Intelligent-Reflecting-Surface-Empowered Terahertz Wireless Communication: System Modeling and Performance Analysis

Terahertz (THz) wireless communication has emerged as a front-line technology for substantially improving the data rates for 6G networks. However, they suffer from tremendous path-attenuation that limits the communication distance. Intelligent reflecting surface (IRS) is an excellent cost-effective technology for enabling THz wireless systems. This article presents comprehensive analysis of an IRS-empowered THz system, incorporating a detailed channel model encompassing deterministic IRS channel gain, THz molecular absorption losses, and the characteristics of sum of double $\alpha -\mu $ fading. The analysis considers IRS-specific parameters, such as unit-cell dimensions, gain, radiation pattern, and array factor, for accurate received signal power characterization. For statistical analysis, the probability density function, cumulative distribution function, and moments are characterized using programmable multivariate Fox’s H-functions. Using these derived statistical results, the exact closed-form solutions for outage probability, average bit error rate, and ergodic capacity are reported. Additionally, asymptotic approximations are presented for deeper insights. Finally, to validate the accuracy of analytical results, extensive Monte-Carlo simulations are conducted. Multiple results investigate various design aspects of the proposed system. The findings demonstrate that significant performance gains and power savings thereby making THz communication feasible and highly promising for future wireless networks.