1、 Recommendation ITU-R M.2031-1 (09/2015) Characteristics and protection criteria of receiving earth stations and characteristics of transmitting space stations in the radionavigation-satellite service (space-to-Earth) operating in the band 5 010-5 030 MHz M Series Mobile, radiodetermination, amateur
2、 and related satellite services ii Rec. ITU-R M.2031-1 Foreword The 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
3、 limit of frequency range on the basis of which Recommendations are 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 Pro
4、perty Right (IPR) ITU-R policy on IPR is described in the Common 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/pate
5、nts/en where the Guidelines for Implementation of the Common Patent 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 f
6、or production, archival and play-out; film for television BS Broadcasting 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 s
7、ervice SA Space applications and meteorology SF Frequency sharing 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
8、 was approved in English under the procedure detailed in Resolution ITU-R 1. Electronic Publication Geneva, 2015 ITU 2015 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without written permission of ITU. Rec. ITU-R M.2031-1 1 RECOMMENDATION ITU-R M.2031-
9、11 Characteristics and protection criteria of receiving earth stations and characteristics of transmitting space stations in the radionavigation-satellite service (space-to-Earth) operating in the band 5 010-5 030 MHz (Questions ITU-R 217-2/4 and ITU-R 288/4) (2012-2015) Scope Characteristics and pr
10、otection criteria for radionavigation-satellite service (RNSS) receiving earth stations, and characteristics of RNSS transmitting space stations planned or operating in the band 5 010-5 030 MHz are presented in this Recommendation. This information is intended for performing sharing and compatibilit
11、y analyses of radiofrequency interference impact on systems and networks in the RNSS (space-to-Earth) operating in the band 5 010-5 030 MHz from radio sources other than in the RNSS. Keywords RNSS, protection criteria, radiofrequency interference impact Abbreviations/Glossary AWGN additive white Gau
12、ssian noise PDC pulse duty cycle PNT position, navigation and timing PRF pulse repetition frequency RHCP Right-hand circular polarization SQPN Staggered quadrature pseudo-random noise SQPSK Staggered quadrature phase-shift keying SSC Spectral separation coefficient Related ITU Recommendations, Repor
13、ts Recommendation ITU-R M.1318-1 Evaluation model for continuous interference from radio sources other than in the radionavigation-satellite service to the radionavigation-satellite service systems and networks operating in the 1 164-1 215 MHz, 1 215-1 300 MHz, 1 559-1 610 MHz and 5 010-5 030 MHz ba
14、nds Recommendation ITU-R M.1787-2 Description of systems and networks in the radionavigation-satellite service (space-to-Earth and space-to-space) and technical characteristics of transmitting space stations operating in the bands 1 164-1 215 MHz,1 215-1 300 MHz and 1 559-1 610 MHz Recommendation IT
15、U-R M.1831-1 A coordination methodology for RNSS inter-system interference estimation 1 This Recommendation should be brought to the attention of ITU-R Study Group 5 and the International Civil Aviation Organization (ICAO). 2 Rec. ITU-R M.2031-1 Recommendation ITU-R M.1901-1 Guidance on ITU-R Recomm
16、endations related to systems and networks in the radionavigation-satellite service operating in the frequency bands 1 164-1 215 MHz, 1 215-1 300 MHz, 1 559-1 610 MHz, 5 000-5 010 MHz and 5 010-5 030 MHz Recommendation ITU-R M.1902-0 Characteristics and protection criteria for receiving earth station
17、s in the radionavigation-satellite service (space-to-Earth) operating in the band 1 215-1 300 MHz Recommendation ITU-R M.1903-0 Characteristics and protection criteria for receiving earth stations in the radionavigation-satellite service (space-to-Earth) and receivers in the aeronautical radionaviga
18、tion service operating in the band 1 559-1 610 MHz Recommendation ITU-R M.1904-0 Characteristics, performance requirements and protection criteria for receiving stations of the radionavigation-satellite service (space-to-space) operating in the frequency bands 1 164-1 215 MHz, 1 215-1 300 MHz and 1
19、559-1 610 MHz Recommendation ITU-R M.1905-0 Characteristics and protection criteria for receiving earth stations in the radionavigation-satellite service (space-to-Earth) operating in the band 1 164-1 215 MHz Recommendation ITU-R M.1906-1 Characteristics and protection criteria of receiving space st
