Performance Analysis of Hybrid FSO/RF-THz Relay Communication System

Abstract

In the connection between the last kilometer access network and the backbone network, the dual-hop hybrid freespace optical/radio frequency(FSO/RF) relay system is considered to be an effective solution to increase the capacity and coverage of the wireless communication system. However, the transmission performance of FSO link is greatly affected by atmospheric turbulence, pointing errors and weather such as fog and snow, and the RF access network has low rate and relatively high delay. To ensure communication quality, a hybrid FSO/RFterahertz(THz) relay system has been designed. Decode-andforward relay is selected, and the hybrid FSO/RF communication based on adaptive combining scheme is considered before the relay node, and THz link is used after the relay node to access the users. Using the statistical characteristics of different links obtained, expressions for the outage probability and average bit error rate of the system were derived. The effects of different parameters on the performance of hybrid FSO/RF-THz relay system is studied, and the first hop adaptive combining scheme is compared with the single-threshold switching scheme and the single-link FSO system. The analysis results indicate that the hybrid FSO/RF-THz relay system can provide better outage and bit error rate performance by using the adaptive combining scheme, which can improve the system communication rate while taking into account the communication reliability.

Unmanned Aerial Vehicle-Assisted Terahertz–Visible Light Communication Systems: An In-Depth Performance Analysis

“…However, THz communication also presents challenges, such as a limited transmission range and significant atmospheric attenuation. To overcome these obstacles, research is focused on developing advanced materials, innovative antenna designs, sophisticated signal processing techniques, and the use of mobile base stations [5,6].…”

“…In terms of THz, similar to VLC, several studies have been conducted that combine it with either RF or FSO [13,14]. Some studies have been conducted on performance improvement that combine all three of them into one system; for example, in [6], the authors propose a hybrid FSO/RF-THz DF relay link. Here, an adaptive combiningbased approach is used for the backhaul network by combining FSO and RF, and then, through the DF relay, the end user receives the information using a THz link.…”