Analysis and Propagation Modeling of Path Loss in THz Spectrum for Indoor Cognitive Scenarios

This paper presents a comparative analysis and propagation modeling of path loss (PL) in terahertz (THz) channels for indoor scenarios at 300 GHz. Experimental measurements in a conference room are used to evaluate several literature-based PL models by comparing their root-mean-square error performance. A custom-developed three-dimensional ray-launching simulation tool is introduced and validated against measurement data, yielding a mean absolute error of 0.77 dB. Furthermore, the study examines the impact of receiver height on PL characteristics by applying the Close-In PL model across multiple vertical levels of the conference room, revealing significant variations in the PL exponent and standard deviation. These findings underscore the need for height-specific channel models to support the design of robustTHz communication systems for next-generation networks.