Improving Resource Efficiency of PMCW-Based JCRS Systems: Simultaneous Transmission of Pilot and Data via Orthogonal Codes

Joint communications and radar sensing (JCRS) is regarded as a key application of the future 6G technologies. The phase-modulated continuous waveform (PMCW) has become popular for JCRS in recent years due to its strong anti-interference properties and low peak-to-average power ratio. Conventional PMCW systems suffer from several common problems, like low data rates and susceptibility to the Doppler effect. To address these shortcomings, this paper provides a novel PMCW approach that implements a parallel pilot and data transmission, where the pilot and data are divided by orthogonal codes. Compared to the conventional PMCW systems, the proposed method benefits from a flexible configuration of communications parameters and higher resource efficiency, improving communications performance while not influencing the radar function. Besides, the presented approach also reduces the impact of the Doppler effect on the reliability of communications. At last, the feasibility of this new method is verified, and its performance and application scenarios are analyzed.