1、 Recommendation ITU-R SA.509-3(12/2013)Space research earth station and radio astronomy reference antenna radiation pattern for use in interference calculations, including coordination procedures, for frequencies less than 30 GHzSA SeriesSpace applications and meteorologyii Rec. ITU-R SA.509-3 Forew
2、ord 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 Recommendati
3、ons 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 Co
4、mmon 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
5、 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 for production, archival and play-out; film for television BS
6、 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 service SA Space applications and meteorology SF Frequency sh
7、aring 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 Res
8、olution ITU-R 1. Electronic Publication Geneva, 2014 ITU 2014 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without written permission of ITU. Rec. ITU-R SA.509-3 1 RECOMMENDATION ITU-R SA.509-3 Space research earth station and radio astronomy reference
9、 antenna radiation pattern for use in interference calculations, including coordination procedures, for frequencies less than 30 GHz (1978-1990-1998-2013) Scope This Recommendation gives reference antenna radiation patterns for space research and radio astronomy services for calculating interference
10、 from a single source or from multiple sources for frequencies less than 30 GHz. The ITU Radiocommunication Assembly, considering a) that the application of coordination procedures between space research earth stations or radio astronomy observatories and stations of other services is dependent upon
11、 specific antenna radiation patterns; b) that where this information does not exist, it may be desirable to use a reference antenna radiation pattern which represents the side-lobe gain levels that are not expected to be exceeded at most off-axis angles in the majority of antennas used in the servic
12、e; c) that measured data from some large (D/ 100) parabolic Cassegrain antennas used in the Space Research Service indicate an off-axis discrimination that is as good as, or better than, that of the reference antenna radiation pattern; d) that, in the case of aggregate interference from multiple int
13、erferers, using the peak envelope radiation pattern could overestimate the interference, recommends 1 that in the absence of measured data on the levels of main-lobe or side-lobe response of a space research earth station or radio astronomy antenna which is subject to interference analyses or coordi
14、nation procedures, the following reference antenna radiation patterns be used only for large parabolic antennas with D/ 100 and for frequencies between about 1 and 30 GHz: 1.1 in cases of a single entry interference, to predict the worst-case interference from this source, the following reference an
15、tenna radiation pattern (see Fig. 1) be used: null() =nullnullnullnullnullnullnullnullnull 3( null)null: 0nullnullnull17 : nullnull32 25log : null4810 : 48 805 : 80 12010 : 120 1802 Rec. ITU-R SA.509-3 where: G(): gain (dBi) relative to an isotropic antenna : off-axis angle (degrees) G0: maximum bor
16、esight gain of the antenna (dBi) 0: of the 3-dB beamwidth of the antenna (degrees) null= nullnull17 3 (degrees) null= 10(nullnullnullnullnull)/nullnull(degrees); 1.2 in cases of multiple entry interference, to predict the aggregate interference from these multiple sources, the following reference an
17、tenna radiation pattern (see Fig. 2) be used: null() = nullnullnullnullnullnullnull 3( null)null:0nullnullnull20 : nullnull29 25log : null4813 : 48 808 : 80 12013 : 120 180where: G(): gain (dBi) relative to an isotropic antenna : off-axis angle (degrees) G0: maximum boresight gain of the antenna (dB
18、i) 0: of the 3-dB beamwidth of the antenna (degrees) null= nullnull20 3 (degrees) null= 10(nullnullnullnullnull)/nullnull(degrees); 1.3 if the actual G0and 0parameters are not available, then the following equations be used to estimate them: nullnull=10lognullnullnullnullnullnull (dBi) null=203null/
19、(degrees) where: : aperture efficiency of the antenna D: antenna diameter (m) : wavelength (m); 2 that administrations be invited to submit measured antenna radiation patterns (see Annex) which may be used, if necessary, to revise the reference antenna radiation patterns of recommends 1. Rec. ITU-R
20、SA.509-3 3 FIGURE 1 Reference antenna radiation pattern to be used in the absence of measured data (single entry interference) SA.0509-0132 25 log 1801208048101102105, Off-axis angle (degrees) 100G017G0Antenna gain (dBi)FIGURE 2 Reference antenna radiation pattern to be used in the absence of measur
21、ed data (multiple entry interference) SA.0509-0229 25 log 1801208048101102138, Off-axis angle (degrees) 100G020G0Antenna gain (dBi)4 Rec. ITU-R SA.509-3 Annex Measured radiation patterns of space research earth station and radio astronomy antennas 1 Lovell Mk1A radio astronomy antenna Figure A.1 bel
22、ow shows the measured gain of the Lovell Mk1A radio astronomy antenna at 1 420 MHz. This antenna has a single reflector of circular aperture and a diameter of 76.2 m. The peak in the measured response at around 95 is due to spillover. FIGURE A.1 Measured side-lobe pattern at 1 420 MHz SA.0509-A1Off-axis angle (degrees)Gain relativetomain beam(dB)Recommendation ITU-RSA.5090 20406080101200 20 40 60 80 1000 dBi 10 30 50 70 90
