A proposal to use polarization information to enhance a simple ESM receiver system based around a circular antenna array

Recent interest in improved methods to passively detect and characterize sources of electromagnetic radiation and radar targets has concentrated research into the ability of new and existing systems to perform an Electronic Support Measures (ESM) role. Many existing radar and communication systems inherently derive information which could be exploited by an ESM analyser, but, in general, ignore that information associated with the polarization state of signals. This paper contains a proposal to show how a circular antenna array system intended for use with communication signals can be extended, relatively simply, to perform an ESM function. In addition the ESM system proposed uses all the information inherently available in the electromagnetic wave, in particular, exploiting the information contained in the polarization state of received signals.