Title: Designs and implementations of broadband beamformers
Author: YAN Shefeng
Affiliation: 1. Institute of Acoustics, Chinese Academy of Sciences; 2. University of Chinese Academy of Sciences
Abstract: The designs and implementations of broadband beamformers are reviewed and discussed. Broadband beamformer includes discrete Fourier transform (DFT) implementation of a frequency-domain beamformer and finite impulse response (FIR) implementation of a time-domain beamformer. The designs of weights at each frequency bin for the DFT beamformer and that of FIR filters associated with each sensor for the FIR beamformer are both introduced. Performance analysis and comparisons for several typical approaches to them are presented. A unified approach, i.e., multiple-constrained approach, to narrowband beamformer is provided and is extended to the FIR implementation of broadband case. The unified approaches include the existing individual approaches as their special cases, which leads to much more flexible designs. Design examples of broadband robust adaptive beamformer with constant mainlobe response and controlled sidelobes are given to illustrate the behavior.