1、 Recommendation ITU-R M.1905(01/2012)Characteristics and protection criteria forreceiving earth stations in theradionavigation-satellite service(space-to-Earth) operating in theband 1 164-1 215 MHzM SeriesMobile, radiodetermination, amateurand related satellite servicesii Rec. ITU-R M.1905 Foreword
2、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 limit of frequency range on the basis of which Recommendations
3、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 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 Pat
5、ent 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 Bro
6、adcasting 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 sharin
7、g 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 Resolut
8、ion ITU-R 1. Electronic Publication Geneva, 2012 ITU 2012 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without written permission of ITU. Rec. ITU-R M.1905 1 RECOMMENDATION ITU-R M.1905 Characteristics and protection criteria for receiving earth statio
9、ns in the radionavigation-satellite service (space-to-Earth) operating in the band 1 164-1 215 MHz (Questions ITU-R 217-2/4 and ITU-R 288/4) (2012) Scope Characteristics and protection criteria for radionavigation-satellite service (RNSS) receiving earth stations operating in the band 1 164-1 215 MH
10、z are presented in this Recommendation. This information is intended for performing analyses of radio-frequency interference impact on RNSS (space-to-Earth) receivers operating in the band 1 164-1 215 MHz from radio sources other than in the RNSS. The ITU Radiocommunication Assembly, considering a)
11、that systems and networks in the radionavigation-satellite service (RNSS) provide worldwide accurate information for many positioning, navigation and timing applications, including safety aspects for some frequency bands and under certain circumstances and applications; b) that there are various ope
12、rating and planned systems and networks in the RNSS; c) that characteristics of systems and networks in the RNSS and their protection criteria could be different subject to frequency bands and applications; d) that there are studies being conducted or planned on the impact to systems and networks in
13、 the RNSS from radio sources other than in the RNSS; e) that there are a large number of aeronautical and non-aeronautical RNSS applications used or planned for use in the band 1 164-1 215 MHz; f) that Recommendation ITU-R .1787 provides technical descriptions of systems and networks in the RNSS and
14、 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; g) that Recommendation ITU-R .1904 provides technical characteristics and protection criteria of receiving space stations operating in the RNSS (space-to-space) in t
15、he bands 1 164-1 215 MHz, 1 215-1 300 MHz and 1 559-1 610 MHz; h) that Recommendation ITU-R M.1901 provides guidance on this and other ITU-R Recommendations related to systems and networks in the RNSS 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
16、 and 5 010-5 030 MHz, recognizing a) that the band 1 164-1 215 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 1 164-1 215 MHz is also allocated on a primary basis to the aeronautical radionavigation service (ARNS) in all thr
17、ee Regions; 2 Rec. ITU-R M.1905 c) that No. 5.328A of the Radio Regulations (RR) states that “stations in the radionavigation-satellite service in the band 1 164-1 215 MHz shall operate in accordance with the provisions of Resolution 609 (WRC-03) and shall not claim protection from stations in the a
18、eronautical radionavigation service in the band 960-1 215 MHz. No. 5.43A of the RR does not apply. The provisions of No. 21.18 shall apply”; recommends 1 that the characteristics and protection criteria of receiving earth stations given in Annex 2 should be used in performing analyses of the interfe
19、rence impact on RNSS (space-to Earth) receivers operating in the band 1 164-1 215 MHz from radio sources other than in the RNSS; 2 that a safety margin, as discussed in Annex 1, should be applied for the protection of the safety aspects and applications of the RNSS when performing interference analy
20、ses; 3 that the following Note should be considered as part of this Recommendation. NOTE 1 The 6 dB aeronautical safety margin, as discussed in 3.2 of Annex 1, was developed for a specific aeronautical radionavigation application of the RNSS in the band 1 164-1 215 MHz, and was not intended to be ap
21、plied to non-aeronautical applications. The level of the safety margin, if any, to be applied to non-aeronautical safety applications of RNSS is to be established on the basis of further study. Annex 1 Margin for safety applications in the RNSS 1 Introduction There is a long history within ITU and t
