Performance Analysis of Tera Hertz Frequencies on Intelligent Reflecting Surfaces for 6G Communications

The rapid advancements toward 6G networks have powered interest in the terahertz (THz) frequency band due to its potential for delivering ultra-high data rates. It provides massive connectivity. However, THz communication faces significant challenges. It includes high path loss, molecular absorption and blockage sensitivity. These are severely degrading signal quality over distance. Intelligent reflecting surfaces (IRS) emerged as a promising solution to address these issues. IRSs reflect and direct signals to desired locations. This improves communication quality. It does not require extra power sources. In this study, we look at how different factors affect performance. These factors include the distance between the transmitter and IRS, transmit power, number of IRS elements, LoS/NLoS path-loss ratio, number of transmit antennas and frequency in the THz band. We find the best configurations for IRS-aided THz systems. Using pathloss and channel models, measure spectral efficiency and achievable rate. This helps identify key factors for improving system efficiency and reliability. Using more IRS elements improves signal quality and data rates. With every 100 added elements (up to 700), data rates increase by 20–30%. After 700 elements, the improvements become smaller. This shows the need to choose a balanced IRS size for best performance. The results show that the distance between the transmitter and IRS affects spectral efficiency. Closer IRS placements improve efficiency.