1、BRITISH STANDARD BS6160-4: 1981 IEC489-4: 1980 Methods of Measurement for radio equipment used in the mobile services Part4: Transmitters employing single-sideband emissions (A3A, A3H or A3J) UDC 621.396.9182.3:621.317:621.396.61 * A3A, A3H, A3JBS6160-4:1981 This BritishStandard, having been prepare
2、d under the directionof the Electronic Equipment Standards Committee,was published underthe authority oftheExecutive Board and comes into effect on 30October1981 BSI04-2000 The following BSI references relate to the work on this standard: Committee referenceEEL/25 Draft for comment80/28654DC ISBN 0
3、580 12315 4 Cooperating organizations The Electronic Equipment Standards Committee, under whose direction this BritishStandard was prepared, consists of representatives from the following: British Electrical and Allied Manufacturers Association (BEAMA) British Radio Equipment Manufacturers Associati
4、on* Cable and Wireless Limited Cable Television Association of Great Britain Department of Industry (National Physical Laboratory) Electrical, Electronic, Telecommunications and Plumbing Union Electricity Supply Industry in England and Wales Electronic Components Industry Federation Electronic Engin
5、eering Association* Institution of Electronic and Radio Engineers* Oil Companies Materials Association Post Office* Post Office Engineering Union Scientific Instrument Manufacturers Association The organizations marked with an asterisk in the above list, together with the following, were directly re
6、presented on the Technical Committee entrusted with the preparation of this BritishStandard: British Broadcasting Corporation Home Office Independent Broadcasting Authority Ministry of Defence Radio, Electrical and Television Retailers Association Radio Society of Great Britain Amendments issued sin
7、ce publication Amd. No. Date of issue CommentsBS6160-4:1981 BSI 04-2000 i Contents Page Cooperating organizations Inside front cover National foreword ii Section 1. Supplementary definitions and conditions of measurement 1 Scope 1 2 Object 1 3 Supplementary terms and definitions 1 4 Standard test co
8、nditions 1 5 Supplementary test conditions 2 6 Characteristics of the measuring equipment 3 Section 2. Methods of measurement 7 Frequency error 3 8 Terminal radio-frequency power 3 9 Radiated radio-frequency power 8 10 Input power and overall efficiency 15 11 Inter-transmitter intermodulation 15 12
9、Modulation characteristic 15 13 Audio-frequency harmonic distortion factor 16 14 Relative intermodulation product level 17 15 Automatic modulation control characteristic 17 16 Transmitter attack time 18 17 Transmitter performance under conditions deviating from standard test conditions 18 Appendix A
10、 Recommended characteristics of the measuring equipment 20 Appendix B Guide for construction of a radiation test site(30m) 20 Appendix C Example of a mains power line stabilization network 23 Figure 1 Input-signal measuring arrangement 2 Figure 2 Measuring arrangement for terminal spurious narrow-ba
11、ndwidth radio-frequency components 5 Figure 3 Measuring arrangement for terminal spurious transmitter noise 7 Figure 4 Arrangement for measuring out-of-band power 9 Figure 5 Measuring arrangement for radiated spurious transmitter noise 12 Figure 6 Measuring arrangement for radiated out-of-band power
12、 14 Figure 7 Arrangement for measuring transmitter characteristics 16 Figure B.1 Measuring arrangement for transmitter at30m 22 Figure C.1 Mains power line stabilization network (also known as artificial mains network) 24 Figure C.2 Vector diagram of interference voltages 25 Figure C.3 Example of a
13、mains power line stabilization network 25 Table I 24 Publications referred to Inside back coverBS6160-4:1981 ii BSI 04-2000 National foreword This BritishStandard has been prepared under the direction of the ElectronicEquipment Standards Committee. It is identical with IEC Publication489-4:1979 “Met
14、hods of measurement for radio equipment used in the mobile services. Part4: Transmitters employing single-sideband emissions (A3A, A3H or A3J)” published by the International Electrotechnical Commission (IEC). This Part should be read, where applicable, in conjunction with Part1 of this standard. NO
15、TEThe emission designations A3A, A3H and A3J used in this BritishStandard are those which were given in Article2 of the ITU 1)Radio Regulations prior to the World Administrative Radio Conference held in1979 (WARC 79). New designations for emissions were agreed at WARC 79 and will be incorporated int
16、o this BritishStandard when the changes are made to the corresponding part of IEC Publication489. Terminology and conventions. The text of the International Standard has been approved as suitable for publication as a BritishStandard without deviation. Some terminology and certain conventions are not
