Channel Characterization at Sub-THz Band with Measurements and Ray Tracing in Indoor Case

Ultra-wide bandwidth (BW) available at terahertz (THz) and sub-THz frequencies makes these bands interesting for wireless communication systems. A large BW at the sub-THz frequency band offers a promising solution for applications with short-range and high data rate requirements. Since the provision of high-speed computational systems, deterministic channel models have been extensively used for indoor field prediction and radio channel characterization, especially for high frequencies i.e., millimeter wave (mmWave) and sub-THz frequencies. We have developed an in-house built ray tracing (RT) tool, capable of characterizing a radio channel with good accuracy and precision. The aim of this paper is to validate the power angular spectrum (PAS) acquired through our RT tool with the measurement data at sub-THz frequencies of 90, 95, and 100 GHz, in both line-of-sight (LOS) and non-LOS (NLOS) University corridor environment. A photonics-based measurement setup with high accuracy is utilized for generating the sub-THz signal, and for acquiring the measurement data. In addition to the PAS, other channel metrics considered for the analysis through RT simulations are root mean square delay spread (RMS-DS) and RMS angular spread (RMS-AS) in an azimuth plane. The results presented in this paper show that our in-house built RT is capable of providing considerably good agreement between the measured and simulated PAS in both LOS and NLOS states.