Article

Test method for electromagnetic radiation safety margin combined injection with radiation

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Abstract

As to the technology requirements of electromagnetic compatibility and protection performance test for system, considering the problems existed in traditional electromagnetic susceptibility test method, we put forward an electromagnetic radiation safety margin test method combined injection with radiation. Considering the equal response voltage on the equipment input port as equivalent principle rather than the distributive current on the cable, the equivalence between injection and radiation was theoretically analyzed. By adopting antisymmetric directional coupler cascade design scheme, the S parameter of coupling module with six ports was calculated. Moreover, the effect test method of using injection as an equivalent substitute for radiation based on coupling module was put forward. The typical antenna receiving system was selected as equipment under test. By carrying out injection and radiation effect test, under the condition of equal output response, the curvilinear relation between radiated field intensity and injection voltage was determined. The validity of electromagnetic radiation safety margin test method combined injection with radiation was verified.

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... The research on margin has mainly focused on test method and equipment level or critical circuits [3][4][5] , or statistical method evaluation [6] , safety margin design [7] , etc. However, for large-scale complex systems such as ships and airplanes, which are integrated with a variety of equipment, the electromagnetic energy coupling relationship is complex, and the verification methods of various types of EME vary widely [8] . ...
... For the high-intensity electromagnetic field, in addition to the radiation method, the injection method [5] and other equivalent method [25] can also be used. Choosing appropriate injection test method can ensure the consistency of injection and radiation test results, as shown in Fig.8. ...
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