Designing the focused and wide beam pattern in linear and planar phased-MIMO radar considering the antennas' overlap

摘要

Phased-array multiple-input multiple-output (MIMO) radar is a new method for collocated MIMO radar, benefiting from its advantages without losing the coherent processing gain considered the main feature of phased-array radars. In this method, the whole array is divided into several overlapping subarrays; then a waveform is allocated to the antennas of each subarray, which are orthogonal to other subarray's waveforms. In order to obtain a desired beam pattern, appropriate weighting coefficients for each subarray should be designed. This study aimed to design the phased-MIMO radar's weighting coefficient matrix in two modes: In the first mode, the aim is to design a beam pattern, which has the maximum value in direction of the desired targets. In the second mode, a desired beam pattern is defined, and the coefficients should calculated in such a way that the obtained pattern be as much as possible compatible with the desired patter. In the two modes, the design, at first, is accomplished for linear array and then is extended to the planar array. Moreover, the impact of subarrays' overlap and the power constraints is investigated. The proposed methods, in special cases, are applicable in MIMO and phased-array radars, too.