Geolocation by Direction of Arrival Using Arrays With Unknown Orientation

It takes a great deal of care to accurately align direction of arrival (DOA) sensors to a reference direction. Any error in alignment degrades the localization accuracy of the entire system. We propose a method that enables the alignment using DOA measurements of arbitrary sources. This saves the efforts to set and maintain the alignment by external means. To simplify the exhibition, it is assumed that the sensors and the sources are confined to a plane. The method is based on the maximum-likelihood estimator. The main challenge is the discontinuities in the cost function due to the circular nature of angle measurements. The proposed method is verified by simulations, and the performance is compared to lower bounds and also to systems with perfect alignment.