1、 Recommendation ITU-R SM.1541-6 (08/2015) Unwanted emissions in the out-of-band domain SM Series Spectrum management ii Rec. ITU-R SM.1541-6 Foreword The role of the Radiocommunication Sector is to ensure the rational, equitable, efficient and economical use of the radio-frequency spectrum by all ra
2、diocommunication 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 a
3、nd Radiocommunication 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 licen
4、sing declarations 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
5、 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 Broadcasting service (sound) BT Broadcasting service (television) F Fixed service M Mobile, radiodetermination, amateur and related satellite services P
6、Radiowave 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
7、 standards 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, 2015 ITU 2015 All rights reserved. No part of this publication may be reproduced, by any means whatsoever,
8、 without written permission of ITU. Rec. ITU-R SM.1541-6 1 RECOMMENDATION ITU-R SM.1541-6* Unwanted emissions in the out-of-band domain* (2001-2002-2006-01/2011-09/2011-2013-2015) Scope This Recommendation provides out-of-band (OoB) domain emission limits for transmitters in the frequency range of 9
9、 kHz to 300 GHz. The ITU Radiocommunication Assembly, considering a) that Recommendation ITU-R SM.329 Unwanted emissions in the spurious domain, relates to the effects, measurements and limits to be applied to unwanted emissions in the spurious domain; b) that Recommendations ITU-R SM.329 and ITU-R
10、SM.1539 provide guidance for determining the boundary between the out-of-band (OoB) and spurious domains in a transmitted radio frequency spectrum; c) that considerations of OoB domain and necessary bandwidths are included by necessity in Recommendation ITU-R SM.328 Spectra and bandwidth of emission
11、s; d) that unwanted emissions occur after a transmitter is brought into operation and can be reduced by system design; e) that OoB domain emission limits have been successfully used as national or regional regulations in areas having a high radiocommunications density; such limits are generally desi
12、gned according to specific and detailed local needs for coexistence with other systems; f) that nevertheless there is a need, for each service, for a limited number of a more broadly generic ITU-R OoB domain emission limits, generally based on an envelope of the least restrictive OoB domain emission
13、 limits described in the above considering e); g) that where frequency assignments are provided to the Radiocommunication Bureau (BR) in accordance with Appendix 4 of the Radio Regulations (RR), the necessary bandwidth of an emission with a single carrier is given by the bandwidth portion of the emi
14、ssion designator; h) that the necessary bandwidth, referred to in RR Appendix 4 is for a single carrier transmission, and may not adequately cover the case of systems with multiple carriers, recognizing that the following terms are defined in the RR. * This Recommendation should be brought to the at
15、tention of Radiocommunication Study Groups 4, 5, 6 and 7. * Although OoB emissions are generally predominant in the OoB domain, spurious emissions may also occur in the OoB domain. It is important to note that the limits in this Recommendation apply to all the unwanted emissions in the OoB domain, b
16、oth OoB emissions and spurious emissions. 2 Rec. ITU-R SM.1541-6 Unwanted emissions 1.146 unwanted emissions*: Consist of spurious emissions and out-of-band emissions. Spurious emission 1.145 spurious emission*: Emission on a frequency or frequencies which are outside the necessary bandwidth and the
17、 level of which may be reduced without affecting the corresponding transmission of information. Spurious emissions include harmonic emissions, parasitic emissions, intermodulation products and frequency conversion products, but exclude out-of-band emissions. Out-of-band emission 1.144 out-of-band em
18、ission*: Emission on a frequency or frequencies immediately outside the necessary bandwidth which results from the modulation process, but excluding spurious emissions. Occupied bandwidth 1.153 occupied bandwidth: The width of a frequency band such that, below the lower and above the upper frequency
19、 limits, the mean powers emitted are each equal to a specified percentage /2 of the total mean power of a given emission. Unless otherwise specified in an ITU-R Recommendation for the appropriate class of emission, the value of /2 should be taken as 0.5%. Necessary bandwidth 1.152 necessary bandwidt
