1、 Recommendation ITU-R M.2082-0 (11/2015) Methodology and technical example to assist coordination of the mobile-satellite service and the radiodetermination-satellite service with the fixed service based on the power flux-density coordination trigger levels in the 2 483.5-2 500 MHz band M Series Mob
2、ile, radiodetermination, amateur and related satellite services ii Rec. ITU-R M.2082-0 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 service
3、s, and carry out studies without 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 Gr
4、oups. Policy on Intellectual Property 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
5、 http:/www.itu.int/ITU-R/go/patents/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 S
6、atellite delivery BR Recording for 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 sen
7、sing systems S Fixed-satellite service 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
8、 Note: This ITU-R Recommendation 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.2082-
9、0 1 RECOMMENDATION ITU-R M.2082-0 Methodology and technical example to assist coordination of the mobile-satellite service and the radiodetermination-satellite service with the fixed service based on the power flux-density coordination trigger levels in the 2 483.5-2 500 MHz band (2015) Scope This R
10、ecommendation provides information on coordination of the fixed service with mobile-satellite and radiodetermination-satellite service systems operating in the 2 483.5-2 500 MHz frequency band. An estimation of the level of interference that may be caused by mobile-satellite and radiodetermination-s
11、atellite service systems is included. This Recommendation examines the impact of the relaxation of the power flux-density level that triggers coordination with the fixed service that was agreed at WRC-12 under agenda item 1.18. This Recommendation may assist when performing coordination under Radio
12、Regulations No. 9.14 with administrations requesting to operate their RDSS or MSS systems at pfd levels in excess of the thresholds defined in RR Appendix 5. Keywords RDSS, MSS, FS, MS, coordination trigger Abbreviations/Glossary FDP fractional degradation of performance pfd power flux-density Relat
13、ed ITU Recommendations, Reports Recommendation ITU-R F.758-6 System parameters and considerations in the development of criteria for sharing or compatibility between digital fixed wireless systems in the fixed service and systems in other services and other sources of interference Recommendation ITU
14、-R F.1108-4 Determination of the criteria to protect fixed service receivers from the emissions of space stations operating in non-geostationary orbits in shared frequency bands Recommendation ITU-R M.1143-3 System specific methodology for coordination of non-geostationary space stations (space-to-E
15、arth) operating in the mobile-satellite service with the fixed service 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
16、164-1 215 MHz, 1 215-1 300 MHz and 1 559-1 610 MHz 2 Rec. ITU-R M.2082-0 The ITU Radiocommunication Assembly, considering a) that the band 2 483.5-2 500 MHz is allocated to the mobile-satellite service (MSS), the radiodetermination-satellite service (RDSS), the fixed service (FS) and the mobile serv
17、ice (MS) on a worldwide co-primary basis; b) that the use of this band for the MSS is for downlink (space-to-Earth) transmissions to user terminals; c) that the necessity to coordinate space systems with administrations using the FS is determined through the use of appropriate power flux-density (pf
18、d) values given in RR Appendix 5; d) that the pfd is one of the technical parameters used for the determination of criteria which facilitate sharing between the MSS and terrestrial services; e) that FS networks use digital modulation techniques, noting a) that in the frequency band 2 483.5-2 500 MHz
19、 shared between systems in the non-geostationary MSS, and systems in the FS, Table 5-2 of RR Appendix 5 establishes the following pfd thresholds: 126 dB(W/(m2 MHz) for 0 5 126 + 0.65 ( 5) dB(W/(m2 MHz) for 5 25 113 dB(W/(m2 MHz) for 25 where is the angle of arrival (degrees) on the surface of the Ea
20、rth of the radio-frequency wave; b) that for the countries in Region 2, 43 countries in Region 1, in Australia and in Israel, in the frequency band 2 483.5-2 500 MHz shared between systems in the non-geostationary MSS and systems in the FS, Note 9 to Table 5-2 of RR Appendix 5 establishes the follow