17、 identical with those used in BritishStandards. References to page numbers relate to IEC page numbers given in brackets at the bottom of each page. There is no corresponding BritishStandard for IEC244-6 referred to in9.7.1. The Technical Committee has reviewed the provisions of IEC244-6 and has deci
18、ded that they are acceptable for use in conjunction with this standard. There are no corresponding BritishStandards for IEC106 and C.I.S.P.R. Publications2,2A and4 but the references are for information only and therefore the validity of this standard is not affected. A British Standard does not pur
19、port to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front
20、cover, pagesi andii, pages1 to26, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. 1) International Telecommunications Union. Cross-references
21、International Standard Corresponding BritishStandard IEC489 BS6160 Methods of measurement for radio equipment used in the mobile services IEC489-1:1976 Part1:1981 General definitions and standard conditions of measurement (Identical) IEC489-5:1979 Part5:1981 Receivers employing single-sideband techn
22、iques (A3A, A3H or A3J) (Identical)BS6160-4:1981 BSI 04-2000 1 Section 1. Supplementary definitions and conditions of measurement 1 Scope This standard refers specifically to mobile radio transmitters having audio-frequency bandwidths generally not exceeding10kHz for the transmission of voice and ot
23、her types of signals, using single-sideband amplitude modulation with full, reduced or suppressed carrier. This standard is intended to be used in conjunction with IEC Publication489-1: Part 1: General Definitions and Standard Conditions of Measurement. The supplementary terms and definitions and th
24、e conditions of measurement set forth in this standard are intended for type tests and may be used also for acceptance tests. 2 Object The object of this standard is to standardize the definitions, the conditions and the methods of measurement used to ascertain the performance of transmitters within
25、 the scope of this standard and to make possible a meaningful comparison of the results of measurements made by different observers and on different equipment. 3 Supplementary terms and definitions For the purpose of this standard, the following supplementary definitions apply. 3.1 input simulation
26、network (seeFigure 1, page 2) a weighting network which modifies the characteristics of an audio-frequency generator so that it simulates the amplitude/frequency characteristics of a device which produces an electrical signal as a result of a physical change 3.2 reference sideband power the power of
27、 one necessary sideband established during the measurement of the rated radio-frequency output power (seeSub-clause8.2) 3.3 peak envelope power (P p ) the average power supplied to the transmission line by a transmitter during one radio-frequency cycle at the highest crest of the modulation envelope
28、 (ITU RR1-20,95;1976) 3.4 standard test modulations (A) and (B) standard test modulation (A) is the modulation due to a sinusoidal input-signal of1000Hz at a level to produce the reference sideband power standard test modulation (B) is the modulation due to two sinusoidal input signals of1000Hz and1
29、600Hz, each of which produces a sideband having a level equal to the reference sideband power 3.5 antenna/aerial in this standard, the term “antenna” is synonymous with “aerial” 4 Standard test conditions Unless otherwise specified, all measurements shall be performed under the general test conditio
30、ns as stated in IEC Publication489-1 and the supplementary test conditions given below. 4.1 Radiation measurements For absolute measurements, a suitable test site, equipped with radiation measurements equipment, shall be used. For relative measurements, a radiation coupling system, for example a tes
31、t fixture having stable characteristics over the range of measurement frequencies, shall be used. In this case, the output terminals of the test fixture shall be treated as the output terminals of the transmitter.BS6160-4:1981 2 BSI 04-2000 5 Supplementary test conditions 5.1 Connections to the meas
32、uring equipment Care must be taken to ensure that the measuring equipment and any coupling devices do not adversely affect the transmitter loading conditions. 5.2 Input-signal measuring arrangement for transmitters having accessible input terminals 5.2.1 Input-signal source The input-signal source s
33、hall consist of one or more audio-frequency generators connected to the transmitter input terminals as shown in Figure 1, page 2. 5.2.2 Input-signal voltage The composite voltage across terminalsa) andb) of the arrangement shown in Figure 1, expressed in terms of the individual voltages. 5.2.3 Refer
34、ence input-signal voltage The r.m.s. input voltage that produces standard test modulation (A). 5.3 Modulation limiting The modulation limiter, if present, shall be adjusted for normal operation unless otherwise specified. 5.4 Pre-emphasis Pre-emphasis networks, if included in the transmitter, shall
