A survey on orthogonal time frequency space modulation

Orthogonal time frequency space (OTFS) modulation is strongly considered a promising solution for high-mobility communications. In contrast to conventional modulation techniques, wherein information symbols are multiplexed in one-dimensional time or frequency domain, OTFS employs a two-dimensional modulation scheme by multiplexing information symbols in the Doppler-delay domain. This paper presents a comprehensive survey of OTFS. It starts with an overview of OTFS, its advantages over conventional air interference techniques, general block diagrams, and implementations. Subsequently, the paper explores the potential integration of multiple-input multiple-output (MIMO) and OTFS techniques. The paper further discusses the feasibility of integrating OTFS into multiple access techniques as a solution for maintaining acceptable performance in high-mobility scenarios. Then, widespread applications of OTFS in satellite communications are highlighted. The paper concludes by pointing out numerous challenging and promising directions for future OTFS research.

Mots clés

Orthogonal time frequency space (OTFS); delay-Doppler domain; multiple-input multiple-output; multiple access techniques; satellite communications; integrated sensing and communications; deep learning; index modulation; underwater acoustic; unmanned aerial vehicle