are urged to submit their representative technical characteristics to the ITU-R using the pro forma in Annex 1 to update this databank (see also Annexes 2 and 3 and Notes 3, 4, 5 and 6). NOTE 1 The data in the databank are to be regarded as represen
11、tative examples of system technical characteristics, to be used only for sharing studies within Radiocommunication Study Groups and not as a basis for coordination between satellite networks. The databank should not be interpreted as a comprehensive source of data on the number of satellite systems
12、or their particular characteristics, and is thus not suitable for statistical studies or evaluations. NOTE 2 Additional information (textual and/or graphical) which cannot readily be incorporated into the spreadsheet format may be appended as a text file. NOTE 3 The existing information annexed hith
13、erto to this Recommendation will be held by BR until one year after approval of this revision to the Recommendation. Administrations are requested to resubmit existing technical characteristics using the pro forma in Annex 1. NOTE 4 Only data submitted in response to this Recommendation shall be inc
14、luded in the databank. NOTE 5 In order to ensure rapid and error-free incorporation into the databank, administrations are strongly encouraged to submit data in electronic format (preferably Microsoft EXCEL). NOTE 6 An explanation of the requested fields in the databank is included in Annex 2 of thi
15、s Recommendation, while Annex 3 gives an explanation of a simple check on the validity of the input data which is included in the spreadsheets. This validity check is not intended as a filter to eliminate data from the databank, but serves only to minimize the risk of inaccurate entry of the data. A
16、NNEX 1 Tables for submission of satellite system characteristics This Annex includes pro forma tables for the submission of new and revised data for the electronic databank of satellite system characteristics. Data should be submitted to the BR for consideration by Working Party 4A on paper and addi
17、tionally in spreadsheet format using these tables, blank copies of which can be downloaded from the Working Party 4A web pages at: www.itu.int/ITU-R/study-groups/sg/sg4/info/index.html Rec. UIT-R S.1328-4 3 Additional supporting information which cannot readily be incorporated into the spreadsheet m
18、ay be appended in the form of a text file, to be associated with the spreadsheet, and clearly referenced therein. TABLE 1 Representative characteristics of GSO satellite systems 1 GSO SYSTEMS UNITSExample (a) Example (b) Add as many columns as required 2 1 SYSTEM 3 1.1 Information provider Xxland Yy
19、land 4 1.2 Space station name in ITU filing XX-1 YY-4 5 1.3 Carrier designation LDR-1 SCPC 6 2 SATELLITE PARAMETERS 7 2.1 Orbital position deg. East 201 158 8 2.2 Type of transponder (Transp-transparent; Remod-remodulating) Remod Transp 9 3 CARRIER PARAMETERS 10 3.1 Uplink type (i.e. maximum, minimu
20、m or typical e.i.r.p. and C/I levels) See Note Typical Typical 11 3.2 Downlink type (i.e. maximum, minimum or typical e.i.r.p. and C/I levels) See Note Minimum Typical 12 3.3 Centre frequency of uplink band GHz 29.75 28.4 13 3.4 Uplink polarization (RHC, LHC, VL, HL or offset linear) RHC RHC (RR No.
