Waveform Design for Dual-functional Radar and Communication Design Based on Conditional MI

In this paper, we consider optimal designs for dual functional radar and communication (DFRC) system with multiple-input multiple-output (MIMO) antennas for a single user and multi users, respectively. We consider a time division duplexing (TDD) scheme, which splits duration into two parts including communication symbols and radar waveform. We first formulate the mutual information (MI) both for radar sensing and communication. Then we give the optimal design for communication transmit filter and radar waveform through maximizing weighted-sum MI for a single user. We present the model for multi communication users in DFRC system and propose an algorithm based on weighted minimum mean-square error (WMMSE) to optimize the weighted MI alternatively, then the waveform and transmit filters are given for multi-user scenario. Numerical results validate the effectiveness of the proposed designs.