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arXiv · 2010.03344

Orthogonal Time-Frequency Space Modulation: A Promising Next-Generation Waveform

Zhiqiang Wei·Weijie Yuan·Shuangyang Li·Jinhong Yuan·Ganesh Bharatula·Ronny Hadani·Lajos Hanzo
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Abstract

The sixth-generation (6G) wireless networks are envisioned to provide a global coverage for the intelligent digital society of the near future, ranging from traditional terrestrial to non-terrestrial networks, where reliable communications in high-mobility scenarios at high carrier frequencies would play a vital role. In such scenarios, the conventional orthogonal frequency division multiplexing (OFDM) modulation, that has been widely used in both the fourth-generation (4G) and the emerging fifth-generation (5G) cellular systems as well as in WiFi networks, is vulnerable to severe Doppler spread. In this context, this article aims to introduce a recently proposed two-dimensional modulation scheme referred to as orthogonal time-frequency space (OTFS) modulation, which conveniently accommodates the channel dynamics via modulating information in the delay-Doppler domain. This article provides an easy-reading overview of OTFS, highlighting its underlying motivation and specific features. The critical challenges of OTFS and our preliminary results are presented. We also discuss a range of promising research opportunities and potential applications of OTFS in 6G wireless networks.

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Zhiqiang Wei, Weijie Yuan, Shuangyang Li, Jinhong Yuan, Ganesh Bharatula, Ronny Hadani, Lajos Hanzo. 2020-10-07. Orthogonal Time-Frequency Space Modulation: A Promising Next-Generation Waveform. https://arxiv.org/abs/2010.03344

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