A Nyström-Based Low-Complexity Algorithm with Improved Effective Array Aperture for Coherent DOA Estimation in Monostatic MIMO Radar

In this paper, we propose a computationally efficient algorithm with improved effective aperture for coherent angle estimation in monostatic multiple-input multiple-output (MIMO) radar. First, the direction matrix of MIMO radar is mapped into low-dimensional virtual uniform linear array (ULA). Then, an augmented data expansion obtained by exploiting Vandermonde-like structure and cross section (RCS) to enlarge array. Next, unitary transformation used transform real value approximate signal subspace Nyström method, which can reduce computational complexity. The eigenvectors are reconstruct direct decorrelation processing. Finally, arrivals (DOAs) be estimated faster utilizing ESPRIT since rotation invariance extended reconstruction still exists. proposed has lower total complexity, accuracy values enlarging estimation. Several theoretical analyses simulation results confirm effectiveness advantages method.