1、 Recommendation ITU-R SA.1160-3 (07/2017) Aggregate interference criteria for data transmission systems in the Earth exploration-satellite and meteorological-satellite services using satellites in the geostationary orbit SA Series Space applications and meteorology ii Rec. ITU-R SA.1160-3 Foreword T
2、he role of the Radiocommunication Sector is to ensure the rational, equitable, efficient and economical use of the radio-frequency spectrum by all radiocommunication services, including satellite services, and carry out studies without limit of frequency range on the basis of which Recommendations a
3、re adopted. The regulatory and policy functions of the Radiocommunication Sector are performed by World and Regional Radiocommunication Conferences and Radiocommunication Assemblies supported by Study Groups. Policy on Intellectual Property Right (IPR) ITU-R policy on IPR is described in the Common
4、Patent Policy for ITU-T/ITU-R/ISO/IEC referenced in Annex 1 of Resolution ITU-R 1. Forms to be used for the submission of patent statements and licensing declarations by patent holders are available from http:/www.itu.int/ITU-R/go/patents/en where the Guidelines for Implementation of the Common Pate
5、nt Policy for ITU-T/ITU-R/ISO/IEC and the ITU-R patent information database can also be found. Series of ITU-R Recommendations (Also available online at http:/www.itu.int/publ/R-REC/en) Series Title BO Satellite delivery BR Recording for production, archival and play-out; film for television BS Broa
6、dcasting service (sound) BT Broadcasting service (television) F Fixed service M Mobile, radiodetermination, amateur and related satellite services P Radiowave propagation RA Radio astronomy RS Remote sensing systems S Fixed-satellite service SA Space applications and meteorology SF Frequency sharing
7、 and coordination between fixed-satellite and fixed service systems SM Spectrum management SNG Satellite news gathering TF Time signals and frequency standards emissions V Vocabulary and related subjects Note: This ITU-R Recommendation was approved in English under the procedure detailed in Resoluti
8、on ITU-R 1. Electronic Publication Geneva, 2017 ITU 2017 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without written permission of ITU. Rec. ITU-R SA.1160-3 1 RECOMMENDATION ITU-R SA.1160-3 Aggregate interference criteria for data transmission systems
9、 in the Earth exploration-satellite and meteorological-satellite services using satellites in the geostationary orbit (Question ITU-R 141/7) (1995-1997-1999-2017) Scope The purpose of this Recommendation is to provide aggregate interference criteria for data transmission links for GSO satellites in
10、the Earth exploration-satellite and meteorological-satellite services. Keywords EESS, METSAT, GSO satellites, data transmission, interference criteria Related Recommendations and Reports Recommendations ITU-R SA.1022, ITU-R SA.1159 and ITU-R SA.1161 The ITU Radiocommunication Assembly, considering a
11、) that interference criteria are needed to ensure that systems can be designed to achieve adequate performance in the presence of interference; b) that interference criteria may be determined using the methodology described in Recommendation ITU-R SA.1022 and the performance objectives listed in Rec
12、ommendation ITU-R SA.1159; c) that interference criteria assist in the development of criteria for sharing bands among systems, including those operating in other services; d) that systems in the Earth exploration-satellite service (EESS) and meteorological-satellite (MetSat) service must specify in
13、terference thresholds at levels greater than or equal to the permissible levels; e) that the Annex presents the parameters of representative systems that provide the basis for determination of interference criteria for pertinent transmissions in the EESS and MetSat service, recommends that the inter
14、ference criteria levels specified in Table 1 should be used as the permissible aggregate levels of interfering signal power at the antenna output of stations operating in the EESS and MetSat service. 2 Rec. ITU-R SA.1160-3 TABLE 1 Interference criteria for stations in the EESS and MetSat service usi
15、ng spacecraft in the geostationary orbit Frequency band (MHz) Interfering signal power (dBW) in the reference bandwidth to be exceeded for no more than 20% of the time Interfering signal power (dBW) in the reference bandwidth to be exceeded for no more than p% of the time 1 670-1 710 space-to-Earth
