Channel Characterization and Capacity Analysis for THz Communication Enabled Smart Rail Mobility

As a vital vertical industry empowered by the sixth-generation mobile communication system (6G), the vision of “smart rail mobility” requires a seamless wireless connectivity with the ultra high-data rate on the order of 100 Gbps or even more. This forms a strong driving force for exploiting the terahertz (THz) band where the available spectrum is massively abundant. In this paper, the smart rail mobility channel is characterized through ultra-wideband (UWB) channel sounding and ray tracing (RT) at 300 GHz band with an 8 GHz bandwidth in the five scenarios - Train-to-infrastructure (T2I), Inside station, Train-to-train (T2T), Infrastructure-to-infrastructure (I2I), and Intra-wagon. Corresponding channel characteristics such as path loss, shadow fading, Rician K-factor, root-mean-square delay spread, azimuth/elevation angular spread of arrival/departure, and cross-polarization ratio are extracted and analyzed. Based on realistic channel information, the performance of THz communication is investigated in terms of channel capacity for all above five scenarios with various antenna patterns and weather conditions (except Intra-wagon) - sunny, rainy, and snowy. The results provide valuable insights into the system design and evaluation for THz communication enabled Smart Rail Mobility.