Orthogonal Time Frequency Space Modulation

By Ronny Hadani, S. Rakib, Shachar Kons, Michael Tsatsanis, Anton M. Monk, C. Ibars, J. Delfeld, Yoav Hebron, Andrea J. Goldsmith, Andreas F. Molisch and 1 more. IEEE Wireless Communications and Networking Conference, 2017

1,809 citations recorded by the source corpus.

A new two-dimensional modulation technique called Orthogonal Time Frequency Space (OTFS) modulation designed in the delay-Doppler domain is introduced. Through this design, which exploits full diversity over time and frequency, OTFS coupled with equalization converts the fading, time-varying wireless channel experienced by modulated signals such as OFDM into a time-independent channel with a complex channel gain that is roughly constant for all symbols. Thus, transmitter adaptation is not needed. This extraction of the full channel diversity allows OTFS to greatly simplify system operation and significantly improves performance, particular in systems with high Doppler, short packets, and large antenna arrays. Simulation results indicate at least several dB of block error rate performance improvement for OTFS over OFDM in all of these settings. In addition these results show that even at very high Dopplers (500 km#x002F;h), OTFS approaches channel capacity through linear scaling of throughput with the MIMO order, whereas the performance of OFDM under typical design parameters breaks down completely.

Subfields: Electrical and Electronic Engineering

View Paper: https://www.semanticscholar.org/paper/cbf314e936bc79792193f2fa8acda356d2355ebd

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In Electrical and Electronic Engineering

Citations in the corpus

A Primer on Rate-Splitting Multiple Access: Tutorial, Myths, and Frequently Asked Questions (2022, background): “OTFS was recently proposed as a new two-dimensional modulation scheme [221] [222], which multiplexes information symbols in the delay-Doppler (DD) plane (or domain) rather than the time-frequency (TF) domain as for conventional multi-carrier modulation or orthogonal frequencydivision multiplexing (O”
Embedded Pilot-Aided Channel Estimation for OTFS in Delay–Doppler Channels (2018, methodology): “In general, OTFS uses the delay-Doppler channel response [1]–[3] to parameterize the effects of a time-varying channel on any transmitted waveform.”
An Overview of Signal Processing Techniques for Terahertz Communications (2020, background): “OTFS [258] is promising for THz mobility scenarios with Doppler shifts that severely affect the automatic frequency control range.”
Low Complexity Iterative Rake Decision Feedback Equalizer for Zero-Padded OTFS Systems (2020, methodology): “, QAM) over both time and frequency to achieve maximum effective1 diversity [1], [2].”
Waveform Design and Performance Analysis for Full-Duplex Integrated Sensing and Communication (2021, methodology): “Another emerging modulation technique termed orthogonal time frequency space (OTFS) modulation [34] has also been studied for ISAC [33], which is more robust to large Doppler frequency shifts than OFDM.”
Overview of Millimeter Wave Communications for Fifth-Generation (5G) Wireless Networks—With a Focus on Propagation Models (2017, background): “Orthogonal time-frequency-space modulation that spreads the signals in the time-frequency plane has also been suggested, due to superior diversity and higher ﬂexibility in pilot design [58].”
Integrated Sensing and Communications: Toward Dual-Functional Wireless Networks for 6G and Beyond (2021, background): “, low-earth-orbit (LEO) satellite networks [223], [224], Terahertz (THz) communications and sensing [225], [226], digital twins [227], [228], orthogonal time frequency space (OTFS) modulation [229]–[231], and more.”
Off-grid Channel Estimation with Sparse Bayesian Learning for OTFS Systems (2021, background): “Recently, a new modulation waveform, namely orthogonal time-frequency space (OTFS), has been proposed as a promising candidate for realizing high-mobility communications owing to its intrinsic advantages of handling the problems caused by Doppler effect [3], [4].”
MIMO-OTFS in High-Doppler Fading Channels: Signal Detection and Channel Estimation (2018, background): “, 500 km/h vehicle speeds) is especially notable, as OFDM performance breaks down in such high-Doppler scenarios [9].”
Practical Pulse-Shaping Waveforms for Reduced-Cyclic-Prefix OTFS (2019, background): “Remark 1: From [1], [2], [16], the input–output relation for the ideal waveforms case can be written as a 2D convolution in the form Therefore, the effective channel matrix in Theorem 1 can be obtained from (30) by replacing h i with h i α i ( m, n ) ([17]), where the correction factor is given by…”
Integrated Sensing and Communication Signals Toward 5G-A and 6G: A Survey (2023, methodology): “Meanwhile, since OTFS signal has no ICI, it achieves more accurate Doppler frequency shift estimation, achieving more accurate velocity estimation compared with OFDM signal [19].”
A Tutorial on Near-Field XL-MIMO Communications Toward 6G (2023, neutral): “…been proposed to resolve these issues, such as windowing, ﬁlter bank multi-carrier (FBMC) [220], single-carrier discrete Fourier transform-spread OFDM (DFT-s-OFDM), and orthogonal time frequency space (OTFS) [224], they either incur performance loss or exacerbate the signal processing complexity.”
Integrated Sensing and Communication-Assisted Orthogonal Time Frequency Space Transmission for Vehicular Networks (2021, methodology): “The DD domain symbols are then spread over the time-frequency (TF) domain using the inverse symplectic ﬁnite Fourier transform (ISFFT), given by [19] X where n and m denotes the time and frequency indices, respectively.”
5G Key Technologies for Smart Railways (2020, background): “The orthogonal time-frequency space modulation, which performs modulation in the delay Doppler domain, has been proposed in [81] to address this issue.”
Channel Estimation for Orthogonal Time Frequency Space (OTFS) Massive MIMO (2019, methodology): “As a result, OTFS has improved performance over the traditional OFDM especially in high-mobility scenarios [8]–[10].”
Interference Cancellation and Iterative Detection for Orthogonal Time Frequency Space Modulation (2018, methodology): “Time–Frequency Domain Analysis For ideal waveforms, the following result was given in [5] without proof.”
6G for Vehicle-to-Everything (V2X) Communications: Enabling Technologies, Challenges, and Opportunities (2020, background): “Recently, orthogonal time-frequency-space (OTFS) has emerged as an effective multi-carrier scheme by spreading each information symbol over a two dimensional (2D) orthogonal basis function spanning across the time-frequency domain [91]–[93].”