OTFS Waveform Design Based on WFRFT for Integrated Sensing and Communication

As an emerging technology that integrates radar and communication functions, the integrated sensing and communication (ISAC) is regarded as the key to future mobile communication requirements. In this paper, we propose an ISAC framework based on weighted-type fractional Fourier transform orthogonal time frequency space (WFRFT-OTFS) waveform, which can flexibly adjust parameters to optimize communication and sensing performances jointly. Additionally, the sensing features of WFRFT-OTFS waveform are deeply investigated for different weighting orders. Furthermore, peak-to-average power ratio (PAPR) and out-of-band power (OOBP) of WFRFT-OTFS waveform are suppressed through a combined windowing and selected mapping algorithm, which is positive for waveform design in ISAC systems.

I. Introduction

In next-generation mobile communication technologies, it is expected that higher frequency bands, more unified waveforms, and larger-scale antenna arrays could be used jointly to make communication systems have similar working spectrum and hardware structures to those in sensing systems. With the development of cognitive radio technology, it is possible to achieve the integration between sensing and communication systems in terms of waveforms and baseband digital signal processing. As a result, integrated sensing and communication (ISAC) systems have attracted the attention of many researchers.