Joint OFDM Waveform Design for Communications and Sensing Convergence
Sahan Damith Liyanaarachchi, Carlos Baquero Barneto, Taneli Riihonen, Mikko Valkama
Abstract
This paper discusses waveform design for a joint radar and communication system, where the radar transceiver and the communication transmitter are considered to be the same full-duplex base station. The downlink orthogonal frequency-division multiplexing (OFDM) waveform of the communication system is used also for sensing. Thus, unused subcarriers within the OFDM symbols are exploited for radar purposes and filled up with optimized complex-valued data, so as to minimize the lower bounds of the variances of the delay and Doppler estimates of radar target parameters, while maintaining an acceptable level of performance for the communication system. The results indicate that significant improvements can be made for the radar system, but in compensation, the power allocated for the communication subcarriers needs to be reduced. Thus, a trade-off between the converged systems allows both to operate together with reduced performance degradation.