Evaluation of Interference between 300 GHz Band Fronthaul Links Using Measured High Gain Antenna Radiation Patterns

To shorten the distance between base stations (BSs) and user terminals, next-generation mobile communications (6G) plans to install large numbers of remote antenna units (RAUs) on traffic signals and street lights and connect these RAUs to base band units (BBUs) on buildings using terahertz (THz) band fronthaul radio lines capable of data rates that exceed 100 Gbit/s. However, when THz band fronthaul wireless circuits are densely deployed in urban areas, the challenge is to maintain line-of-sight (LOS) between RAUs and BBUs and prevent interference between fronthaul wireless links. In this study, the three-dimensional (3D) radiation pattern of a 300-GHz-band high-gain antenna was measured using the near-field-to-far-field (NF-FF) conversion method, and the accuracy was compared with the far-field measurement results. Moreover, an algorithm for automatically deploying a 300-GHz-band wireless fronthaul link is proposed, which can be used to position BBUs in locations where one BBU can be connected to as many RAUs as possible. Propagation simulations for fronthaul wireless links placed by the automatic deployment algorithm, using the measured 3D radiation patterns from high-gain antennas, show no interference between the fronthaul wireless links.