21、ing pfd thresholds: 124.5 dB(W/(m2 MHz) for 0 5 124.5 + 0.65 ( 5) dB(W/(m2 MHz) for 5 25 111.5 dB(W/(m2 MHz) for 25 c) that in the frequency band 2 483.5-2 500 MHz shared between systems in the non-geostationary RDSS, and systems in the FS, Table 5-2 of RR Appendix 5 establishes the following pfd th
22、reshold: 129 dB(W/(m2 MHz) for 0 90 d) that for the countries in Region 2, 43 countries in Region 1, in Australia and in Israel, in the frequency band 2 483.5-2 500 MHz, shared between systems in the non-geostationary RDSS and systems in the FS, Note 9 to Table 5-2 of RR Appendix 5 establishes the f
23、ollowing pfd threshold: 128 dB(W/(m2 MHz) for 0 90 e) that the above values relate to the pfd and angles of arrival which would be obtained under free-space propagation conditions; f) that, in Region 1, the provisions of RR No. 5.398A shall be taken into account, Rec. ITU-R M.2082-0 3 recommends 1 t
24、hat, subject to mutual agreement between administrations concerned, the methodology presented in Annex 1 may be used for coordination between FS and MSS and RDSS systems as a means for determining the impact on FS systems when the threshold pfd levels contained in Table 5-2 of RR Appendix 5 are exce
25、eded; 2 that any ambiguity in specific parameters of the methodology contained in Annex 1 should be resolved through mutual agreement. NOTE Annex 2 provides a technical example of application of the methodology contained in Annex 1. Annex 1 Determining the fractional degradation of performance of fi
26、xed service systems due to power flux-density coordination trigger levels in the 2 483.5-2 500 MHz band 1 Scope The methodology described in this Annex draws on existing ITU-R Recommendations and references a general methodology for computing the aggregate interference from RDSS and MSS spacecraft a
27、s seen by a terrestrial station in the FS. Examples of the aggregate level of interference to the FS from the HIBLEO-X/HIBLEO-4 MSS and Galileo RDSS constellations are provided in the Attachment to Annex 2. 2 Methodology1 The methodology used in Recommendation ITU-R F.1108, for digital radio relay s
28、ystems, is used along with Recommendation ITU-R M.1143. Recommendation ITU-R F.1108 uses the concept of fractional degradation of performance (FDP) for digital FS stations. The FDP is the fractional increase in the percentage of time that the controlling performance criterion will not be met because
29、 of the presence of interference. It has been suggested in Recommendation ITU-R F.758-6 that an FDP of 25% is suitable for systems operating in the 2 483.5-2 500 MHz frequency range. The program simulates the interference into the FS network from the non-GSO satellite constellation(s) as follows. 2.
30、1 Calculation loop The program calculates the position and velocity vectors of the satellites of the non-GSO satellite system and stations of FS system at each time instance. At each time sample the program calculates the total interfering power at each fixed service (FS) station from all active spo
31、ts from all visible and appropriately selected MSS and RDSS satellites. If the FS receiver bandwidth does not completely overlap the MSS or RDSS signal the interfering 1 This text is adapted from Recommendation ITU-R M.1143. 4 Rec. ITU-R M.2082-0 power is then scaled by the bandwidth factor. In the
32、digital case, this interfering power is scaled to 1 MHz. The aggregate interference power from all active spot beams of all visible satellites visible to the FS station is determined using the following equation: = =1=13()4()1 1where: I : interference power (W) i : 1 of N satellites being considered
33、 in the interference calculation for the FS station j : 1 of S active spot beams on the visible selected MSS (or RDSS) satellite with frequency overlap to the current FS station receiver, taking account of the satellite spot beam frequency reuse pattern Eij : maximum e.i.r.p. density per reference b
34、andwidth input to the antenna for the jth active spot beam in its boresight direction of the ith visible selected satellite (W/reference bandwidth) Bij : reference bandwidth for the interfering signal from the jth active spot beam of the ith visible selected satellite (kHz) G 3(ij ) : antenna discri
35、mination of the jth active spot beam of the ith visible selected satellite towards the FS station ij : angle between the boresight pointing vector jth active spot beam of the ith visible selected satellite to the FS station (degrees) Li : free space loss at the given reference frequency from the ith
