Self-localization and channel synchronization of smartphone arrays using sound emissions

摘要

In this paper, we propose a simple calibration method for an ad hoc microphone array that utilizes sound emissions. Assuming that each device has a function to record sound while emitting another sound, the location, the recording time offset, and the sampling frequency mismatch of each device are estimated from the time of arrival (TOA) of the sound emitted by each device. The accurate estimation of TOAs in a real environment is also discussed. Experimental evaluations with iPod touch devices show that the proposed method works well even when the devices are placed several meters apart in a real environment.