Direction of arrival estimation of unknown number of wideband signals in Unattended Ground Sensor Networks

Unattended Ground Sensor Networks (UGSN) are becoming increasingly popular for surveillance and situational awareness applications. Acoustic sensors can be used in UGSN to detect and to classify targets, and these sensors are cost efficient, easy to deploy, and above all, non-jammable since they are passive. An array of acoustic sensors can detect multiple sound sources and determine the direction of arrival (DOA), and the network can deal with the multi-sensor multi-target tracking. This contribution focuses on DOA estimation of wideband sources, such as vehicles. We develop a coherent DOA estimation method by taking advantage of the spatial sparsity of the wideband acoustic sources as a prior information, as an extension to the recently proposed SPICE method for narrowband sources. The method has been tested on both simulated data and field test data with different vehicles with very good performance compared to other state of the art methods.