22、he International Civil Aviation Organization (ICAO) of reserving a portion of the interference link budget for a margin in order to ensure that the safety aspects of the radionavigation service are protected. These margin values typically lie in the range of 6 to 10 dB, or more. Furthermore, there i
23、s ample precedent for a safety margin for radionavigation safety applications in ITU, for example: “Regardless of the original intentions of radio spectrum planners, there can be no doubt that the pressure on the radio spectrum for additional allocations to the various radio communication services c
24、an result in aeronautical protection criteria being effectively regarded as non-aeronautical sharing criteria. As a consequence, a safety service must take considerable precautions to ensure that any radio service sharing the same radio band is constrained sufficiently to leave an adequate margin un
25、der all likely circumstances so that the aggregate harmful interference never exceeds the required protection criteria.”1Also, Recommendation ITU-R M.1318-1 contains, in its Annex, a model for the evaluation of interference to RNSS receivers from radio sources other than in the RNSS. That model incl
26、udes the use of a factor called “protection margin (dB)”. Its description states that it is used “to ensure protection as provided by RR. No. 4.10”. 1This text appeared in Annex 5 of former Recommendation ITU-R M.1477 (Geneva, 2000). Rec. ITU-R M.1905 3 2 Purpose of safety margin A safety margin, (w
27、hich may also be called a public safety factor), is critical for safety-of-life applications in order to account for risk of loss of life due to radio-frequency interference that is real but not quantifiable. To support safety-of-life applications, all interference sources must be accounted for. 3 A
28、eronautical radionavigation applications of safety margin 3.1 Aeronautical radionavigation safety margin background The utilization of safety margins in navigation systems is well established. ICAO specifies a safety margin for the microwave landing system (MLS) of 6 dB (Annex 10 to ICAO Convention:
29、 International Standards and Recommended practices Aeronautical Telecommunications, Vol. 1 Radio Navigation Aids (Attachment G, Table G-2). The instrument landing system (ILS) applies a safety margin of 8 dB (see Recommendation ITU-R SM.1009-1, Appendix 3 to Annex 2). In each case the margin is defi
30、ned with respect to the navigation system carrier power. That is, to test system performance for these systems, the desired signal power is reduced from the nominal level by the safety margin, then tested to determine whether the system provides the required performance in the presence of interferen
31、ce. In other words, the manufacturer must design the equipment to handle the highest anticipated interference level while receiving a desired signal level lower (by the safety margin) than would be otherwise received. With global navigation satellite system (GNSS)2this approach is not feasible becau
32、se received GNSS satellite power is quite low and relatively constrained, and thus GNSS receivers operate over a limited signal dynamic range. For GNSS receivers, the principal received signal quality measure is the C/N0,EFFratio, the ratio of the recovered carrier power, C, to the effective noise +
33、 interference power spectral density, N0,EFF. GNSS receivers must be capable of operating near the minimum C/N0,EFFvalue, a region where important performance parameters, such as detected word error rate or carrier phase error, rise rapidly for small reductions in C/N0,EFFdue, for example, to interf
34、erence. 3.2 Safety margin approach for the GNSS in the band 1 164-1 215 MHz As with the MLS and ILS, the approach for the GNSS is to define a level of non-aeronautical radio-frequency interference (RFI)3that the receiver must be able to accept and still meet performance specifications. For the GNSS,
35、 the receiver RFI test limit (i.e. the design threshold) exceeds the maximum allowable environmental aggregate interference level by a safety margin. Specifically, if the aggregate continuous interference test limit for GNSS is Jagg,max(dBW) and a safety margin, M (dB), is used, then the maximum saf
36、e environmental aggregate continuous RFI, Jsafe,max(dBW) is: Jsafe,max= Jagg,max M As with the GNSS in the 1 559-1 610 MHz band (see Recommendation ITU-R M.1903, Annex 1), the necessary safety margin, M (dB), is 6 dB. 2GNSS refers to global navigation satellite system, a set of RNSS systems providin
37、g aeronautical radionavigation satellite signals as recognized by ICAO. 3Non-aeronautical interference refers to interference from sources other than the distance measuring equipment (DME), tactical air navigation system (TACAN) and equipment installed on the GNSS receiver-equipped aircraft. 4 Rec.
