A Dual-Functional Affine Frequency Division Multiplexing Waveform for ISAC Systems: Design and Optimization

Abstract

As one of the novel waveforms recently proposed for future wireless communications, affine frequency division multiplexing (AFDM) is capable of combating the effects of Doppler shifts and its superiority over the widely used orthogonal frequency division multiplexing (OFDM) in high-mobility scenarios has been demonstrated. However, for the same amplitude and phase modulation (APM) order, the peak-to-average power ratio (PAPR) of AFDM signals is much higher than that of OFDM signals, which hinders their practical applications. In this paper, we propose an iterative majorization-minimization (MM)-based scheme to reduce the PAPR of AFDM signals for the application of integrated sensing and communication (ISAC). Simulation results show that the proposed scheme can effectively reduce the PAPR of AFDM signals, while still maintaining the good autocorrelation property of low sidelobe levels for sensing.