Target Detection for Reconfigurable Intelligent Surface Assisted MIMO Radar

In this paper, we investigate the problem of target detection in the reconfigurable intelligent surface (RIS)-assisted multiple-input multiple-output (MIMO) radar system. Firstly, we propose a general signal model adapted to the RIS-assisted MIMO radar, where the RIS is far-field deployed, and orthogonal waveforms are employed by the MIMO radar. Based on the signal model, a non-coherent detection scheme that requires no phase synchronization and is relatively easy to be implemented, and a coherent detection scheme that obtains a detection performance gain by exploiting the phase information, are proposed. Furthermore, we analyze the detection probability and false alarm probability of proposed detection schemes, and optimization algorithms for the phase shift settings of the RIS elements are formulated using the Neyman-Pearson criterion. Simulation results demonstrate that the RIS-assisted MIMO radar outperforms the traditional MIMO radar.