A Dual Channel MAC Protocol with IRS Relay Selection Mechanism for Terahertz Communication

The demand for high-speed data transmission in 6G networks has triggered the urgent need for research on terahertz (THz) communication frequency bands. However, the THz directional transmission and rapid attenuation in the air pose a challenge to the design of Medium Access Control (MAC) protocols. In this paper, a novel Terahertz Dual Channel MAC Protocol based on IRS Relay Selection (RS-MAC) is proposed, which leverages GHz frequency band for control signaling and employs THz beams for data transmission. Firstly, we introduce a Joint Judging Line-of-Sight (LoS) Algorithm Based on Location and Angle Information (LA-LoS) to determine whether LoS exist between the transmitter and receiver. Moreover, we capitalize on the unique reflection characteristics of Intelligent Reflection Surface (IRS) technology to introduce IRS relay paths at the MAC layer, reducing relay delay and enhancing data transmission efficiency. In the end, numerical simulations were conducted to analyze the performance improvements. The results indicate that, compared with some existing MAC relay protocols, the proposed protocol exhibits a substantial reduction in THz transmission delay and an improvement in achievable throughput.