Coordinate-based direction-of-arrival estimation method using distributed microphones

In this paper, we propose a new coordinate-based di-rection-of-arrival (DOA) estimation method, which is applied to several distributed security cameras that have a single microphone each. The proposed method tries to specify the location coordinate of each sound source at regular intervals. To this end, the time differences between multi-channel microphones are first estimated by applying the generalized cross-correlation with phase transform (GCC-PHAT) algorithm to the signals recorded in each pair of microphones. Then, a support vector machine (SVM) is used to classify whether each sound source is located at a closed area constructed by the microphone array. Next, the location of the sound source is estimated as the point at which there is a minimum error between the estimated time difference from the recorded signal to each pair of microphones and the time difference at the specified coordinates using GCC-PHAT. A performance evaluation shows that the classification accuracy of the SVM is 98% and the average distance error is within 10cm.