OTFS: A Review on High-Mobility Modulation Scheme for 6G or Beyond

Orthogonal Time Frequency Space (OTFS) modulation is a revolutionary 2D modulation scheme that revolutionized the field of wireless communications by leveraging Delay-Doppler components. Unlike conventional modulation techniques such as TDMA (Time Division Multiple Access), CDMA (Code Division Multiple Access) and OFDM (Orthogonal Frequency Division Multiplexing), OTFS offers matchless advantages, particularly over environments characterized by high-frequency dispersion. Such environments exhibit increased phase noise, and significant doppler spread which deteriorates the performance exponentially. The paper presents a comprehensive overview of OTFS modulation, highlighting its strengths and limitations. The versatility of the modulation scheme finds application across diverse domains of next-generation networks, including high-speed mobility scenarios such as railway, vehicular and drone communication. By exploring the basic principles of OTFS, the paper demonstrates its remarkable ability to address challenges posed by real-world time varying channels. With high resilience and adaptability, OTFS appears to be a promising technology for next-generation communication.