DOA Estimation for Monostatic Coprime MIMO Radar With Mixed-Resolution Quantization

In this correspondence, we address the issue of direction-of-arrival (DOA) estimation for coprime multiple-input multiple-output (MIMO) radar employing mixed-resolution quantization. First, we derive the received signal model of coprime MIMO radar under mixed-resolution quantization, and utilize mixed-resolution measurements to construct an augmented signal vector via virtual array interpolation. Subsequently, we reconstruct a low-rank augmented covariance matrix without the effect of quantization error by solving an atomic norm minimization problem. Finally, we extract the DOAs of targets by applying MUSIC method on the reconstructed low-rank matrix. Unlike the existing techniques, our method not only recovers the missing correlation information, but also reduces the influence of noise and quantization error. Simulation results illustrate the advantage of the proposed approach over the existing techniques when handling mixed-resolution measurements.