Space-time adaptive processing for clutter suppression in coprime array and coprime pulse repetition interval airborne radar

Abstract

This paper develops two novel space-time adaptive processing (STAP) filters for clutter suppression in airborne radar with the coprime space-time sampling, which is realized by the coprime array and coprime pulse repetition interval (PRI). Different from the conventional STAP filters, the proposed STAP filters are derived by three steps. Firstly, a virtual space-time snapshot is constructed using the property of the coprime sampling. Secondly, an equivalent covariance matrix with enhanced degrees of freedom is computed by using spatial-temporal smoothing approach. Thirdly, two optimal STAP filters are derived based on the estimated covariance matrix. Simulations are conducted to validate the effectiveness of the proposed filters.