Reduced complexity MVDR broadband beamspace beamforming under frequency invariant constraint

A minimum variance distortionless response algorithm under a frequency invariant constraint (MVDR-FI) for broadband signal environments is presented. The algorithm utilizes a novel underlying beamspace beamforming structure with an inherent constraint that synthesizes a far-field response with minimal variation with frequency, leading to complexity reduction and subsequent improvement in convergence speed. Simulation results are presented to illustrate the performance of the beam space MVDR-FI with respect to the Frost (1972) beamformer and a previously proposed FIB-based MVDR algorithm.