Dual-use baseband signal design for RadCom with position index and phase modulation

This paper deals with the synthesis of dual-use signal to simultaneously achieve detection and com-munication for a dual-function radar communication (DFRC) system. A new position index and phase (PIP) modulation is proposed for information embedding, where position index modulation is realized by selecting the information embedding subpulses (InSp) positions. Moreover, differential phase mod-ulation is utilized to distinguish InSp from other available subpulses. As for radar detectability, peak sidelobes level (PSL) of signal auto-correlation function is minimized. Meanwhile, constant-envelope and phases constraints are forced to ensure compatibility with the current hardware technique and mod-ulation demand, respectively. To tackle the resulting nonconvex and NP-hard optimization problem, a spectral majorization-minimization (SM) dual-use baseband signal design method is proposed. In each it-eration, the original problem is approximated by a tractable problem with a closed-form solution. Finally, simulation and semi-physical experimental results demonstrate the designed dual-use signal is capable of realizing high data rate communication and ensuring acceptable radar performance.(c) 2023 Elsevier B.V. All rights reserved.