IEC 61000-4-21-2003 pdf – Electromagnetic compatibility (EMC) – Part 4-21: Testing and measurement techniques – Reverberation chamber test methods.
1 Scope This part of IEC 61000 considers immunity and wanted and unwanted emissions tests for electric and/or electronic equipment and screening effectiveness tests. Only radiated phenomena are considered. It establishes the required test procedures for using reverberation chambers for performing radiated immunity, radiated emissions and screening effectiveness testing. The object of this part is to establish a common reference for using reverberation chambers to evaluate the performance of electric and electronic equipment when subjected to radio- frequency electromagnetic fields and for determining the levels of radio-frequency radiation emitted from electric and electronic equipment. NOTE Test methods are defined in this part for measuring the effect of electromagnetic radiation on equipment and the electromagnetic emissions from equipment concerned. The simulation and measurement of electro- magnetic radiation is not adequately exact for quantitative determination of effects. The test methods defined are structured for the primary objective of establishing adequate repeatability of results at various test facilities for qualitative analysis of effects. This part of IEC 61000 does not intend to specify the tests to be applied to particular apparatus or system(s). Its main aim is to give a general basic reference to all concerned product committees of the IEC. The product committees are to select emission limits and test methods in consultation with CISPR. The product committees remain responsible for the appropriate choice of the immunity tests and the immunity test limits to be applied to their equipment. This part of IEC 61000 describes other test methods than IEC 61000-4-3 and CISPR 16-2. The other methods may be used in consultation with CISPR and TC 77, if so specified by product committees. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies.
3 Definitions and acronyms 3.1 Definitions For the purposes of this part of IEC 61000-4, the following definitions, together with those in IEC 60050(161) apply. 3.1.1 antenna that part of a radio transmitting or receiving system which is designed to provide the required coupling between a transmitter or a receiver and the medium in which the radio wave propagates [IEV 712-01-01] NOTE For the purpose of this procedure antennas are assumed to have an efficiency of 75 % or greater. 3.1.2 electromagnetic (EM) wave variations of the conditions of a material medium or vacuum, characterized by a time-varying electromagnetic field, and moving with a velocity defined at each point and in each direction by the properties of the medium NOTE An electromagnetic wave is produced by variations of electric charges or of electric currents. [IEV 121-11-63] 3.1.3 far field region 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 proportion to the distance from the antenna. NOTE 2 For a broadside antenna having a maximum overall dimension, D, which is large compared to the wave- length, λ , the far field region is commonly taken to exist at distances greater than λ 2 2D from the antenna in the direction of maximum radiation. [IEV 712-02-02] 3.1.4 field strength measurement, made in the far field, of either the electric or the magnetic component of the field and expressed as V/m or A/m; any one of these measurements may be converted into the others NOTE 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.