Performance bounds for an OFDM-based joint radar and communications system

We investigate a joint radar and communications performance bound for a single pair of bistatic transmit and receive antennas that uses orthogonal frequency-division multiplexing (OFDM) transmission. The OFDM transmission signal is designed to simultaneously meet radar target detection and communications signal recovery objectives using training and information symbols on different subcarriers. Given a frequency-selective Rayleigh-distributed fading channel, equally powered and equally spaced training symbols across the occupied bandwidth minimize the mean-square error of the channel estimate, which is tied to a lower bound on ergodic channel capacity. We perform a hypothesis test on the resulting channel estimate to detect and locate targets. We examine the performance region of capacity versus probability of detection in an example scenario in which a single stationary target is present.