Tetrahedral microphone system for a virtual cardioid microphone

摘要

Since every waveform can be subdivided into one or more sinusoids, spatial audio information at a given observation point can be approximated by giving the amplitude, phase and wave normal direction of each sine wave. The wave normal direction of each sine wave can be obtained by using a 4-channel tetrahedral microphone system. By using the obtained spatial audio information, sound from particular direction can be enhanced or suppressed programmatically. By converting 3-D vectors to 8-bit digits, spatial audio information can be transmitted at a low bit rate. It allows the user to pick up or reject sound from any requested direction during the reproduction.