TY - GEN
T1 - Worst-case performance optimization for spherical microphone array modal beamformers
AU - Sun, Haohai
AU - Yan, Shefeng
AU - Svensson, U. Peter
PY - 2011
Y1 - 2011
N2 - The performance of conventional spherical microphone array modal beamformers is known to degrade in the presence of array errors. White noise gain control has been widely used to control the robustness of modal beamformers, but it is not clear how to properly choose the white noise gain parameters based on the level of array errors. In this paper, a worst-case performance optimization approach is formulated for the spherical array minimum-sidelobe modal beamformer to improve its robustness against random errors occurring in practice, thus the optimal performance can be obtained based on the known maximum level of array errors. The robust optimal modal beamforming problem is reformulated as a tractable convex optimization within the spherical harmonics framework. Compared with conventional element-space approaches, the proposed modal beamforming method enjoys lower optimization complexity and higher flexibility in beam steering.
AB - The performance of conventional spherical microphone array modal beamformers is known to degrade in the presence of array errors. White noise gain control has been widely used to control the robustness of modal beamformers, but it is not clear how to properly choose the white noise gain parameters based on the level of array errors. In this paper, a worst-case performance optimization approach is formulated for the spherical array minimum-sidelobe modal beamformer to improve its robustness against random errors occurring in practice, thus the optimal performance can be obtained based on the known maximum level of array errors. The robust optimal modal beamforming problem is reformulated as a tractable convex optimization within the spherical harmonics framework. Compared with conventional element-space approaches, the proposed modal beamforming method enjoys lower optimization complexity and higher flexibility in beam steering.
KW - Spherical microphone array
KW - beamforming
KW - spherical harmonics
KW - worst-case performance optimization
UR - http://www.scopus.com/inward/record.url?scp=79961163891&partnerID=8YFLogxK
U2 - 10.1109/HSCMA.2011.5942405
DO - 10.1109/HSCMA.2011.5942405
M3 - Conference contribution
AN - SCOPUS:79961163891
SN - 9781457709999
T3 - 2011 Joint Workshop on Hands-free Speech Communication and Microphone Arrays, HSCMA'11
SP - 31
EP - 35
BT - 2011 Joint Workshop on Hands-free Speech Communication and Microphone Arrays, HSCMA'11
T2 - 2011 Joint Workshop on Hands-free Speech Communication and Microphone Arrays, HSCMA'11
Y2 - 30 May 2011 through 1 June 2011
ER -