A Robust Waveform Design of MIMO Radars for Improving Detection Performance of Space-Time Adaptive Processing

A robust waveform design method of multi-input multi-output (MIMO)radars for improving the detection performance of space-time adaptive processing (STAP)is presented to focus the issue that the detection performance of the MIMO-OFDM radar based STAP method is heavily affected by the unascertained environmental prior knowledge. An estimation error model for clutter covariance matrix is firstly constructed. Then, with the constraints of this error model and waveform constant modulus, the waveform optimization issue to improve the robustness of the detection probability of STAP can be formulated, which is based on the criterion of maximizing the worst-case output signal-to-interference plus noise ratio (SINR). To solve the resultant nonlinear waveform optimization problem, an iterative approach based on diagonal loading is developed. Each step in the proposed iterative method can be recast as a semidefinite programming, and can be solved in an efficient way. Simulation results show that the proposed approach can improve the detection probability of STAP in the worst case, and in comparisons with the uncorrelated waveforms and the non-robust algorithm, the proposed method can improve the worst-case output of MIMO-OFDM-STAP SINR by 2 - 4 dB. © 2018, Editorial Office of Journal of Xi'an Jiaotong University. All right reserved.