An em method for multichannel toa and doa estimation of acoustic echoes

The time-of-arrivals (TOAs) of acoustic echoes is a prerequisite in, e.g., room geometry estimation and localization of acoustic reflectors, which can be an enabling technology for autonomous robots and drones. However, solving these problems alone using TOAs introduces the difficult problem of echolabeling. Moreover, it is typically suggested to estimate the TOAs by estimating the room impulse response, and finding the peaks of it, but this approach is vulnerable against noise (e.g., ego noise). We therefore propose an expectation-maximization (EM) method for estimating both the TOAs and direction-of-arrivals (DOAs) of acoustic echoes using a loudspeaker and a uniform circular array (UCA). Our results show that this approach is more robust against noise compared to the traditional peak finding approach. Moreover, they show that the TOA and DOA information can be combined to estimate wall positions directly without considering echolabeling.