A Non-Uniform Multi-Wideband OFDM System for Terahertz Joint Communication and Sensing

Recently researchers have been attracted by the joint communication and sensing (JCS) techniques, due to their diverse benefits in communication-sensing applications. By sharing the spectrum and hardware components, the advantages of JCS systems include enhanced spectrum efficiency and reduced device costs. Following the trend of scaling up the carrier frequencies for 5G and beyond, Terahertz (THz) band is envisioned as a promising chunk of spectrum featuring multi-GHz bandwidth windows. However, despite the great promise, the waveform design for THz JCS is still not explored enough. In this work, the design guidelines for THz JCS waveform are presented. With the help of these guidelines, a non-uniform multi-wideband orthogonal frequency division multiplexing (NMW-OFDM) THz system is proposed to overcome the limitations of OFDM based JCS. The proposed NMW-OFDM system is able to realize sub-millimeter-level accuracy of the range estimation by using a multi-stage sensing algorithm, which is three orders of magnitude improvement compared to the OFDM-based JCS system. In addition, the accuracy of velocity estimation can be enhanced by 10 times within a short frame time. Finally, the system can achieve unprecedented communication data rate of 100 Gbps without sacrificing the maximum detectable distance.