Table of Links I. Abstract and Introduction
II. Related Work
III. Modeling of Mobile Channels
IV. Channel Discretization
V. Channel Interpolation and Extrapolation
VI. Numerical Evaluations
VII. Conclusions, Appendix, and References I. Abstract and Introduction I. Abstract and Introduction II. Related Work II. Related Work III. Modeling of Mobile Channels III. Modeling of Mobile Channels IV. Channel Discretization IV. Channel Discretization V. Channel Interpolation and Extrapolation V. Channel Interpolation and Extrapolation VI. Numerical Evaluations VI. Numerical Evaluations VII. Conclusions, Appendix, and References VII. Conclusions, Appendix, and References VII. CONCLUSIONS In this paper, we talked about the advantages of OTFS over OFDM in terms of spectral efficiency, resulting from the much reduced channel training overhead. We showed that the D-D domain channel model is also an approximation of the real channel, but it is more accurate then the LTI model, and thus allows us to estimate the channel with a much reduced channel estimation frequency. The predictability of the channel in T-F domain comes from the sparsity of response in D-D domain. 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Grochenig, “Foundations of time-frequency analysis,” in ¨ Applied and Numerical Harmonic Analysis, 2000. [47] Z. Gong, “Fast signal interpolation through zero-padding and FFT/IFFT.” arXiv:2407.06502 [eess.SP], 2024. Authors:
(1) Zijun Gong, Member, IEEE;
(2) Fan Jiang, Member, IEEE;
(3) Yuhui Song, Student Member, IEEE;
(4) Cheng Li, Senior Member, IEEE;
(5) Xiaofeng Tao, Senior Member, IEEE. Authors: Authors: (1) Zijun Gong, Member, IEEE; (2) Fan Jiang, Member, IEEE; (3) Yuhui Song, Student Member, IEEE; (4) Cheng Li, Senior Member, IEEE; (5) Xiaofeng Tao, Senior Member, IEEE. This paper is available on arxiv under CC BY-NC-ND 4.0 license. This paper is available on arxiv under CC BY-NC-ND 4.0 license. available on arxiv

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Study Highlights Why OTFS Outperforms OFDM in Doubly-Dispersive Channels

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