20、ations and characteristics of transmitting earth stations in the radionavigation-satellite service (Earth-to-space) operating in the band 5 000-5 010 MHz Recommendation ITU-R M.2030-0 Evaluation method for pulsed interference from relevant radio sources other than in the radionavigation-satellite se
21、rvice to the radionavigation-satellite service systems and networks operating in the 1 164-1 215 MHz, 1 215-1 300 MHz and 1 559-1 610 MHz frequency bands The ITU Radiocommunication Assembly, considering a) that systems and networks in the radionavigation-satellite service (RNSS) provide worldwide ac
22、curate information for many positioning, navigation and timing applications, including safety aspects for in some frequency bands and under certain circumstances and applications; b) that there are various operating and planned systems and networks in the RNSS; c) that studies are being conducted on
23、 the interference into RNSS systems and networks from other radio services, recognizing a) that the band 5 010-5 030 MHz is allocated on a primary basis to the RNSS (space-to-Earth and space-to-space) in all three Regions; b) that the band 5 010-5 030 MHz is also allocated on a primary basis to the
24、aeronautical radionavigation service (ARNS) in all three Regions; c) that the band 5 010-5 030 MHz is also allocated on a primary basis to the aeronautical mobile-satellite (route) service (AMS(R)S) in all three Regions subject to RR No. 9.21; Rec. ITU-R M.2031-1 3 d) that , under RR No. 5328B, “the
25、 use of the bands 1 164-1 215 MHz, 1 215-1 300 MHz, 1 559-1 610 MHz and 5 000-5 010 MHz by systems and networks in the RNSS for which complete coordination or notification information, as appropriate, is received by the Radiocommunication Bureau after 1 January 2005 is subject to the application of
26、the provisions of RR Nos. 9.12, 9.12A and 9.13 ”, and studies to determine additional methodologies and criteria to facilitate such coordination are being planned; e) that RR No. 5.443B and Resolution 741 (Rev.WRC-12) provide aggregate power flux-density limits on space stations in the RNSS to preve
27、nt harmful interference to the radio astronomy service (RAS) operating in the band 4 990-5 000 MHz; f) that RR No. 5.443B provides aggregate power flux-density limits on space stations in the RNSS to prevent harmful interference to the microwave landing system which operates in the ARNS above 5 030
28、MHz; g) that Recommendation ITU-R M.1901 provides guidance on ITU-R Recommendations related to systems and networks in the RNSS, recommends 1 that the characteristics and protection criteria of receiving earth stations and the characteristics of transmitting space stations given in Annexes 1, 2 and
29、3 should be used in performing analyses of radio frequency interference impact on systems and networks in the RNSS (space-to-Earth) operating in the band 5 010-5 030 MHz from radio sources other than in the RNSS; 2 that the allowance for interference to service links of systems and networks in the R
30、NSS (space-to-Earth) in Annexes 1 and 2 operating in the band 5 010-5 030 MHz from all radio sources other than in the RNSS, not exceed the interference threshold values given in Tables 1-1 and 2-4. Annex 1 Typical technical characteristics and protection criteria for Galileo receiving earth station
31、s operating in the band 5 010-5 030 MHz 1 Introduction The Galileo Positioning System service link provides information used to determine position, navigation and timing (PNT) by suitably equipped navigation receivers. This Annex focuses on the Galileo Positioning System service link receiving chara
32、cteristics and does not address transmitting space stations of the same network. It is anticipated that this Annex will be updated in a future revision of this Recommendation once the transmitting space station characteristics are available. 2 Galileo service link characteristics The Galileo PNT ser
33、vice provides downlinks in the 5 010-5 030 MHz band for the PNT requirements of mobile users (land, maritime, aeronautical). Galileo PNT offers two services: one with global coverage and one that makes use of spot beams, providing higher C/N0 in specific areas. To provide high ranging accuracies and
34、 positioning performances, wideband signal transmissions are essential. Similar to the RNSS signal transmissions 4 Rec. ITU-R M.2031-1 in L-band, the transmissions in C-band are implemented as spread spectrum signals with multiplexed signal components. Compared to the sharing conditions in the RNSS
35、allocations between 1 164 MHz and 1 610 MHz, the band 5 010-5 030 MHz offers significantly lower levels of potential interference that renders it attractive for safety critical and similar elevated service applications. The derived receiver protection criteria are given in Table 1-1 below, using the
