Using coprime microphone arrays for direction-of-arrival estimation

Abstract

Direction-of-arrival estimation using microphone arrays requires many sensors to reduce beam width in order to achieve precise location estimation in a noisy environment. Coprime linear microphone arrays allow for narrow beams with fewer sensors. Coprime sensing is a type of sparse sensing, meaning that the microphone elements are fewer and more spaced out than in a traditional array without sacrificing resolution, but requiring more post-processing. A coprime microphone array is made up of two overlapping uniform linear arrays with M and N sensors, where M and N are coprime. By applying spatial filtering with both arrays and combining their outputs, M+N sensors can yield MN directional bands. In this work, the coprime array theory is implemented experimentally for the first time with a microphone array to estimate the location of multiple uncorrelated sources in a noisy environment. Both simulated and measured results will be discussed.