DOA Estimation for Coprime Array via Capon-MUSIC Algorithm

In the field of direction-of-arrival (DOA) estimation, coprime array is a new type of array rising in recent years. It significantly improves the degree of freedom (DOF), cope with scenarios when the number of sources is larger than that of array elements compared with traditional uniform linear array (ULA). In this paper we study the DOA estimation method based on multiple-input multiple-output (MIMO) radar with coprime array, build the coprime array signal model, obtain the steering vector of the virtual array and calculate the coprime array signal covariance matrix which can be disposed by Capon and multiple signal classification (MUSIC) algorithm. We develop the Capon-MUSIC algorithm to deal with situations when the target number is unknown. Compared with the ULA with equal array elements, simulation experiments verify the superiority of DOA estimation performance of coprime array.