21、 1.145) 14 3.5 Centre frequency of downlink band GHz 19.95 18.6 15 3.6 Downlink polarization (RHC, LHC, VL, HL or offset linear) LHC RHC (RR No. 1.145) 16 3.7 Access type (end-to-end if transparent transponder, on downlink if remodulating transponder) TDM FDMA 17 3.8 Uplink access type for carriers
22、using remodulating transponders TDMA N/A 18 3.9 Modulation type (e.g. FM, BPSK, QPSK etc.) (end-to-end if transparent transponder, on downlink if remodulating transponder) QPSK QPSK 19 3.10 Uplink modulation type for carriers using remodulating transponders QPSK N/A 20 3.11 Uplink occupied bandwidth
23、 per carrier MHz 1.7 0.034 21 3.12 Downlink occupied bandwidth per carrier MHz 81 0.034 4 Rec. UIT-R S.1328-4 22 4 SPACE STATION PARAMETERS 23 4.1 Peak receive antenna gain dBi 47 43.8 24 4.2 Receive antenna gain in the direction of the transmit earth station dBi 45.7 42.7 25 4.3 Receive antenna gai
24、n pattern (e.g. Rec. ITU-R S.672, CR/58 data file, etc.) S.672 Ls=20 dB Shaped 26 4.4 Satellite receive noise temperature K 700 1202 27 4.5 Transmit e.i.r.p. per carrier in the direction of the receive earth station dBW 57 15.8 28 4.6 Peak transmit antenna gain dBi 50.5 38.8 29 4.7 Transmit antenna
25、gain in the direction of the receive earth station dBi 49 38.8 30 4.8 Transmit antenna gain pattern (e.g. Rec. ITU-R S.672, CR/58 data file, etc.) S.672 Ls=20 dB Shaped 31 4.9 Transmission gain of transparent transponder link, as defined in RR App. 8 dB N/A 8.9 32 4.10 Automatic level control range
26、of transponder (0 if none) dB 0 0 33 5 EARTH STATION PARAMETERS 34 5.1 On-axis e.i.r.p. per carrier from transmit earth station dBW 41.9 38.8 35 5.2 Peak transmit antenna gain dBi 48 64.6 36 5.3 Transmit antenna gain pattern (e.g. Rec. ITU-R S.465, Rec. ITU-R S.580, etc.) S.580 S.580 37 5.4 Uplink p
27、ower control range (0, 0 dB if none) dB 12 10 38 5.5 Power control step-size (if power control used) dB 0.1 0, 0 dB if none) dB 12 10 67 5.6 Power control step size (if power control used) dB 0.1 0) of uplink power control, if used; 0 if not used. 5.5 Power control step size The size of steps in the
28、 range of power control, if uplink power control is used. 5.6 Receive antenna 3 dB beamwidth The half-power beamwidth of the earth station receive antenna. 5.7 Peak receive antenna gain The highest value of the receive antenna gain towards the space station. 5.8 Receive antenna gain pattern A descri
29、ption of the antenna radiation pattern of the earth station receive antenna (e.g. Rec. ITU-R S.465, Rec. ITU-R S.580, etc.). 5.9 Noise temperature of receive earth station The thermal noise contribution from the earth station modelled as a noise source injected at the input of the low noise amplifie
30、r. 5.10 Elevation angle of transmit earth station towards the satellite The elevation angle of the transmit antenna in the direction of the satellite. 5.11 Elevation angle of receive earth station towards the satellite The elevation angle of the receive antenna in the direction of the satellite. 6 I
31、NTERFERENCE PARAMETERS 6.1 Uplink C/I from internal sources The total carrier-to-interference ratio on the uplink from all internal sources, e.g. from intermodulation products, cross-polarization, multi-beam frequency reuse schemes, etc. 14 Rec. UIT-R S.1328-4 6.2 Uplink C/I from external sources Th
32、e total carrier-to-interference ratio on the uplink from all external sources, e.g. from terrestrial sources and other satellites. 6.3 Downlink C/I from internal sources The total carrier-to-interference ratio on the downlink from all internal sources, e.g. from intermodulation products, cross-polar
33、ization, multi-beam frequency reuse schemes, etc. 6.4 Downlink C/I from external sources The total carrier-to-interference ratio on the downlink from all external sources, e.g. from terrestrial sources and other satellites. 7 NETWORK PERFORMANCE REQUIREMENTS 7(a) Transparent or remodulating transpon
34、der Performance at input to demodulator in receive earth station 7.1 Long-term (clear-sky) C/(N+I) ratio The long-term carrier-to-noise-plus-interference ratio, as defined for clear sky propagation conditions, end-to-end for transparent transponders, on the downlink for remodulating transponders. 7.
