Communication-Assisted Chirp Sequence Radar With Improved Data Rate

This letter presents a novel communication-assisted chirp sequence radar (CaCSR) system with an improved communication data rate, where part of each chirp is modulated with communication symbols. The transmit signal is partially modulated by one of the digital constellation schemes, such as phase-shift keying. Extending a previous study, which investigated the general idea of the partial modulation at 4 GHz under AWGN scenarios, this letter analyzes the channel effect on the CaCSR communication performance and presents results from measurement at 79 GHz. For this purpose, the number of assigned communication symbols is compared with the channel length, the duration of the communication section, and the pause between the chirps, where the communication receiver comprises a direct architecture with a small fraction of the whole radar bandwidth. Finally, the performance of the proposed system is verified via simulation and measurement results, showing that it achieves superior communication performance compared with a reference method where only one modulation symbol is transmitted per chirp at the cost of negligible radar performance degradation.