Abstract: One of the key aspects of a multiple-input multiple-output(MIMO) radar system is its array design. Because of the augmented phase centers of transmitter and receiver, the resolution and degrees of freedom can be improved. This article commences with signal model, and discusses the equivalent array of orthogonal signals. The principles and methods of the MIMO array design are proposed aimed at the estimation of direction of arrival (DOA). Exclusivity and rationality of the combination of transmitter-receiver array are obtained through parabola theories. Then optimum interelement spacing of transmitter array is given by analyzing different combinations of the transmitter-receiver array. An optimal analytical solution of the array design under some conditions is also given, and the simulation is carried out. The effectiveness of the method is verified by simulation results.

Key words: MIMO radar, antenna array, direction of arrival, orthogonal signals, array signal processing