Frequency tuning characteristics of capacitively loaded Salisbury screen radar absorber

The frequency characteristics of a Salisbury screen radar absorber that incorporates a layer exhibiting both resistive and capacitive properties are considered. If the capacitance is fixed, the absorber thickness and hence weight may be reduced but at the expense of bandwidth. If the capacitance is variable then the absorber may be tuned via an external control signal. The practical limitations of both applications are discussed in relation to recent advances in conducting polymer materials