1、 I n t e r n a t i o n a l T e l e c o m m u n i c a t i o n U n i o n ITU-T K.127 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (07/2017) SERIES K: PROTECTION AGAINST INTERFERENCE Immunity requirements for telecommunication equipment in close proximity use of wireless devices Recommendation ITU-T
2、 K.127 Rec. ITU-T K.127 (07/2017) i Recommendation ITU-T K.127 Immunity requirements for telecommunication equipment in close proximity use of wireless devices Summary Recommendation ITU-T K.127 specifies the immunity requirements for equipment used in the telecom facilities where wireless local are
3、a network (WLAN) devices are used in close proximity. This Recommendation is established in order to avoid malfunctions of the equipment due to radio frequency (RF) signals of devices. It contains requirements including test levels, test signal, test procedures and test facilities. History Edition R
4、ecommendation Approval Study Group Unique ID* 1.0 ITU-T K.127 2017-07-29 5 11.1002/1000/13281 Keywords Close proximity, radiated immunity, vicinity, wireless devices. * To access the Recommendation, type the URL http:/handle.itu.int/ in the address field of your web browser, followed by the Recommen
5、dations unique ID. For example, http:/handle.itu.int/11.1002/1000/11830-en. ii Rec. ITU-T K.127 (07/2017) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU T
6、elecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardizati
7、on Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technol
8、ogy which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance
9、 with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with the Recommendation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligat
10、ory language such as “must“ and the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required of any party. INTELLECTUAL PROPERTY RIGHTSITU draws attention to the possibility that the practice or implementation o
11、f this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the
12、 date of approval of this Recommendation, ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementers are cautioned that this may not represent the latest information and are therefore strongly urged to con
13、sult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2017 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T K.127 (07/2017) iii Table of Contents Page 1 Scope . 1 2 References . 1 3 Defini
14、tions 1 3.1 Terms defined elsewhere 1 3.2 Terms defined in this Recommendation . 2 4 Abbreviations and acronyms 2 5 Conventions 2 6 Test condition and test method . 2 6.1 Test level and waveforms . 3 6.2 Equipment configuration and general operation during test 3 6.3 Test equipment . 4 6.4 Verificat
15、ion of the uniformity of the electric field . 4 6.5 Test facility . 4 6.6 Arrangement of equipment under test (EUT) . 4 6.7 Test procedures . 4 6.8 Evaluation of test results 5 6.9 Test report . 5 Appendix I The rationale of decision for the test level . 6 I.1 Introduction 6 I.2 Measurement of elect
16、ric field strength in the vicinity of dipole antenna . 6 Appendix II The protection distance considering the radio law of each country . 9 II.1 Introduction 9 II.2 Protection distance 9 Bibliography. 10 iv Rec. ITU-T K.127 (07/2017) Introduction In recent years, the usage of tablet terminals connect
17、ed to the wireless local area network has been widely spread because it helps to improve efficiency of maintenance work in the telecommunication equipment rooms. The work procedures or the indication from remote operators are displayed on the tablets. It is possible for workers to improve their effi
18、ciency by watching the displays while they work. In addition, with the Internet of things (IoT), it is assumed that the various sensors installed in the telecommunication equipment room are connected wirelessly. Therefore, when the various wireless devices are used in close proximity to telecom equi
19、pment, the radio waves emitted from these devices can cause malfunction of telecom equipment. This Recommendation defines radiated immunity requirements and test procedures assuming the usage of wireless devices in the vicinity of telecom equipment. Rec. ITU-T K.127 (07/2017) 1 Recommendation ITU-T
20、K.127 Immunity requirements for telecommunication equipment in close proximity use of wireless devices 1 Scope This Recommendation specifies the immunity requirements for telecommunication equipment when radio-frequency transmitters are used in close proximity. It covers immunity requirements in the
