Coverage Analysis for 3D Terahertz Communication Systems

TL;DR

This paper provides a novel 3D coverage probability analysis for terahertz communication systems, considering unique propagation effects, directional antennas, and blockage, offering insights into system reliability and design improvements.

Contribution

It introduces a comprehensive analytical framework for 3D THz coverage analysis that accounts for vertical heights, directional antennas, and various blockages, which was not addressed in prior work.

Findings

Ignoring vertical heights underestimates coverage probability.

Increasing AP antenna directivity improves system reliability.

Blockage effects significantly impact coverage performance.

Abstract

We conduct novel coverage probability analysis of downlink transmission in a three-dimensional (3D) terahertz (THz) communication (THzCom) system. In this system, we address the unique propagation properties in THz band, e.g., absorption loss, super-narrow directional beams, and high vulnerability towards blockage, which are fundamentally different from those at lower frequencies. Different from existing studies, we characterize the performance while considering the effect of 3D directional antennas at both access points (APs) and user equipments (UEs), and the joint impact of the blockage caused by the user itself, moving humans, and wall blockers in a 3D environment. Under such consideration, we develop a tractable analytical framework to derive a new expression for the coverage probability by examining the regions where dominant interferers (i.e., those can cause outage by themselves) can exist, and the average number of interferers existing in these regions. Aided by numerical results, we validate our analysis and reveal that ignoring the impact of the vertical heights of THz devices in the analysis leads to a substantial underestimation of the coverage probability. We also show that it is more worthwhile to increase the antenna directivity at the APs than at the UEs, to produce a more reliable THzCom system.