A Generalized Statistical Model for THz wireless Channel with Random Atmospheric Absorption

TL;DR

This paper introduces a comprehensive statistical model for THz wireless channels that accounts for random atmospheric absorption, fading, and hardware impairments, applicable to diverse environments and enabling detailed performance analysis.

Contribution

It develops a unified model incorporating random absorption, complex fading, and hardware effects using Fox's H-functions, extending prior models focused mainly on sub-THz bands.

Findings

The model accurately captures the combined effects of atmospheric absorption and fading.

Analytical expressions for outage probability are derived.

Simulations validate the model's effectiveness across various scenarios.

Abstract

Current statistical channel models for Terahertz (THz) wireless communication primarily concentrate on the sub-THz band, mostly with $\alpha$-$\mu$ and Gaussian mixture fading distributions for short-term fading and deterministic modeling for atmospheric absorption. In this paper, we develop a generalized statistical model for signal propagation at THz frequencies considering random path-loss employing Gamma distribution for the molecular absorption coefficient, short-term fading characterized by the $\alpha$-$\eta$-$\kappa$-$\mu$ distribution, antenna misalignment errors, and transceiver hardware impairments. The proposed model can handle various propagation scenarios, including indoor and outdoor environments, backhaul/fronthaul situations, and complex urban settings. Using Fox's H-functions, we present the probability density function (PDF) and cumulative distribution function (CDF) that capture the combined statistical effects of channel impairments. We analyze the outage probability of a THz link to demonstrate the analytical tractability of the proposed generalized model. We present computer simulations to demonstrate the efficacy of the proposed model for performance assessment with the statistical effect of atmospheric absorption.