Signal processing applications for sound field measurements using instantaneous array input

Most existing acoustic signal processing techniques have been developed in the frequency domain. These techniques are suitable for single-frequency signals, but most actual sound fields are wideband. To apply frequency-domain techniques to wideband signals, it is necessary to wait the time required for processing before performing the discrete Fourier transform, and then apply processing to each frequency bin. This study describes acoustic signal processing techniques using the instantaneous input of a microphone array are described. These techniques are suitable for real-time implementation because they avoid the above disadvantages. The limitations and disadvantages of methods using only instantaneous information are also discussed.