Blind Interference Suppression using Polyphase Channelizers and Rank-Reduced Array Processing

This paper proposes a novel blind beamforming approach to address complex narrowband interference environments where the precise array configuration is unknown. The received signal is decomposed into orthogonal narrowband partitions using a polyphase filter bank channelizer, and a rank-reduced version of the received matrix on each sub-channel is computed through reconstruction by retaining a subset of its singular value (SV)s. The wideband spectrum of each is synthesized through a near-perfect polyphase reconstruction filter, and a composite wideband spectrum is obtained from the maximum eigenvector of the resulting covariance matrix. The resulting process is shown to suppress numerous interference sources (in special cases even with more than the degrees of freedom of the array), all with little knowledge of the primary signal of interest and array configuration. Results are validated in simulation.