Efficient Joint Broadband Radar and Single Carrier Communication System in Frequency Division Multiplexing for High-Range Applications

Real-time, high-resolution radar measurements resulting from a system bandwidth of several GHz are important for many applications nowadays. Additionally, wireless data transmission of system - and scenario information with low rate plays an important role in such sensor systems. Therefore, it makes sense, especially for military applications such as synthetic aperture radar, to integrate a communication link into such a broadband radar system e.g. for friend-foe-identification. This publication describes the investigation of an efficient dual function system for broadband FMCW radar and single-carrier QPSK communication in frequency division multiplexing (FDM) for high-range applications. The transceiver architecture combines a 35 GHz FMCW radar with 2 GHz bandwidth and a QPSK modulator centered at 37.4 GHz with a data rate of 0.2 Mbit/s in FDM mode. The investigation of the influence of the radar chirp to the communication receiver and the QPSK-signal to the radar measurement is presented. The successful operation of an efficient joint broadband FMCW radar and single-carrier QPSK communications system for high-range applications is shown for a peak-to-average power ratio of theoretically 6 dB and a maximum bandwidth of 3.4 GHz of the transmit signal.