Bistatic radar denial by spatial waveform diversity

The purpose of this paper is to introduce and evaluate a number of techniques to prevent a radar being used by an adversary as a bistatic illuminator of opportunity. These are all based on the idea of radiating a so-called "masking signal" which is arranged to be orthogonal, both in a spatial sense and in a coding sense, to the radar signal, and of a level sufficient to mask the radar signal to an adversary, and hence to deny a reference for bistatic operation. The overall performance of the scheme is quantified in terms of two parameters: (i) the degree of masking of the radar signal by the masking signal, and (ii) the degree of suppression of echoes (from targets or from clutter) of the masking signal in the channels of the radar receiver. The choice of waveforms is considered, followed by a description of two approaches to the choice of radiation patterns, and then the results of some simulations of the overall performance are presented.