21、 frequency range of 2.4 GHz, 5.2 GHz and 5.6 GHz band considering the usage of wireless LAN devices. This Recommendation is part of product family Recommendations applicable to equipment intended to be installed in telecommunication facilities, including switching equipment, transmission equipment,
22、radio equipment, power supply equipment, supervisory equipment and control equipment. The Recommendation gives the minimum test levels to avoid malfunctions in a given environment. The requirements given in specific product Recommendations supersede those given in this Recommendation. 2 References T
23、he following ITU-T Recommendations and other references contain provisions which, through reference in this text, constitute provisions of this Recommendation. At the time of publication, the editions indicated were valid. All Recommendations and other references are subject to revision; users of th
24、is Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendations and other references listed below. A list of the currently valid ITU-T Recommendations is regularly published. The reference to a document within this Recommendation d
25、oes not give it, as a stand-alone document, the status of a Recommendation. ITU-T K.43 Recommendation ITU-T K.43 (2009), Immunity requirements for telecommunication network equipment. IEC 61000-4-3 IEC 61000-4-3:2006, Electromagnetic compatibility (EMC) Part 4-3: Testing and measurement techniques R
26、adiated, radio-frequency, electromagnetic field immunity test. IEC 61000-4-39 IEC 61000-4-39:2017, Electromagnetic compatibility (EMC) Part 4-39: Testing and measurement techniques Radiated fields in close proximity Immunity test. 3 Definitions 3.1 Terms defined elsewhere This Recommendation uses th
27、e following terms defined elsewhere: 3.1.1 auxiliary equipment (AE) b-IEC 61000-4-4: Equipment necessary to provide the equipment under test (EUT) with the signals required for normal operation and equipment to verify the performance of the EUT. 3.1.2 electric field strength b-ITU-T K.83: Magnitude
28、of a field vector at a point that represents the force (F) on a small test charge (q) divided by the charge: qFEThe electric field strength is expressed in units of volt per metre (V/m). 2 Rec. ITU-T K.127 (07/2017) 3.1.3 electromagnetic compatibility (EMC) b-IEC 60050-161: Ability of equipment to f
29、unction satisfactorily in its electromagnetic environment without introducing intolerable electromagnetic disturbances to anything in that environment. 3.1.4 far field region b-ITU-T K.52: That region of the field of an antenna where the angular field distribution is essentially independent of the d
30、istance from the antenna. In the far-field region, the field has a predominantly plane-wave character, i.e., locally uniform distribution of electric field strength and magnetic field strength in planes transverse to the direction of propagation. 3.1.5 immunity (to a disturbance) b-IEC 60050-161-01-
31、20: The ability of a device, equipment or system to perform without degradation in the presence of an electromagnetic disturbance. 3.1.6 immunity test level b-IEC 60050-161-04-41: The level of a test signal used to simulate an electromagnetic disturbance when performing an immunity test. 3.1.7 radio
32、 frequency (RF) IEC 61000-4-39: Frequency in the portion of the electromagnetic spectrum that is between the audio-frequency portion and the infrared portion and that is useful for radio transmission. 3.2 Terms defined in this Recommendation None. 4 Abbreviations and acronyms This Recommendation use
33、s the following abbreviations and acronyms: AE Auxiliary Equipment AM Amplitude Modulation EMC Electromagnetic Compatibility EUT Equipment Under Test IoT Internet of Things OFDM Orthogonal Frequency Division Multiplexing PM Pulse Modulation RF Radio Frequency TEM Transverse Electromagnetic WLAN Wire
34、less Local Area Network 5 Conventions None. 6 Test condition and test method When the WLAN devices are used in the vicinity of telecom equipment, intense electric field will be locally illuminated to the equipment. The electric field strength of WLAN devices at the distance of 1 cm is about 30 V/m (
35、see Appendix I). A test method simulating the usage of WLAN devices in the vicinity of telecom equipment is demonstrated in IEC 61000-4-39. For the purpose of this Recommendation IEC 61000-4-39 is used as a base text and specifies the immunity test method for telecom equipment and a minimum of test
