A review on direction finding in partly calibrated arrays

It is known that sensor arrays in certain practical applications may be incompletely calibrated. As a result, the response of some sensor elements is poorly known or even unknown. This class of arrays is usually referred to as partly calibrated arrays. During the past several years, the problem of direction finding in partly calibrated arrays has received great research interest. This paper aims to provide a timely review on this area. Several classical and recently developed direction finding algorithms for this kind of arrays, such as rank-reduction (RARE) estimator and ESPRIT-like method, are presented. As a conclusion, a brief discussion on the existing methods are given and the open research problems on direction finding in partly calibrated arrays are outlined for reference purposes.