Non-coherent PSK-based dual-function radar-communication systems

Dual-function radar-communication (DFRC) systems enable information embedding into the radar signal emission. Existing methods for non-coherent phase-modulation DFRC employ multiple pairs of orthogonal waveforms and embed one communication symbol into each pair. The total number of symbols is equal to one-half of the number of waveforms. In this paper, we propose a new signaling strategy for embedding a higher number of communication symbols. The proposed method implements non-coherent phase-shift keying (PSK) by employing one of the orthogonal waveforms as a common reference and modulating the information in terms of the phase differences between all other waveforms and the reference waveform. The number of communication symbols that can be embedded equals the total number of waveforms minus one. We introduce two schemes for achieving a desired phase constellation. The proposed approach is shown to achieve a two-fold increase in the data rate compared to existing methods for a large number of waveforms.