36、level. Rec. ITU-T K.127 (07/2017) 3 6.1 Test level and waveforms The immunity test level is given in Table 1. This test level is the amplitudes of the unmodulated carrier signal (see Figure 1 a) for level calibration. Performance criteria are in accordance with clause 6.1 of ITU-T K.43. The test wav
37、eform defined in Table 2 shall be applied to equipment under test (EUT) individually. Table 1 Test level Test level Unit Performance criterion Basic standard Frequency range (MHz) Frequency step (MHz) 30 V/m A IEC 61000-4-39 2 400-2 485 5 170-5 330 5 490-5 710 1 MHz NOTE 1 The test level may be chan
38、ged only if there are specific reasons requiring a different test level and there are agreement on this between telecom operators and manufacturers. NOTE 2 Performance criteria are in accordance with clause 6.1 of ITU-T K.43. Table 2 Test waveforms Test waveform Specification Figure of test waveform
39、 AM (Amplitude Modulation) Depth: 80% Rate: 1 kHz sine wave see Figure 1 b) PM (Pulse Modulation) Duty cycle: 50% Modulation frequency: 217 Hz see Figure 1 c) Figure 1 Waveforms for test level calibration and for the test (from IEC 61000-4-39)1 6.2 Equipment configuration and general operation durin
40、g test This configuration and operation is in accordance with clause 5 of ITU-T K.43. 1 IEC 61000-4-39 ed.1.0 Copyright 2017 IEC Geneva, Switzerland. www.iec.ch. 4 Rec. ITU-T K.127 (07/2017) 6.3 Test equipment The test equipment is in accordance with clause 6.2.2 of IEC 61000-4-39. However, the use
41、of transverse electromagnetic (TEM) horn antenna specified as a radiating antenna is not mandatory. 6.4 Verification of the uniformity of the electric field The electric field uniformity of radiating antenna shall be verified in accordance with Annex A.4 of IEC 61000-4-39. 6.5 Test facility The test
42、 facility is in accordance with clause 7.2.1 of IEC 61000-4-39. 6.6 Arrangement of equipment under test (EUT) The arrangement of EUT is in accordance with clause 7.2.2 of IEC 61000-4-39. 6.7 Test procedures First of all, the setting of the test level is performed in accordance with section 8.6.1 of
43、IEC 61000-4-39. The test shall then be performed in accordance with the following procedures: (1) Divide the surface of the EUT into a grid based on the size of the uniform electric field plane according to clause 6.4. (2) Install the radiating antenna 100 5 mm away from the EUT to apply a verticall
44、y polarized wave to the EUT. The axis of the radiation direction of the antenna shall be aligned with the centre of the grid. (3) The test frequency output power of the signal generator for the radiating antenna shall be set to the value obtained through the calibration described above. (4) Apply AM
45、 signal as a test waveform to the EUT, and confirm the correct operation of the EUT using a monitoring device or other checking tools (bit error measurement apparatus, packet error measurement apparatus, etc.). (5) Change the test frequency and execute (4) above. (6) Apply PM signal as a test wavefo
46、rm to the EUT, and confirm the correct operation of the EUT using a monitoring device or other checking tools (bit error measurement apparatus, packet error measurement apparatus, etc.). (7) Change the test frequency and execute (6) above. (8) Apply a horizontally polarized wave to the EUT, and exec
47、ute (4) to (7) above. (9) Move the radiating antenna to the next grid, and execute (4) to (8) above. In undertaking the above test procedures, attention should be given to the following: a) Tests shall be performed with all covers and panels opened or removed. b) The pulse modulation carrier of each
48、 test frequency shall be present for a longer time than is needed for the EUT to operate and respond (e.g., the processing time of the EUT). In any case, it shall be no shorter than 1 second. c) Tests shall be conducted for all sides. However, no test is needed on any side if one part (panel, etc.)
49、is no smaller than 1.5 times the uniform electric field plane of the electromagnetic field generating antenna, which is made of a uniform metal that is 0.25 mm or thicker, and is not to be removed at the time of maintenance work, etc. (e.g., the bottom or ceiling side of the EUT). d) The radiating antenna shall not be moved while it is applying test signals. Rec. ITU-T K.127 (07/2017) 5 6.8 Evaluation of test results The test results shall be classified in terms of the loss of function or degradation of