20、h: 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. Assigned frequency band 1.147 assigned frequency band: The frequency band within which the emissi
21、on of a station is authorized; the width of the band equals the necessary bandwidth plus twice the absolute value of the frequency tolerance. Where space stations are concerned, the assigned frequency band includes twice the maximum Doppler shift that may occur in relation to any point of the Earths
22、 surface. Assigned frequency 1.148 assigned frequency: The centre of the frequency band assigned to a station. noting a) that Recommendation ITU-R SM.1540 additionally covers cases of unwanted emissions in the OoB domain falling into adjacent allocated bands; b) that the studies required by Question
23、 ITU-R 222/1, approved by Radiocommunication Assembly 2000, could have formal and substantial impact to basic definitions used in this Recommendation. It may be necessary to revise this Recommendation in the future to reflect the results of these studies, Rec. ITU-R SM.1541-6 3 recommends 1 Terminol
24、ogy and definitions that the following additional terms and definitions should be used: 1.1 Spurious domain1 (of an emission): the frequency range beyond the OoB domain in which spurious emissions generally predominate. 1.2 OoB domain1 (of an emission): the frequency range, immediately outside the n
25、ecessary bandwidth but excluding the spurious domain, in which OoB emissions generally predominate. 1.3 dBsd and dBasd dBsd: decibels relative to the maximum value of power spectral density (psd) within the necessary bandwidth. The maximum value of psd of a random signal is found by determining the
26、mean power in the reference bandwidth when that reference bandwidth is positioned in frequency such that the result is maximized. The reference bandwidth should be the same regardless of where it is centred and is as specified in 1.6. dBasd: decibels relative to the average value of psd within the n
27、ecessary bandwidth. The average value of psd of a random signal is found by computing the mean power in the reference bandwidth and averaging that result over the necessary bandwidth. The reference bandwidth is as specified in 1.6. 1.4 dBc Decibels relative to the unmodulated carrier power of the em
28、ission. In the cases which do not have a carrier, for example in some digital modulation schemes where the carrier is not accessible for measurement, the reference level equivalent to dBc is dB relative to the mean power P. 1.5 dBpp Decibels relative to the maximum value of the peak power, measured
29、with the reference bandwidth within the occupied bandwidth. The in-band peak power is expressed in the same reference bandwidth as the OoB peak power. Both the in-band and the unwanted emissions should be evaluated in terms of peak values. For radar systems, the reference bandwidth should be selecte
30、d according to Recommendation ITU-R M.1177. 1 The terms “OoB domain” and “spurious domain” have been introduced in order to remove some inconsistency now existing between, on one hand, the definition of the terms “out-of-band emission” and “spurious emission” in RR Article 1 and, on the other hand,
31、the actual use of these terms in RR Appendix 3, as revised by World Radiocommunication Conference (Istanbul, 2000) (WRC-2000). OoB and spurious limits apply, respectively, to all unwanted emissions in the OoB and spurious domains. 4 Rec. ITU-R SM.1541-6 FIGURE 1 FIGURE 2 0 dBpp reference, maximum va
32、lue of peak power 1.6 Reference bandwidth The bandwidth required for uniquely defining the OoB domain emission limits. If not explicitly given with the OoB domain emission limit, the reference bandwidth should be 1% of the necessary bandwidth. For radar systems the reference bandwidth should be sele
33、cted in line with Recommendation ITU-R M.1177. 1.7 Measurement bandwidth The bandwidth which is technically appropriate for the measurement of a specific system. In common spectrum analysers this is generally referred as the resolution bandwidth. NOTE 1 The measurement bandwidth may differ from the
34、reference bandwidth, provided the results can be converted to the required reference bandwidth. R e f e r e nc eba ndw i dt hR e f e r e nc eba ndw i dt hM e a n p ow e rdi s pl a yM e a n p ow e rdi s pl a yF r e que nc yF r e que nc yAveragevalueofpsdMaximumvalueofpsda ) M a xi m um ps d c onc e p
35、t b) A ve r a ge ps d c onc e pt0 dB s d r e f e r e n c e ( a) m axi m u m va l u e of p s d0 dB as d r e f e r e n c e ( b ) av e r age va l u e of p s dR e f e r e nc eba ndw i dt hM e a n po w e rdi s pl a yP e a k po w e r c once ptMaximumvalueofpeakpowerMaximumvalueofmeanpowerP e a k po w e rd
