A nonlinear suppression technique for range ambiguity resolution in pulse Doppler radars

This paper reintroduces a novel range ambiguity resolution technique, invented by Palermo (1962), called nonlinear suppression. A set of M unique modulations is selected which have desirable (mutually dispersive) cross-correlation properties. The transmitted pulse train is constructed by successively modulating each pulse with one of the M modulations. The received data are processed in M independent receiver channels with each channel corresponding to a single modulation. Ideally, the channels are designed such that the output response is only dependent upon one of the modulations (versus all M). This is accomplished to a useful extent with Palermo's technique by progressively removing unwanted contributions on a range cell by range cell basis. By passing the received data through an appropriate memoryless nonlinearity, the process preferentially removes energy from data responsive to each of the other M-1 codes.