A Study of High-Speed Railway Communication Channel Models for OTFS-Based Systems

Abstract

The fifth generation (5G) and beyond communication systems envisage use cases with high mobility. The transmitter and receiver moving at high speeds pose a challenge in acquiring channel state information because of deteriorating performance. The orthogonal time frequency space (OTFS) modulation provides solutions for high mobility scenarios with an aim to mitigate the effect of Doppler spread caused by the relative motion. In this study, we analyze the performance of OTFS modulation in high-mobility communication, specifically, in high-speed railways communication. We present an exhaustive comparison of channel models a railway system could face, including tunnels, rural and urban models. Through extensive simulations of standard 5G channel models, we also evaluate the error performance across different message recovery schemes. We show that the OTFS modulation is highly stable and remains relatively error-free even in adverse physical environments.