Estimation of channel capacity in CAT6 cable with circular waveguide modeling for future THz communication systems

Millimeter-wave and terahertz (THz) frequency bands are being explored in wired and wireless communication systems due to ongoing demands for increased data rates. Recently, it has been proposed that twisted-pair cables, already part of existing infrastructure, could be utilized for terabit-per-second data transmission by exploiting wireless THz radiation between the copper wires. THz radiation can be wirelessly transferred through the dielectric gap and the air gap in between the copper wires. The air gap and the dielectric material between the copper wires in a CAT6 (Category 6) cable can be considered a circular hollow-core waveguide, providing a suitable medium for the propagation of THz waves. Therefore, this work aims to estimate the data rate per distance by experimentally analyzing the copper circular waveguide. Furthermore, the impact of a waveguide radius is also examined. Waveguide propagation characteristics were experimentally analyzed using THz time-domain spectroscopy as well as on a simulation basis using CST (Computer Simulation Technology) Microwave Studio 2022. It was found that the radius of the waveguide has a significant effect on the transmission characteristics of the waveguide and the channel capacity for a longer range. The proposed waveguides achieved a maximum data rate in Tbps (terabits per second) for a few meters depending upon the diameter of the waveguide. This study investigates the propagation of THz waves through narrower spaces and explores the initial steps toward realizing the concept of a TDSL (Terabit Digital Subscriber Line) and future high-frequency communication systems.