35、be operative unless otherwise specified. 5.5 Test load for transmitters having accessible antenna terminals A non-radiating load, with an impedance and power rating specified by the transmitter manufacturer, to replace the antenna including any associated transmission line, when the transmitter is b
36、eing tested. 5.6 Test load for transmitters without accessible antenna terminals The test load shall be the antenna supplied by the manufacturer. 5.7 Limitation of the audio-frequency band Because some properties, for example noise and audio-frequency harmonic distortion, depend upon the audio-frequ
37、ency bandwidth of the test equipment, reproducible results can be obtained only when the band of audio frequencies occupied by the demodulated signal is restricted to specified limits. This restriction may be accomplished by means of a band-limiting filter preceding any audio-frequency measuring dev
38、ice. The filter may be incorporated within the measuring equipment. When measuring residual hum and noise, only the low-pass portion of the filter need be specified. NOTEThe input arrangement(4) may be a simulation network (seeSub-clause3.1), an impedance matching network, through connection, or any
39、 other specified network. Figure 1 Input-signal measuring arrangementBS6160-4:1981 BSI 04-2000 3 6 Characteristics of the measuring equipment Recommended characteristics of the measuring equipment are given in Appendix A. Section 2. Methods of measurement 7 Frequency error 7.1 Definition Frequency e
40、rror is the difference between the unmodulated carrier frequency and the assigned carrier frequency. The frequency error is expressed in parts per10 6or in hertz. 7.2 Method of measurement The frequency error is determined by measuring the carrier frequency in the absence of modulation. The accuracy
41、 of the measuring device must be at least ten times more precise than the frequency tolerance given in the equipment specification. If the carrier level is too low for direct measurement, the frequency of a sideband component may be measured when the transmitter is modulated with a precisely known f
42、requency, for example1000Hz. The frequency error may then be calculated taking this difference into account. NOTECare should be taken to ensure that the measurement is not affected by unwanted modulation products, such as hum. If required, the measurements may be repeated on each channel for which t
43、he transmitter is equipped to operate. 8 Terminal radio-frequency power This clause is applicable to transmitters equipped with suitable antenna terminals. 8.1 General The terminal radio-frequency power of a transmitter may contain: a carrier component (Sub-clause8.2 and8.3); modulation components d
44、etermining transmission quality, situated within the necessary bandwidth (Clauses12, 13, 14 and15); modulation components situated outside the necessary bandwidth (Sub-clause8.6); spurious narrow bandwidth components (Sub-clause8.4); spurious transmitter noise (Sub-clause8.5), and inter-transmitter
45、intermodulation products (Clause11). Measurements are normally made at the antenna terminals. Additional measurements may be made at the audio, control and power terminals using specified terminations. 8.2 Rated radio-frequency output power 8.2.1 Definition The peak envelope power (P p ) specified b
46、y the manufacturer which, under specified conditions of operation, should be available at the transmitter output terminals when the latter are connected to a specified load. 8.2.2 Method of measurement NOTEThis measurement is frequently made in conjunction with the measurement of the relative interm
47、odulation product level (Clause14) and ratio of carrier power to rated r.f. output power (Sub-clause8.3). 8.2.3 Method of measurement for emission ClassA3A or A3J a) Connect the equipment as illustrated in Figure 7, page 16. Apply audio-frequency signals of1000Hz and1600Hz from generators(2) and(6).
48、 b) Adjust the level of each audio-frequency signal according to the manufacturers instructions, to produce two necessary sidebands of equal level. c) Measure the average output power. Any convenient method which gives an accuracy of at least 10%, for example a radio-frequency wattmeter, may be used
49、. d) For emission type A3J, the rated radio-frequency output power is twice the value measured in stepc).BS6160-4:1981 4 BSI 04-2000 For emission type A3A, where carrier power is8.5dB below the level of either necessary sideband, the rated radio-frequency output power is2.64times the value measured in stepc). 8.2.4 Method of measurement for emission Class A3H a) Apply a signal of1000Hz from one of the generators of Figure 7. b) Adjust the level of the audio-frequency signal according to the manufacturers instructions, to produce a
