Blind Estimation of Locations and Time Offsets for Distributed Recording Devices

This paper presents a blind technique to estimate locations and recording time offsets of distributed recording devices from asynchronously recorded signals. In our method, locations of sound sources and recording devices, and the recording time offsets are estimated from observed time differences of arrivals (TDOAs) by decreasing the mean squared errors. The auxiliary-function-based updates guarantee the monotonic decrease of the objective function at each iteration. The TDOAs are estimated by the generalized cross correlation technique. The validity of our approach is shown by experiments in real environment, where locations of seven sound sources and eight microphones and eight time offsets were estimated from signals recorded by four stereo IC recorders in reverberant rooms.