Reduced-Complexity Binaural Source Localization for Headphones and Hearing Aids using Low-Rank DRTF Approximations

Abstract:
Direction of arrival estimation in headphones and hearing aids remains challenging, as the conflict between battery run time and accuracy has to be balanced. We propose an algorithm that reduces the computational complexity of a steered response power algorithm that uses a superdirective filter-and-sum beamformer. Within this algorithm, device-related transfer functions (DRTFs) are used that are the main source of complexity especially for multi-microphone devices. Our proposed algorithm uses a low-rank approximation on these DRTFs as an offline step before run time. We evaluate the algorithm by simulations based on measurements of modified multi-microphone circumaural headphones. It can be shown that we can reduce the computational complexity of the algorithm by 77% at a comparable performance compared to the reference algorithm.