GB/T 17626.39-2023 Electromagnetic compatibility - Testing and measurement techniques-Part 39 : Radiated fields in close proximity immunity test
1 Scope
This document specifies immunity requirements for electrical and electronic equipment when it is exposed to radiated electromagnetic energy from RF transmitters used in close proximity. It establishes test levels and the required test procedures. The applicable frequency range is 9 kHz to 6 GHz. Fixed-installation equipment being exposed to portable transmitting devices, mobile equipment exposed to fixed transmitting devices and mobile equipment exposed to other mobile transmitting devices are considered.
The object of this document is to establish a common reference for evaluating the immunity requirements of electrical and electronic equipment that is exposed to radiated, RF electromagnetic fields from sources at close distances. It is understood that this document does not replace general immunity requirements of electrical and electronic equipment to radiated electromagnetic energy as given in IEC 61000-4-3 and other parts of IEC 61000 and that it is only applicable if an equipment or system is exposed to disturbance sources in close proximity.
In the context of this document, "close proximity" generally refers to a separation distance between the source and victim equipment of less than or equal to 200 mm for frequencies greater than 26 MHz and 500 mm for frequencies lower than 26 MHz.
The test methods documented in this document describe consistent methods to assess the immunity of an equipment or system against a defined phenomenon in the respective frequency range. Product committees would consider the applicability of the test and then if necessary select the applicable test method depending on the EUT, frequency range, disturbance source, etc.
Note: As described in IEC Guide 107, this is a basic EMC publication for use byproduct committees of the IEC. As also stated in Guide 107, the IEC product committees are responsible for determining whether this immunity test standard shall be applied or not, and if applied, they are responsible for determining the appropriate test levels and performance criteria.
This document deals with immunity tests related to RF magnetic and electromagnetic fields from any source used in close proximity to other electrical or electronic equipment or systems.
This document is an independent test method. Other test methods should not be used as substitutes for claiming compliance with this document.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
IEC 60050-161 International Electrotechnical Vocabulary (IEV) - Part 161: Electromagnetic compatibility (available at www.electropedia.org)
Note: GB/T 4365-2003 Electrotechnical terminology - Electromagnetic compatibility (IEC 60050-161 :1990, IDT)
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-161 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
IEC Electropedia: available at http: //www.electropedia.org/
ISO Online browsing platform: available at http: //www.iso.org/obp
Note: Where the terms “voltage” and “current” are used in this document, they mean the r.m.s. values of an alternating or direct voltage or current unless stated otherwise.
3.1.1
electromagnetic compatibility; EMC
ability of equipment to function satisfactorily in its electromagnetic environment without introducing intolerable electromagnetic disturbances to anything in that environment
[Source: GB/T 4365-2003, 161-01-07]
3.1.2
electromagnetic disturbance
any electromagnetic phenomenon which can degrade the performance of a device, equipment or system or adversely affect living or inert matter.
Note: An electromagnetic disturbance can be electromagnetic noise, an unwanted signal or a change in the propagation medium itself.
[Source: GB/T 4365-2003, 161-01-05]
3.1.3
(electromagnetic) emission
phenomenon by which electromagnetic energy emanates from a source
[Source: GB/T 4365-2003, 161-01-08]
3.1.4
electromagnetic environment
totality of electromagnetic phenomena existing at a given location
Note: In general, the electromagnetic environment is time dependent and its description may need a statistical approach.
[Source: GB/T 4365-2003, 161-01-01]
3.1.5
far field
that region of the electromagnetic field of an antenna wherein the predominant components of the field are those which represent a propagation of energy and wherein the angular field distribution is essentially independent of the distance from the antenna
Note 1: In the far field region, all the components of the electromagnetic field decrease in inverse
Note 2: For a broadside antenna having a maximum overall dimension D which is large compared to the wavelength λ, the far field region is commonly taken to exist at distances greater than 2D2/λ, from the antenna in the direction of maximum radiation.
[Source: GB/T 14733.10-2008, 712-02-02, modified -the word "region" has been removed from the term]
3.1.6
field strength
electric or magnetic component of the field
Note 1: Field strength maybe expressed as V/m or A/m.
Note 2: For measurements made in the near field, the term "electric field strength" or "magnetic field strength" is used according to whether the resultant electric or magnetic field, respectively, is measured. In this field region, the relationship between the electric and magnetic field strength and distance is complex and difficult to predict, being dependent on the specific configuration involved. Inasmuch as it is not generally feasible to determine the time and space phase relationship of the various components of the complex field, the power flux density of the field is similarly indeterminate.
3.1.7
immunity (to a disturbance)
ability of a device, equipment or system to perform without degradation in the presence of an electromagnetic disturbance
[Source: GB/T 4365-2003, 161-01-20]
3.1.8
immunity test level
the level of a test signal used to simulate an electromagnetic disturbance when performing an immunity test
[Source: GB/T 4365-2003, 161-04-41]
3.1.9
near field
reactive near field (region)
that region of space immediately surrounding an antenna, where the predominant components of the electromagnetic field are those which represent an exchange of reactive energy between the antenna and the surrounding medium
[Source: GB/T 14733.10-2008, 712-02-01, modified -in the term, "induction field (region)" has been replaced by "near field".]
3.1.10
polarisation
orientation of the electric field vector of a radiated field
3.1.11
radio frequency; RF
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 Abbreviated terms
For the purposes of this document, the following abbreviated terms apply.
AM: Amplitude Modulation
CDMA: Code Division Multiple Access
DECT: Digital Enhanced Cordless Telecommunication
EUT: Equipment Under Test
FM: Frequency Modulation
GSM: Global System for Mobile Communication
LTE: Long Term Evolution
RFID: Radio- frequency Identification
TEM: Transverse Electromagnetic
TETRA: Trans- European Trunked Radio
VSWR: Voltage Standing Wave Ratio
WLAN: Wireless Local Area Network
4 General
Immunity of EUTs to disturbances from RF transmitters can be tested using several different methods, including those described in IEC 61000-4-3, IEC 61000-4-20, IEC 61000-4-21, IEC 61000-4-22 and this document, as shown in Figure 1. This document describes test methods unique to the situation in which the transmitter is used in close proximity to the EUT and the case of inhomogeneous magnetic fields (see Figure 2). In this context, "close proximity" generally refers to separation distances between the transmitter and the equipment of 200 mm or less for RF fields (frequencies greater than 26 MHz) and 500 mm for magnetic fields (frequencies lower than 26 MHz). Fixed-installation equipment being exposed to portable transmitting devices, mobile equipment exposed to fixed transmitting devices and mobile equipment exposed to other mobile transmitting devices are considered.
