1、 Recommendation ITU-R SM.329-12(09/2012)Unwanted emissions in the spurious domainSM SeriesSpectrum managementii Rec. ITU-R SM.329-12 Foreword The role of the Radiocommunication Sector is to ensure the rational, equitable, efficient and economical use of the radio-frequency spectrum by all radiocommu
2、nication services, including satellite services, 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 Radio
3、communication Assemblies supported by Study Groups. 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 dec
4、larations by patent holders are available from 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
5、:/www.itu.int/publ/R-REC/en) Series Title BO Satellite 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 Radiowav
6、e propagation RA Radio astronomy RS Remote sensing 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 standar
7、ds emissions V Vocabulary and related subjects Note: This ITU-R Recommendation was approved in English under the procedure detailed in Resolution 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
8、 written permission of ITU. Rec. ITU-R SM.329-12 1 RECOMMENDATION ITU-R SM.329-12 Unwanted emissions in the spurious domain*(1951-1953-1956-1959-1963-1966-1970-1978-1982-1986-1990-1997-2000-2001-2003-2011-2012) Scope This Recommendation provides limits for unwanted emissions in the spurious domain,
9、as well as measurement methods of spurious domain emissions. The ITU Radiocommunication Assembly, considering a) that Recommendation ITU-R SM.328 gives definitions and explanatory notes which should be used when dealing with bandwidth, channel spacing and interference scenarios; when distinguishing
10、between out-of-band emissions and spurious emissions; and when specifying limits for out-of-band domain emissions; b) that a difficulty faced in applying the limits for unwanted emissions in the spurious domain is knowing precisely the value of the necessary bandwidth and exactly where in the spectr
11、um the limits for spurious domain should begin to apply, particularly for services using broadband or digitally-modulated emissions which may have both noise-like and discrete spurious components; c) that limitation of the maximum permitted level of spurious domain emissions1at the frequency, or fre
12、quencies, of each spurious domain emission is necessary to protect all radio services; d) that stringent limits may lead to an increase in size or in complexity of radio equipment, but will in general increase protection of other radio services from interference; e) that every effort should be made
13、to keep limits for unwanted emissions in out-of-band and spurious domains, both for existing and new services, at the lowest possible values taking account of the type and nature of the radio services involved, economic factors, and technological limitations, and the difficulty of suppressing harmon
14、ic emissions from certain high power transmitters; f) that there is a need to define the methods, units of measurements and bandwidth, and the bandwidths to be used for measurement of power at frequencies other than the centre frequency. This will encourage the use of rational, simple, and effective
15、 means of reducing unwanted emissions; g) that the relation between the power of the spurious domain emission supplied to a transmitting antenna and the field strength of the corresponding signals, at locations remote from the transmitter, may differ greatly, due to such factors as antenna character
16、istics at the frequencies of the spurious domain emissions, propagation anomalies over various paths and radiation from parts of the transmitting apparatus other than the antenna itself; *The limits in this Recommendation apply to any out-of-band or spurious emissions in the spurious domain. Spuriou
17、s emissions are generally predominant in the spurious domain. 1Spurious domain emissions are unwanted emissions at frequencies within the spurious domain. 2 Rec. ITU-R SM.329-12 h) that field-strength or pfd measurements of unwanted emissions, at locations distant from the transmitter, are recognize
18、d as the direct means of expressing the intensities of interfering signals due to such emissions; j) that in dealing with emissions on the centre frequencies, administrations customarily establish the power supplied to the antenna transmission line, and may alternatively or in addition measure the f
19、ield strength or pfd at a distance, to aid in determining when a spurious domain emission is causing interference with another authorized emission, and a similar, consistent procedure would be helpful in dealing with spurious domain emissions (see Article 15, No. 15.11 of the RR); k) that for the mo
20、st economical and efficient use of the frequency spectrum, it is necessary to establish general maximum limits of spurious domain emissions, while recognizing that specific services in certain frequency bands may need lower limits of spurious domain emissions from other services for technical and op
21、erational reasons as may be recommended in other ITU-R Recommendations (see Annex 4); l) that transmitters operating in space stations are increasingly employing spread-spectrum and other broadband modulation techniques that can produce out-of-band and spurious emissions at frequencies far removed f
22、rom the carrier frequency, and that such emissions may cause interference to passive services, including the radio astronomy service, recognizing however, that spectrum shaping techniques, which are widely used to increase the efficiency of spectral usage, result in an attenuation of side band emiss
23、ions; m) that spurious domain emission limits applicable to transmitters are a function of: the radiocommunication services involved and the minimum protection ratio determined in every frequency band; the type of environment where transmitters could be found (urban, suburban, rural, etc.); the type
24、 of transmitter; the minimum distance between the transmitter in question and the potential victim radio receiver; all possible decouplings between the antenna of the interfering transmitting antenna at the reception frequency and the receiving antenna of the radio receiver including the propagation
25、 model, polarization decoupling and other decoupling factors; the probability of occurrence of the spurious radiation of the transmitter when the receiver is active; the fact that a transmitter is active or idle, or that there are simultaneous active transmitters; n) that some space stations have ac
26、tive antennas and the measurement of power as supplied to the antenna transmission line cannot cover emissions created within the antenna. For such space stations, the determination of field strength or pfd at a distance should be established by administrations to aid in determining when an emission
27、 is likely to cause interference to other authorized services; o) that spurious domain emissions may exist in the whole radio spectrum, but practical difficulties may dictate a frequency limit above which they need not to be measured; p) that Recommendation ITU-R SM.1539 deals with variation of the
