Direction finding using minimum redundancy MIMO radar

An augmented covariance matrix, which has the characteristics of Hermitian and Toeplitz, is constructed for minimum redundancy (MR) multiple-input multiple-output (MIMO) radar to implement direction finding using Capon algorithm. A diagonal loading technique is employed to avoid non-positive definite of the covariance matrix. The diagonal loading level is adjusted adaptively according to the eigenvalues of the covariance matrix. The proposed method not only expands the system degrees-of-freedom (DOFs), but also has robust spatial spectrum estimation performance. In addition, the method requires no priori knowledge of the number of targets. Simulation results showing the performance improvement of the proposed method is presented.