Two-dimensional spatial spectrum estimation by MIMO radar using part of the virtual aperture elements of the antenna array

A cost-effective algorithm for estimating the two-dimensional spatial spectrum using a MIMO antenna array is proposed. The elements of the virtual aperture are classified into two groups, where the first group corresponds to the location of the transmitting elements, and the second to the receiving ones. Two-dimensional spatial spectra are estimated for these groups, and a spatial spectrum corresponding to the entire virtual aperture is generated based on the results. Expressions are obtained that allow estimating the reduction in the number of mathematical operations required to calculate spatial spectrum references. Distortions of the two-dimensional spatial spectrum are evaluated during its estimation by the proposed algorithm. These distortions arise during observation of two or more objects differing only in angular coordinates. The ratios providing their compensation are obtained. The theoretical results are confirmed by mathematical modeling.