Robust farfield wideband beamformer design using worst-case performance optimization

In the previous work, we have proposed a robust design approach for nearfield wideband beamformers for microphone arrays using the worst-case performance optimization criterion. In this work, we fill the literature gap by extending the idea to farfield microphone arrays and establish the corresponding design principle. The key design parameters related to the farfield design approach in the presence of microphone mismatch errors are derived in this paper, followed by some numerical examples to illustrate the performance of the robust design.