Applying Virtual Microphones to Triangular Microphone Array in in-Car Communication

We have evaluated the application of the wavelength-proportional arrangement of virtual microphones (WPVM) to a triangular microphone array in a real car environment. Beamforming is effective for speech enhancement in in-car communication. However, it is difficult to install a sufficient number of microphones for beamforming in a car. In this paper, we propose a virtual microphone technique that increases the number of microphones virtually to achieve high speech enhancement performance with a small number of microphones in a car. We applied the virtual microphone technique to a triangular microphone array in a car and evaluated the adaptive beamforming performance. As a result, the WPVM was shown to be effective for improving the performance of speech enhancement in a car.