PAPR Reduction in OTFS Based FrFT-OFDM Systems

Orthogonal Time Frequency Space (OTFS) modulation has gained significant attention in the field of wireless communications, owing to its ability to establish robust connections in high-speed applications. By operating in the Delay-Doppler (DD) domain, OTFS achieves channel invariance, thereby enhancing its resilience. Moreover, integrating OTFS into an existing Orthogonal Frequency Division Multiplexing (OFDM) system can result in reduced installation costs. Previous studies have demonstrated that Fractional Fourier Transform (FrFT)-based OFDM surpasses conventional OFDM in terms of Peak-to-Average Power Ratio (PAPR) mitigation. In this paper we compared the PAPR performance of OTFS with classic Fast Fourier Transform (FFT) and OTFS with FrFT. Our simulation results indicate a 3 dB PAPR reduction when using OTFS with FrFT, as compared to OTFS with classic FFT.