A novel affine projection algorithm for superdirective microphone array beamforming

This paper describes a new adaptive algorithm and assesses its effectiveness within speech enhancement applications. The proposed variable step size block exact APA (VSS-BEAPA) filtering is based on the affine projection algorithm (APA) and introduces a block processing with a variable step size that allows to consider under-modeling scenarios. The algorithm shows improved convergence performance and computational efficiency and its robustness is proved in a typical context of a hands-free teleconferencing application in a noisy environment. The experiments show that a microphone array system joined with VSS-BEAPA filtering is capable of both decreasing the noise level and enhancing the speech signal quality.