The Price of Information in OFDM-DFRC Systems

This paper investigates the performance of a mutual information (MI)-optimal waveform for dual-function radar-communication (DFRC) orthogonal frequency-division multi-plexing (OFDM) systems. By design, the previously described waveform is random to account for the varying (i.e., information-bearing) transmitted symbols. From a radar perspective, we examine the sacrifices made in target estimation to transmit information and demonstrate that using phase-shift keying (PSK) symbols maintains performance as best as possible, unlike quadrature-amplitude modulation (QAM) or Gaussian symbols. As is well known, choosing a constellation to maximize the communication information rate follows an opposite recommendation, thus highlighting the radar-communication trade-off.