38、ITU-R M.1905 Annex 2 Technical characteristics and protection criteria for receiving earth stations in the RNSS (space-to-Earth) operating in the band 1 164-1 215 MHz 1 Introduction Several classes of receivers that vary in terms of function and performance are likely to use the RNSS satellite signa
39、ls in this frequency band. Table 2-1 in this Annex provides characteristics and protection criteria for several types of RNSS receivers including two types that represent air-navigation receivers. One air-navigation receiver type also uses an SBAS4signal transmitted on the same carrier centre freque
40、ncy as the RNSS signal. Other types listed include high-precision (e.g. surveying), indoor positioning, and general-purpose RNSS receivers. More details of the RNSS and SBAS signals are contained in Recommendation ITU-R M.1787. As the RNSS continues to evolve, RNSS applications using receivers that
41、have more susceptibility to RFI may come into use, requiring this Recommendation to be updated to take them into account. 2 Receiver type and application descriptions This section describes several types of current and prospective RNSS receivers. 2.1 Air-navigation receiver The air-navigation catego
42、ry represents several types of RNSS receivers. These receivers represent high integrity airborne receivers for operation in all flight phases and have specific measures to mitigate pulsed interference. Characteristics and protection criteria for two types of RNSS receivers are listed in Table 2-1. A
43、ir-navigation receiver No. 1 uses CDMA RNSS and SBAS signals5. Interference thresholds for air-navigation receiver No. 1 represent the lowest applicable limits for the set of RNSS and SBAS signals used in that receiver (see Table 2-1, column 1). Air-navigation receiver No. 2 uses FDMA RNSS signals6a
44、nd operates on several carrier frequencies simultaneously (see Table 2-1, column 2). Characteristics for the air-navigation receiver No. 2 may also apply to receivers developed for land or maritime applications that are not described in this Annex. 2.2 High-precision receiver The high-precision cate
45、gory represents RNSS receivers that are used in applications requiring high positioning accuracy (e.g. surveying, scientific, and agricultural applications). High-precision receivers use various techniques (e.g. semi-codeless techniques) to acquire and track RNSS signals 4SBAS refers to the satellit
46、e-based augmentation system, a means for providing RNSS regional measurement error correction and integrity data through a GSO satellite signal. 5The phrase “CDMA RNSS and SBAS signals” refers to the use of a technique in which all the RNSS and SBAS satellites transmit on the same carrier frequency
47、but with different modulation codes. Further signal details are contained in Annex 2 (GPS) of Recommendation ITU-R M.1787. 6The phrase “FDMA RNSS signals” refers to a technique in which all the RNSS satellites use the same modulation code but each satellite transmits on a different carrier frequency
48、. Further signal details are contained in Annex 1 (GLONASS) of Recommendation ITU-R M.1787. Rec. ITU-R M.1905 5 in two or three RNSS frequency bands for carrier phase ambiguity resolution, and require protection in all bands used. The characteristics and protection levels for high-precision receiver
49、s also apply to RNSS receivers that are designed to operate in specialized RNSS applications (e.g. single-frequency ground networks, and precision navigation). High-precision RNSS receivers and receivers designed to operate in specialized RNSS applications also can operate in stressed environments (e.g. under foliage). Two receiver types are listed in Table 2-1, column 3; each of which uses a different RNSS satellite signal type (either code division multiple access (CDMA) or frequency division multiple access (FDMA) and frequency range. The protection criteria and remaining cha