36、 downlink conditions for a global coverage beam. The different signal components are multiplexed using constant envelope modulations. Full service quality, as required by market demands, has to be achieved for all elevation angles above 5. The service link assumes to provide PNT services to mobile R
37、NSS receivers from satellites visible above 5 elevation using hemispherical coverage antennas with a gain of 5 dBi. The gain for the assumed typical receive antenna varies from 5 dBi to +4 dBi for elevation angles between 5 and 90. 3 RNSS receiver protection criteria The aggregate interference thres
38、hold levels in Table 1-1 are calculated for interference of continuous transmissions only, assumed as white noise. The values of the aggregate narrow-band interference threshold levels in Table 1-1 are tentative. As outlined in Recommendation ITU-R M.1831, while there is an appropriate method to mod
39、el continuous external wideband interference scenarios, additional methods need to be defined for narrow-band and pulsed interference and at this time there is no Recommendation that handles narrow-band interference. To provide PNT information, RNSS receivers apply several critical steps in the RF r
40、eception and processing of spread-spectrum signals. These process steps are signal (carrier and phase) acquisition, carrier and phase tracking, code and sub-carrier tracking and decoding of the navigation message. The protection of the performances for the aforementioned receiver processes require t
41、herefore special attention as it is not only the degrading of the C/N0 due to interferences simplified as white noise, but also the spectral shape of these interferences that could harmfully degrade the receiver performance. In other words, coloured noise can degrade the receiver performance even in
42、 the case of a presumably harmless C/N0 degradation based on an inappropriate additive white Gaussian noise (AWGN) interference model. Coloured noise also has an influence on the implementation of early-late decorrelators, which are an essential element in the RNSS receiver process. Recommendation I
43、TU-R M.1831 describes the calculation process for coordination between RNSS systems taking the spectral signal characteristics into account by applying a Spectral Separation Coefficient (SSC). Similarly to continuous interferences, the C/N0 degradations computed with pulsed interferences and conside
44、ring the white noise assumption are not representative of the real effects onto the receiver performances. Additionally to the continuous interferences new parameters, as the peak power, the pulse duty cycle (PDC) and the pulse repetition frequency (PRF) need to be taken into account for an adequate
45、 evaluation of receiver performance degradations. Closed-form expressions can consider these additional parameters, but the limits of modelling become apparent if non-linear effects on the receiver front-end have to be taken into account. In the case of pulsed interference, the time required to tran
46、sit from a saturated receiver front-end during the pulse to a steady state, where linear equations are valid, highly depends on receiver implementations. During the time period of the pulse duration added to the previous recovery time, the samples provided to the correlator are useless for tracking
47、or data-demodulation. Rec. ITU-R M.2031-1 5 The higher the number of pulses per coherent integration interval, the larger will be the degradation for a fixed PDC, due to accumulated effects of the recovery times. The pulse duration has to be only a small portion of the coherent integration period. I
48、n general, any time period showing strongly degraded samples caused by the saturation of the receiver front-end due to high power pulses, that are greater than or equal to a tenth of the receivers coherent integration time (usually about 1 ms), could harmfully degrade the integration process. In ord
49、er to avoid repetition of the aforementioned effects it is necessary to have the PRF non-proportional to the symbol rate of the RNSS signals or any fraction of it. Mitigation strategies to protect the receiver against pulsed interference are considered to be left with receiver designers and manufacturers as a competitive asset rather than a limiting constraint imposed by Radio Regulations. TABLE 1-1 Service link characteristics and protection criteria for Galileo receiving earth stations operating in the band 5 010-5 030 MHz Parameter RNSS parameter description Signal frequency ran
