Beamformer improvement with increasing number of sensors
Matthew J. Berry, Michael E. Lockwood, Douglas L. Jones, Robert C. Bilger, Charissa R. Lansing, William D. O’Brien, Bruce C. Wheeler, Albert S. Feng · The Journal of the Acoustical Society of America · 2001
The two-sensor frequency-banded minimum-variance beamformer (FBMVB) [Lockwood et al., J. Acoust. Soc. Am. 106, 2278 (1999)], shown to extract a target speech signal from multiple interfering speech sources, is extended to three and four sensors. The extended FBMVB retains the real-time computational advantages of the two-sensor FBMVB. Results from a battery of simulated and real acoustic environment tests suggest that the extended FBMVB offers better extraction of the target speech than the two-sensor FBMVB. Measuring the quality of extraction as signal-to-noise ratio gain and intelligibility-weighted signal-to-noise ratio gain, the extended FBMVB demonstrates performance improvements of 2–3 dB over the already high performance of the two-sensor FBMVB for most tests. In general, results suggest that the extended FBMVB is more robust with respect to crowded interferer settings and room reverberation.