Transmit Precoding for Dual-Function Radar-Communication Systems

As radio-frequency (RF) antenna, component and processing capabilities grow, the ability to conduct multiple RF system functions from a common aperture is being realized. Conducting both radar and communications functions from the same system is potentially useful for vehicular, health monitoring, and surveillance applications. This paper considers multiple-input-multiple-output (MIMO) dual-function radar communication (DFRC) systems in which the radar and communication modes use distinct baseband waveforms. A transmit precoder provides spatial multiplexing and power allocation among the radar and communication modes. Radar guarantee and communications guarantee optimization approaches for precoder design are developed based on a radar detection performance SINR metric. The methods guarantee a level of radar surveillance performance while maximizing communication system performance, or vice-versa. The methods are shown via simulation to enable high-performance in both modes with significant design flexibility, yielding improved detection performance and better approximation of desired ambiguity functions while satisfying communications objectives. Insights into precoder operation based upon system goals are also provided.