Full-Duplex Integrated Sensing and Communication: Waveform Design and Performance Analysis

Integrated sensing and communication (ISAC) is a promising technology to fully utilize the precious spectrum and hardware in wireless systems. This paper studies ISAC for the important and challenging monostatic setup, where a dual-function radar-communication (DFRC) node wishes to simultaneously sense a radar target while communicating with a communication receiver. Different from most existing schemes that rely on either radar-centric half-duplex (HD) pulsed transmission with extremely low-rate information embedding, or communication-centric waveform with degraded sensing performance, we propose a novel full-duplex (FD) ISAC scheme that fully utilizes the waiting time in conventional pulsed radar to transmit dedicated communication signals. Compared to HD ISAC schemes, the proposed design can drastically increase the communication spectrum efficiency, and also improve the probability of target detection, as long as the self-interference (SI) is effectively suppressed. On the other hand, compared to communication-centric ISAC waveform, the proposed scheme is expected to have better auto-correlation property for sensing. Performance analysis in terms of the probability of detection for sensing and spectrum efficiency for communication is developed. Numerical results are provided to show the significant performance gain of our proposed design over benchmark schemes.