Interference Self-Cancellation Based Low-Complexity OTFS for High-Mobility Coverage

Abstract

Orthogonal Time-Frequency-Space (OTFS) modulation has demonstrated superior performances to extend coverage for high-mobility communicatoins. In this paper, we propose a novel OTFS scheme featuring interference self-cancellation achievable with nearly linear complexity. We first apply the repetitive precoding in delay-Doppler domain, and performing negative padding in the time-frequency domain. Additionally, we formulate equivalent coefficients for the TF domain channel to obtain combined gain with point division equalization. Through numerical simulation, compared with the unprocessed OTFS system, the proposed scheme can achieve a significant performance improvement under TF domain point equalization. Finally, through the analysis of computational complexity, our proposed scheme can realize the transceivers design and equalization with approximately linear complexity.