35、2 Short-term C/(N+I) ratio The unavailability threshold, in terms of short-term carrier-to-noise-plus-interference ratio, end-to-end for transparent transponders, on the downlink for remodulating transponders. 7.3 Percentage of time for which short-term C/(N+I) should be exceeded The short-term perf
36、ormance requirement for the unavailability threshold. 7.4 C/(N+I) at which loss of demodulator synchronization occurs The carrier-to-noise-plus-interference ratio at which the demodulator will lose synchronization. 7(b) Remodulating transponder only Performance at input to demodulator in satellite r
37、eceiver 7.5 Long-term (clear-sky) C/(N+I) ratio The long-term carrier-to-noise-plus-interference ratio, as defined for clear sky propagation conditions, on the uplink for remodulating transponders. 7.6 Short-term C/(N+I) ratio The unavailability threshold, in terms of short-term carrier-to-noise-plu
38、s-interference ratio, on the uplink for remodulating transponders. 7.7 Percentage of time for which short-term C/(N+I) should be exceeded The short-term performance requirement for the unavailability threshold. 7.8 Curve linking C/N to BER Insert equation or attach curve in graphical format. 8 ADDIT
39、IONAL NOTES Additional notes may be attached, which will be appended to a text file which accompanies the databank. Examples of what might be included are details of satellite beams, spot beam coverages, additional information on radiation beam patterns, etc. Rec. UIT-R S.1328-4 15 Non-GSO system pa
40、rameters of Table 2 1 SYSTEM 1.1 Information provider The name of the administration or Sector Member that submitted the data to update the content of the data bank. 1.2 Space station name in ITU filing The name by which the space station is identified. 1.3 Carrier designation A designator produced
41、by the contributor of the data which uniquely identifies the links submitted. 2 SATELLITE PARAMETERS 2.1 Shape of orbit State whether orbit is circular or elliptical. 2.2 Orbit radius (circular orbit) or semi-major axis (elliptical orbit) The radius of circular orbits or the semi-major axis for elli
42、ptical orbits. 2.3 Inclination angle The angle of inclination between the plane of the orbit and the reference plane, generally the equatorial plane. 2.4 Eccentricity for elliptical orbits The ratio of the distance between the foci of the ellipse and the length of the major axis. 2.5 Argument of per
43、igee for elliptical orbits The angle, measured at the Earths centre, from the ascending node to perigee. 2.6 If repeating ground track, repeat period The time taken for the ground track to be repeated. 2.7 Do all satellites follow the same ground track? Yes or no. 2.8 Number of orbit planes The numb
44、er of planes in the constellation. 2.9 Number of satellites per plane The number of satellites in each plane of the constellation. 2.10 Longitude of ascending node of first plane The angle between the ascending node (i.e. the point at which the northbound satellite crosses the equator) and the Green
45、wich meridian, for repeating ground tracks only. 2.11 True anomaly of first satellite in first plane The angular distance of a satellite, within its orbit plane, from its perigee as seen from the centre of the Earth. For circular orbits, the ascending node may be substituted for perigee. 2.12 Separa
46、tion between adjacent satellites in each plane The angular separation between satellites in each plane of the constellation. 2.13 Satellite phasing between planes The angle between satellites in adjacent planes. 3 CARRIER PARAMETERS 3.1 Centre frequency of uplink band The uplink frequency in which t
47、he link might be deployed (GHz). 16 Rec. UIT-R S.1328-4 3.2 Uplink polarization The polarization of the uplink, e.g. RHC, LHC, VL, HL or offset linear. 3.3 Centre frequency of downlink band The downlink frequency in which the link might be deployed (GHz). 3.4 Downlink polarization The polarization o
48、f the downlink, e.g. RHC, LHC, VL, HL or offset linear. 3.5 Access type The method by which different users share satellite resources. This is usually done by sharing the usage of the transponder either in time (TDMA), frequency (FDMA) or by code (CDMA). Enter end-to-end access type if transparent t
49、ransponder, on downlink if remodulating transponder. 3.6 Uplink access type for carriers using remodulating transponders The method by which different users share satellite resources. This is usually done by sharing the usage of the transponder either in time (TDMA), frequency (FDMA) or by code (CDMA). Enter end-to-end access type if transparent transponder, on uplink if remodulating transponder. 3.7 Modulation type The method by which the baseband signal is converted to RF (e.g. FM, BPSK,
