Energy-based multi-speaker voice activity detection with an ad hoc microphone array

In this paper, we propose an energy-based technique to track the power of multiple simultaneous speakers using an ad hoc microphone array with unknown microphone positions. By considering the short-term power of the microphone signals, the problem can be converted into a non-negative blind source separation (NBSS) problem. By exploiting the prior knowledge that the source signals are non-negative and well-grounded, very efficient algorithms can be used to solve this NBSS problem, based only on second order statistics. We provide simulation results that demonstrate the effectiveness of the presented algorithm.