Comprehensive Link-Level Simulator for Terahertz MIMO Integrated Sensing and Communication Systems With TDD Framework

Terahertz (THz) integrated sensing and communication (ISAC) with multiple-input multiple-output (MIMO) architecture is recognized as a promising interdisciplinary technology for ultra-high-rate mobile communications since the systems enable narrow beam tracking which is necessary in the THz band. In this work, a link-level simulator for THz MIMO ISAC in time-division duplex (TDD) operation is proposed to design and analyze mobile systems. Compared to the simulators in the literature, the proposed simulator is more practical and comprehensive, employing two-dimensional position and motion simulation to develop localization capabilities, and considering THz characteristics such as wideband echo, molecular absorption and cluster-based channel. Specifically, the simulator supports the standard orthogonal frequency division multiplexing (OFDM) and discrete Fourier transform spread OFDM (DFT-s-OFDM) waveforms for sensing and communication simultaneously. Trade-offs between communication and sensing metrics required for waveform numerology design are investigated. In particular, by exploiting TDD framework's integration capability, range-velocity-angle estimation with virtual array and sensing-aided downlink spatial multiplexing are co-designed. Additionally, a user interface with elaborate parameter configuration is introduced. Finally, we implement an urban vehicle-to-vehicle (V2V) application case to verify the simulator. The simulation results present the feasibility of the developed integrated architecture.

I. Introduction

The terahertz (THz) band (0.1–10 THz), the last unutilized piece of radio-frequency (RF) spectrum [1], where hundreds of GHz bandwidth is available to facilitate wireless transmission of terabit-per-second (Tbps) rates, is recognized as one of the candidate bands and key technologies for the sixth generation (6G) of mobile communication systems by academia and industry worldwide [2], [3]. Aiming to realize the comprehensive interconnection of man-machine-thing in 6G, THz integrated sensing and communication (ISAC) has been promoted recently [4].