A Novel Low-PAPR Integrated Navigation-Communication Waveform Design for LEO Satellite Systems

Current orthogonal frequency-division multiplexing (OFDM)-based integrated navigation-communication (INC) designs suffer from critical limitations, particularly high peak-to-average power ratio (PAPR), which ultimately compromises the performance of both communication throughput and positioning accuracy. This paper proposes an acquisition-assisted low PAPR INC signal design scheme. Specifically, the transmitter utilizes the selectivity of the pseudorandom sequence designed for the navigation function in the frame header to indicate the index of the phase sequence that minimizes the PAPR of the OFDM signal, thereby avoiding the transmission of side information (SI) and achieving a reduction in PAPR. The receiver leverages the correlation properties of the designed synchronization sequence to jointly recover SI and estimate Doppler shift and time delay during the acquisition phase. The computational complexity of the proposed scheme is analyzed for both signal generation and SI recovery processes. The simulation results demonstrate that the proposed INC scheme achieves significant PAPR reduction without causing a degradation in the bit error rate (BER), maintains robust detection probability in low signal-to-noise ratio (SNR) environments, and attains high acquisition accuracy.