28、boundary between the out-of-band and spurious domains, Rec. ITU-R SM.329-12 3 noting a) that the studies required by the new Question ITU-R 222/1, approved by the Radiocommunication Assembly 2000, could have formal and substantial impact to basic definitions used in this Recommendation. It may be ne
29、cessary to revise this Recommendation in the future to reflect the results of these studies, recommends that the following should be used when spurious domain emission limits, and their methods of measurement, are applied: 1 Terminology and definitions The following terms and definitions complement
30、those already defined in the RR. (Definitions shown in italics are a direct quotation from the RR for completeness.) 1.1 Spurious emission (RR Article 1, No. 1.145) Emission on a frequency, or frequencies, which are outside the necessary bandwidth and the level of which may be reduced without affect
31、ing the corresponding transmission of information. Spurious emissions include harmonic emissions, parasitic emissions, intermodulation products and frequency conversion products but exclude out-of-band emissions. 1.1.1 Harmonic emissions Spurious emissions at frequencies which are whole multiples of
32、 the centre frequency emissions. 1.1.2 Parasitic emissions Spurious emissions, accidentally generated at frequencies which are independent both of the carrier or characteristic frequency of an emission and of frequencies of oscillations resulting from the generation of the carrier or characteristic
33、frequency. 1.1.3 Intermodulation products Spurious intermodulation products result from intermodulation between: the oscillations at the carrier, characteristic, or harmonic frequencies of an emission, or the oscillations resulting from the generation of the carrier or characteristic frequency; and
34、oscillations of the same nature, of one or several other emissions, originating from the same transmitting system or from other transmitters or transmitting systems. 1.1.4 Frequency conversion products Spurious emissions, not including harmonic emissions, at the frequencies, or whole multiples there
35、of, or sums and differences of multiples thereof, of any oscillations generated to produce the carrier or characteristic frequency of an emission. 1.1.5 Broadband and narrow-band emission with respect to the measurement apparatus A broadband emission is an emission which has “a bandwidth greater tha
36、n a particular measuring apparatus or receiver” (see the International Electrotechnical Vocabulary (IEV)/International Electrotechnical Commission (IEC) 161-06-11). A narrow-band emission is an emission which has “a bandwidth less than a particular measuring apparatus or receiver” (see IEV/IEC, 161-
37、06-13). 4 Rec. ITU-R SM.329-12 1.2 Out-of-band emission (RR Article 1, No. 1.144) Emission on a frequency or frequencies immediately outside the necessary bandwidth which results from the modulation process, but excluding spurious emissions. 1.3 Unwanted emissions (RR Article 1, No. 1.146) Consist o
38、f spurious emissions and out-of-band emissions. 1.3bis Out-of-band domain2(of an emission): The frequency range, immediately outside the necessary bandwidth but excluding the spurious domain, in which out-of-band emissions generally predominate. NOTE 1 Out-of-band emissions, defined based on their s
39、ource, occur in the out-of-band domain and, to a lesser extent, in the spurious domain. Spurious emissions likewise may occur in the out-of-band domain as well as in the spurious domain. 1.3ter Spurious domain2(of an emission): The frequency range beyond the out-of-band domain in which spurious emis
40、sions generally predominate. 1.4 Necessary bandwidth (RR Article 1, No. 1.152) For a given class of emission, the width of the frequency band which is just sufficient to ensure the transmission of information at the rate and with the quality required under specified conditions. For application to mu
41、lti-channel or multi-carrier transmitters/transponders, where several carriers may be transmitted simultaneously from a final output amplifier or an active antenna, the necessary bandwidth is taken to be the transmitter or transponder bandwidth, as its 3 dB bandwidth. This does not apply to base sta
42、tions in the mobile service or to fixed wireless access base stations using mobile technology. For fixed service, Recommendation ITU-R F.1191 is to be used to calculate the necessary bandwidth in the case of fixed digital radio multi-carrier systems. For the radiodetermination service, the necessary
43、 bandwidth of frequency-agile radars is taken to be the part of the allocated band over which the carrier frequencies of those radars tune. 1.5 Active state of a transmitter That state of a transmission station which produces the authorized emission. 1.6 Idle or standby state of a transmitter That s
44、tate of a transmission station where the transmitter is available for traffic but is not in active state. 2The terms “out-of-band domain” and “spurious domain” have been introduced in order to remove some inconsistency now existing between, on one hand, the definitions of the terms “out-of-band emis
45、sion” and “spurious emission” in RR Article 1 and, on the other hand, the actual use of these terms in RR Appendix 3, as revised by the World Radiocommunication Conference (Istanbul, 2000) (WRC-2000). Out-of-band domain emission and spurious domain emission limits apply, respectively, to all unwante
46、d emissions in the out-of-band and spurious domains. Rec. ITU-R SM.329-12 5 Primary radars are not considered to operate in a standby state since the transmitter is in an active state during operation. Also, pulsed radar systems are not considered to be in the standby state during their interpulse i
47、ntervals. Neither are time division communication systems to be considered to be in the idle or standby state in the interval between time slots. 2 Application of limits 2.1 The levels of spurious domain emissions could be expressed in terms of the peak envelope power or in terms of the mean power s
48、upplied by the transmitter to the antenna feeder line at the frequencies of the emission concerned, within a defined reference bandwidth, depending on the nature of the radio service of the transmitter. 2.2 Alternatively the levels of spurious domain emissions could be expressed in terms of the fiel
49、d strength or pfd on the surface of the Earth, at the frequencies of the spurious domain emission concerned. 2.3 According to the principles stated in Appendix 3 to the RR, the spurious domain generally consists of frequencies separated from the centre frequency of the emission by 250% or more of the necessary bandwidth of the emission. However, this frequency separation may be dependent on the type of modulation used, the maximum bit rate in the case of digital modulation, the type of transmitter, and frequency coordination factors. For example, in the case of some dig
