Screening measurements in the time domain and their conversion into the frequency domain

In the measurement of screening of cables and connectors it is found that a dedicated instrument working in the time domain has many advantages over a swept frequency set-up. Comparison is made using calibration circuits to simulate the screening properties of connectors as well as on genuine cable assemblies. Using the simplest possible relationship between time and frequency domains, quite good agreement can be reached whether the measurement is made on a calibrator or a real connector. The conversion can be used on the homogeneous screen of a semi-rigid cable if care is taken in its application.