36、 visible selected satellite to the FS station G 4(i ): the FS stations antenna gain in the direction of the ith visible selected satellite ik : angle between the FS stations antenna pointing vector and the range vector from the FS station and the ith visible selected satellite (degrees) Bw : receive
37、r bandwidth of the affected FS station (1 MHz) F : feed loss for the FS station Pij : polarization advantage factor between jth spot beam of the ith MSS (or RDSS) satellite and the FS station. The polarization advantage Pij is to be used only if the ith MSS (or RDSS) satellite is within the 3 dB bea
38、mwidth of the FS station antenna and the FS station is within the 3 dB beamwidth of the jth spot beam of the ith MSS (or RDSS) satellite. Pij can be calculated according to the formula of Note 7 of Recommendation ITU-R F.1245. 2.2 Size and number of steps in the calculation loop It is necessary to h
39、ave enough samples at appropriate time intervals to have accurate results, taking into account all the interference received at the receiver of the fixed station. Rec. ITU-R M.2082-0 5 2.2.1 Time increment The following formulae are used, and the derivation of the formulae is fully detailed in RR Ap
40、pendix 4. As the satellite speed is about the same at the equator and at higher latitudes, the calculation of simulation time step t is made for a satellite at the equator taking into account the Earths rotation, satellite inclination and FS station antenna elevation. The worst azimuth for FDP or th
41、e azimuth of horizontal movement is not used in calculation of t. where: : satellite angular velocity in Earth fixed coordinates (geocentric geosynchronous reference coordinate system) s : satellite angular velocity in space fixed coordinates (geocentric heliosynchronous reference coordinate system)
42、 e : Earth rotation angular velocity at the equator I : satellite orbit inclination : geocentric angle between FS station and satellite R : Earth radius h : satellite altitude : FS antenna elevation angle 3dB : FS station 3 dB beamwidth Nhits : number of hits in FS station 3 dB beamwidth t : simulat
43、ion time step. 2.3 Applicable interference criteria Digital FS system For the digital FS case the program calculates the FDP for the digital station as in Annex 3 of Recommendation ITU-R F.1108: where: I : interference power in FS receiver bandwidth Bw fi : the fractional period of time that the int
44、erference power equals I NT : station receiving system noise power level. NT = k T Bw ( c o s ) ( s i n )s e sI I2 2 arc cos cos RR h t N h its 3 dB sinc o sF D P I fNi iTI m inm a xi 6 Rec. ITU-R M.2082-0 where: k : Boltzmanns constant T : FS station equivalent receiving system noise temperature (K
45、) Bw : FS receiver bandwidth (usually FDP is calculated in a 1 MHz reference bandwidth). In order to assess if coordination is triggered or not with respect to digital FS systems, the computed FDP is compared with respect to the applicable criterion of 25%. Annex 2 Technical example interference ana
46、lyses 1 Characteristics of MSS, RDSS and FS systems 1.1 Characteristics of MSS systems in the band 2 483.5-2 500 MHz For the non-GSO MSS system considered in the analyses, the characteristics shown in Table 1 have been used. TABLE 1 Typical mobile-satellite service system parameters System name HIBL
47、EO-4/HIBLEO-X Altitude 1 414 km Inclination 52 degrees Number of orbital planes 8 Number of satellites per plane 6 spaced every 60 degrees Phasing* 7.5 degrees Antenna type Multi-beam Average gain 15.0 dBi Average 3 dB beamwidth 25.3 degrees Polarization Left hand circular Signal bandwidth 13 1.23 M
48、Hz = 16.5 MHz Signal centre frequency 2 491.75 MHz User terminal receiver noise temperature 300 K User terminal receiver antenna gain 2.7 dBi User terminal receiver antenna beamwidth 126 degrees * The initial phase angle (i) of the i-th satellite in its orbital plane at reference time t = 0, measure
49、d from the point of the ascending node (0 i 360). Rec. ITU-R M.2082-0 7 1.2 Assumed RDSS system characteristics It has been noted that the Galileo system intends to provide an RDSS application with its constellation. However, no firm set of specifications has yet been published for this application. To enable computer simulations, it has been assumed that the Galileo