36、i s pl a yPeaktomeanpowerratioRec. ITU-R SM.1541-6 5 1.8 psd For the purpose of this Recommendation, psd is the mean power per reference bandwidth. 1.9 Mean power Power integrated over a specified frequency band using measurements of the psd or an equivalent method. 1.10 Adjacent channel mean power
37、Power integrated over the bandwidth of a channel adjacent to an occupied channel using measure-ments of the psd or an equivalent method. 1.11 Peak power Power measured with the peak detector using a filter the width and shape of which is sufficient to accept the signal bandwidth. 1.12 Adjacent chann
38、el peak power Peak power measured in the bandwidth of a channel adjacent to an occupied channel using a specified channel filter. 1.13 Total assigned band Sum of contiguous assigned bands of a system consistent with the RR Appendix 4 data provided to the BR and as authorized by an administration. NO
39、TE 1 For space services, when a system has multiple transponders/transmitters that operate in adjacent bands separated by a guardband, the total assigned band should include the guardbands. In such cases, the guardbands should be a small percentage of the transponder/transmitter bandwidth. 1.14 Tota
40、l assigned bandwidth The width of the total assigned band; 2 Application of definitions that, when applying this Recommendation, guidance should be taken from the following: 2.1 OoB domain emissions Any emission outside the necessary bandwidth which occurs in the frequency range separated from the a
41、ssigned frequency of the emission by less than 250% of the necessary bandwidth of the emission will generally be considered an emission in the OoB domain. However, this frequency separation may be dependent on the type of modulation, the maximum symbol rate in the case of digital modulation, the typ
42、e of transmitter, and frequency coordination factors. For example, in the case of some digital, broadband, or pulse modulated systems, the frequency separation may need to differ from the 250% factor. Transmitter non-linearities may also spread in-band signal components into the frequency band of th
43、e OoB frequency ranges described in Annex 1, 1.3. Further, transmitter oscillator sideband noise also may extend into that frequency range described in Annex 1, 1.3. Since it may not be practical to isolate these emissions their level will tend to be included during OoB power measurements. 6 Rec. IT
44、U-R SM.1541-6 2.2 Spurious domain emissions For the purpose of this Recommendation all emissions, including intermodulation products, conversion products and parasitic emissions, which fall at frequencies separated from the centre frequency of the emission by 250% or more of the necessary bandwidth
45、of the emission will generally be considered as emissions in the spurious domain. However, this frequency separation may be dependent on the type of modulation, the maximum symbol rate in the case of digital modulation, the type of transmitter, and frequency coordination factors. For example, in the
46、 case of some digital, broadband, or pulse-modulated systems, the frequency separation may need to differ from the 250% factor. For multichannel or multicarrier transmitters/transponders, where several carriers may be transmitted simultaneously from a final output amplifier or an active antenna, the
47、 centre frequency of the emission is taken to be the centre of either the assigned bandwidth of the station or of the 3 dB bandwidth of the transmitter/transponder, using the lesser of the two bandwidths. 2.3 Necessary bandwidth and OoB domain In the case of narrow-band or wideband emissions (as def
48、ined in Recommendation ITU-R SM.1539), the extent of the OoB domain should be determined by using Table 1. TABLE 1 Start and end of OoB domain Type of emission If necessary bandwidth BN is: Offset () from the centre of the necessary bandwidth for the start of the OoB domain Frequency separation betw
49、een the centre frequency and the spurious boundary Narrow-band BL (see Note 1) 0.5 BN 2.5 BL Normal BL to BU 0.5 BN 2.5 BN Wideband BU 0.5 BN BU (1.5 BN) NOTE 1 When BN BL, no attenuation of unwanted emissions is recommended at frequency separations between 0.5 BN to 0.5 BL. NOTE 2 BL and BU are given in Recommendation ITU-R SM.1539. 2.3.1 Single carrier emissions The value of necessary bandwidth that should be used for checking whether a single carrier emission complies with limits in the OoB domain should coincide with the value in the emis
