Coded excitation in space and time for the identification of geometric parameters using audio transducer arrays

Abstract

Impulse responses of a room can provide a lot of geometric information of acoustic systems. Loudspeaker and microphone array positions, locations of walls and scattering bodies are representative examples. To extract geometric information from the room impulse responses, the measurement time should be short enough such that the degradation of time delay estimation performance due to non-stationary environmental noises can be minimized. In this work, we attempt to enhance the SNR of the short-term measurement, by using a coded excitation technique in space and time. Both the spatially and temporally coded excitation signals are applied to a set of loudspeakers combined with microphones, and it is shown that the measurement time can be shortened with minimal loss of SNR and time delay estimation performance.