Abstract：The coupling-decoupling network (CDN) is widely applied in electromagnetic compatibility (EMC) for conducted radio frequency susceptibility tests. The impedance of equipment under test (EUT) port is the most important parameters in CDN calibration. To measure the impedance, adapters are required to connect the vector network analyzer (VNA) to the EUT port of the CDN. Until now, the impact of the adapters used has not been clearly demonstrated by the domestic calibration laboratories, while the impedance errors at high frequencies are caused by the adapters. Therefore, basing on experimental and theoretically calculating principles, two methods, which are defined as self calibration of VNA after coaxially converting and calculation by electrical length compensation, have been presented. The data indicate that the two methods are valid for removing the adpaters' impact, and the impedance measurement results have be improved.
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2019, Vol. 40 
