Joint range and angle estimation with coprime FDA-MIMO radar

This paper deals with the problem of joint angle and range estimation for multiple targets in a Coprime frequency diverse array multiple-input multiple-output (FDA-MIMO) radar. At the design stage, a coprime array is utilized for both transmission and reception, where coprime frequency offsets are introduced in the transmit array elements. In order to obtain the range and angle information of the targets, the estimation problem is formulated resorting to the Maximum Likelihood (ML) criterion. Hence, a Linearized Array Manifold (LAM) method is developed by performing a tailored linearization of the array steering matrix around the nominal angles and ranges, where the array steering matrix is approximated at the first order. At the analysis stage, the Cramér-Rao Bound is derived, and the performance of the proposed method is assessed in terms of Root Mean Square Error (RMSE), where comparisons among other counterparts are carried out. Numerical results corroborate the effectiveness of the considered strategy in the background of Gaussian noise.