CHARACTERIZATION OF MICROWAVE 4-PARAMETER MATERIALS AND ITS APPLICATION IN WIDE-BAND RADAR ABSORBER DESIGN

A new free-space measurement technique for the characterisation of fou r-parameter microwave materials is presented. The method employed offe rs the advantage of evaluating the specimen under conditions close to those of the operational environment. In addition, it does not require reconfiguration of the system during the measurement process. The pro cedure is shown to be tolerant of measurement errors and provides good accuracy in the derived material parameters. The technique is validat ed by the design and evaluation of a practical absorber over a 6:1 fre quency range.