16、158.0 dBW per 1 MHz 152.8 dBW per 1 MHz p 0.025 2 025-2 110 Earth-to-space 139.9 dBW per 1 MHz 136.6 dBW per 1 MHz p 0.025 25 500-27 000 space-to-Earth 144.6 dBW per 10 MHz 133.0 dBW per 10 MHz p 0.25 NOTE 1 The interfering signal powers (dBW) in the reference bandwidths are specified for reception
17、at elevation angles 3. NOTE 2 The total interfering signal power level that may be exceeded for no more than x% of the time, where x is less than 20% but greater than the specified short-term time percentage (p% of the time), may be determined by interpolation between the specified values using a lo
18、garithmic scale (base 10) for percentage of time and a linear scale for interfering signal power density (dB). NOTE 3 The interference criteria can be expressed as permissible power flux-densities into the main beam of the receive antenna by subtracting 10 log(G 2/4) from the value given in Table 1,
19、 where G is the receive antenna gain and is the wavelength. NOTE 4 Although the interference criteria are based on the systems described in the Annex, the interference criteria apply to all systems that operate in the subject frequency bands and which provide the specified service functions. Annex B
20、asis for determination of interference criteria This Annex presents the parameters used as inputs to the methodology of Recommendation ITU-R SA.1022 to determine the interference criteria for raw instrument data downlink transmissions to main reception earth stations belonging to satellite operator
21、and data dissemination to user stations. 1 Raw instrument data downlink transmissions to main reception earth stations Table 2 develops these criteria for raw instrument data downlink transmissions to main reception earth stations, in which all of the interference enters the receiving earth station
22、directly, and none is received at these stations via the satellite that originates the data. The interference criteria can be expressed as permissible power flux-densities into the main beam of the receive antenna by subtracting 10 log(G 2/4) from the values given in Table 2, where G is the receive
23、antenna gain and is the wavelength. Rec. ITU-R SA.1160-3 3 TABLE 2 Performance of raw instrument data downlink transmissions to main reception earth stations used as a basis for interference criteria of stations operating with satellites in geostationary orbit a) Frequency band 1 670-1 710 MHz Link
24、parameter Value Notes Down-link e.i.r.p. 16.1 dBW Down-link loss 190.1 dB Free-space, polarization, and antenna pointing Down-lnk G/T 24.4 dB(K1) Down-link C/N0 79.0 dB.Hz Data rate 2.6 Mbit/s Required C/N0 78.1 dB.Hz BER 1 106 2.2 dB implementation loss 1 dB modulation loss Margin 0.9 dB Long-term
25、and short-term Receive antenna gain 45.1 dBi Receiver noise density 207.9 dB(W/Hz) Interference criteria Long-term 153.9 dB(W/2.6 MHz) q 1/3 and Mmin 1.2 dB Short-term 148.7 dB(W/2.6 MHz) q 1 and Mmin 1.2 dB b) Frequency band 25.5-27.0 GHz Link parameter Value Notes Down-link e.i.r.p. 55.5 dBW Down-
26、link loss Long-term 227.9 dB Free-space, rain and atmospheric, polarization, and antenna pointing Short-term 231.3 dB 7.1 dB excess loss Down-link G/T 37.6 dB(K1) Down-link C/N0 Long-term 93.8 dB.Hz Short-term 90.4 dB.Hz Data rate 164 Mbit/s Required C/N0 88.7 dB.Hz BER 1 109 1.5 dB implementation l
27、oss 1.75 dB modulation loss Margin Long-term 5.1 dB Short-term 1.7 dB Receive antenna gain 60.6 dBi Including pointing losses Receiver noise density 205.6 dB(W/Hz) Interference criteria Long-term 144.6 dB(W/10 MHz) q 0.1 and Mmin 4.5 dB Short-term 133.0 dB(W/10 MHz) q 1 and Mmin 4.5 dB 4 Rec. ITU-R
28、SA.1160-3 2 Data dissemination to user stations Dissemination of high-resolution processed data is affected by interference received at the station via the satellite as well as by interference transmitted directly into the station in the 1 670-1 710 MHz band. The high-resolution processed data are u
29、p-linked to the satellite in the 2 025-2 110 MHz band, and relayed, along with interfering signals entering the satellite in the same band, to the Earth station receivers via fixed-gain satellite transponders. The up-link and down-link carrier-to-noise plus interference density ratios are respective
