MIMO Radar Waveform Design for Multipath Exploitation
Zhou Xu, Chongyi Fan, Xiaotao Huang
Abstract
This paper considers specular reflection multipath exploitation by jointly designing the transmit waveform and receive filter for a colocated multiple-input-multiple-output (MIMO) radar system. The goal is to maximize the output signal-to-interference-pulse-noise ratio (SINR) at the receiver with a constant modulus constraint (CMC) on the transmit waveform. Assuming the multipath information to be known or partially known, we consider the waveform-filter design under two different cases. In the first case, the multipath information is exactly known. We devise <bold xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Algorithm 1</b> to optimize the transmit waveform and receive filter alternatively. In the second case, the phase information of multipath reflection is unavailable. Under this situation, the minimax or robust waveform-filter design model is established; i.e., we maximize the worst-case SINR against the phase uncertainties. <bold xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Algorithm 2</b> is proposed to solve the corresponding minimax optimization problem through alternating iterations. At each iteration, the closed form of optimal receive filter is derived, and waveform optimization is converted to a convex optimization problem through semi-definite relaxation (SDR). Finally, numerical experiments are carried out to verify the effectiveness of the proposed algorithms. The Results demonstrate the superiority of the designed waveform-filter pair compared with some existing solutions.