Overdetermined blind source separation of real acoustic sounds based on multistage ICA using subarray processing

We propose a new algorithm for overdetermined blind source separation (BSS) based on multistage independent component analysis (MSICA). To improve the separation performance, we have proposed MSICA in which frequency-domain ICA and time-domain ICA are cascaded. In the original MSICA. the specific mixing model, where the number of microphones is equal to that of sources, was assumed. However, the additional microphones should be required to achieve a better separation performance under reverberant environments. This yields alternative problems, e.g., a complication of the permutation problem. In order to solve them, we propose a new extended MSICA using subarray processing, where the number of microphones and that of sources are set to be the same in every subarray. The experimental results obtained under the real environment reveal that the separation performance of the proposed MSICA is improved as the number of microphones is increased.