30、ly: 101000 1/TkINCINC upup and 202000 1/TkINCINC d o w nd o w n where: I01 and I02 : interference densities transmitted into the satellite and station receivers T1 and T2 : system noise temperatures of the satellite and station receivers k : Boltzmanns constant. The composite carrier-to-noise plus i
31、nterference density ratio is: 110010000 d o w nup INCIN CIN C From Recommendation ITU-R SA.1022 this can also be written: 000 NCMIN C qwhere: M : interference-free margin q : action of the interference-free margin that the interference is allowed to consume C/N0 : composite carrier-to-noise density
32、ratio given by: 110100 / o w ndup NCNCNC From the foregoing equations: d o w nupd o w nupqNCNCNCTkINCTkIM 00 02020101/1 Assume that the up-link and down-link interference are allocated so that a fraction p of the interference received at the earth station is received via the satellite, and that a fr
33、action 1 p is transmitted directly into the station. It is desirable for p to be near 1/2 in order to provide a reasonable balance in the interference allocated to the up-link and to the down-link. For a fixed-gain transponder it can be shown that: Rec. ITU-R SA.1160-3 5 upd o w nNCNCTkIp pTkI001012
34、02 /1 so that: 100101 /111 d o w nupq NC NCTkIpM Accordingly, the permissible up-link interference density becomes: 1/ /11 0 0101 qd o w nup MNC NCTkpI for M Mmn where, according to Recommendation ITU-R SA.1022, Mmin is the smallest interference-free margin for which only a fraction q of the margin
35、is consumed by the interference. Correspondingly, the permissible down-link interference density is: 1/11 00202 qupd o w n MNC NCTkpI for M Mmin Table 3 summarizes the calculation of I01 and I02 for high-resolution, assuming that p 1/2, q 1/3, and Mmin 1.2 dB for long-term interference, and that p 1
36、/2, q 1, and Mmin 1.2 dB for short-term interference. The interference criteria can be expressed as permissible power flux-densities into the main beam of the receive antenna by subtracting 10 log(G 2/4) from the values given in Table 3, where G is the receive antenna gain and is the wavelength. TAB
37、LE 3 Performance analysis used as a basis for interference criteria of high-resolution data dissemination to user stations using geostationary satellites Link parameter Value Notes Up-link e.i.r.p. 72.1 dBW Up-link loss 191.7 dB Free-space, polarization, and antenna pointing Up-link G/T 17.5 dB(K1)
38、Post-launch measurement Up-link C/N0 91.5 dB/Hz Down-link e.i.r.p. 23.8 dBW Down-link loss 190.1 dB Free-space, polarization, and antenna pointing Down-link G/T 15.2 dB(K1) Down-link C/N0 77.5 dB.Hz Composite C/N0 77.3 dB.Hz Data rate 2.11 Mbit/s Required C/N0 75.9 dB.Hz BER 1 106 1.9 dB implementat
39、ion loss Margin 1.4 dB 6 Rec. ITU-R SA.1160-3 TABLE 3 (end) Link parameter Value Notes Up-link receive antenna gain 9.5 dBi Up-link noise density 201.6 dB(W/Hz) T 500 K Up-link interference criterion (2 025-2 110 MHz) Long-term 136.7 dB(W/2.11 MHz) q 1/3 Short-term 133.4 dB(W/2.11 MHz) q 1 Down-link
40、 receive antenna gain 39.5 dBi Down-link noise density 204.3 dB(W/Hz) T 269 K Down-link interference criterion (1 670-1 710 MHz) Long-term 153.4 dB(W/2.11 MHz) q 1/3 Short-term 148.1 dB(W/2.11 MHz) q 1 3 Conclusions 3.1 Frequency band 1 670-1 710 MHz The above analyses provide two different sets of
41、interference criteria, for raw instrument data downlink transmissions to main reception Earth stations and data dissemination to user stations respectively. It is assumed that raw instrument data downlink transmissions to main reception Earth stations are the most representative systems in the band.
42、 For simplification, it is further proposed to normalise the criteria in a 1 MHz bandwidth, leading to the following values: long-term: 158.0 dBW/MHz short-term: 152.8 dBW/MHz. 3.2 Frequency band 2 025-2 110 MHz The above analysis provides a single sets of interference criteria for data disseminatio
43、n systems. For simplification, it is further proposed to normalise the criteria in a 1 MHz bandwidth, leading to the following values: long-term: 139.9 dBW/MHz short-term: 136.6 dBW/MHz 3.3 Frequency band 25.5-27 GHz The above analysis provides a single sets of interference criteria for raw instrument data downlink transmissions to main reception, representing the new generation of systems using the band 25.5-27 GHz and leading to the following values: long-term: 144.6 dBW/10 MHz short-term: 133.0 dBW/10 MHz
