Preprint: "Theory and design of multirate microphone arrays" by O. Jahromi and P. Aarabi

[Omid Jahromi (omidj@control.toronto.edu)]

Title: Theory and design of multirate microphone arrays

Authors: Omid Jahromi and Parham Aarabi

Journal: IEEE Transactions on Signal Processing (submitted)

Preprint available from http://www.multirate.org

Abstract:
This paper considers the problem of fusing the discrete-time signals generated by a low-resolution microphone array to emulate a single high-resolution recording. We formulate this problem as a multirate analysis/synthesis problem and demonstrate how the presence of time delay of arrival (TDOA) makes it more involved than standard problems encountered in multirate signal processing. We show that reliable TDOA estimation is possible provided that the analysis filters used in the measurement process satisfy specific phase and amplitude response requirements. We then introduce sample FIR and IIR designs that satisfy these requirements. At the end, we devise a fusion procedure for the low-rate measured data once the TDOA is estimated. We use H_infinity optimality criterion and design fusion filters which can reconstruct a high-resolution measurement for all TDOA values and with guaranteed precision.