OTFS技术研究现状与展望

doi:10.11959/j.issn.1000-0801.2021221

摘要/Abstract

摘要：

正交时频空（orthogonal time frequency space，OTFS）技术是近年来出现的一种新型多载波调制技术。在 OTFS 技术中，数据信号在时延—多普勒域产生，经过逆偶有限傅里叶变换实现信号的时频二维扩展，以解决正交频分复用（orthogonal frequency division multiplexing，OFDM）技术在时频双选信道下干扰严重的问题。介绍了OTFS技术的基本原理，通过仿真验证其相比于OFDM技术的优势。对其研究现状进行分析总结，指出 OTFS 技术中的多址接入、信道估计和线性接收机等研究方向目前有待解决的问题。对 OTFS 技术在雷达—通信一体化系统中的应用前景进行分析和展望。

关键词: 多载波, 多普勒频移, 正交频分复用

Abstract:

Recently, a new multi-carrier modulation technique termed orthogonal time frequency space (OTFS) was proposed.In the OTFS modulation, the data symbols are modulated at the delay-Doppler plane and spread on all the time-frequency resource elements with the inverse symplectic finite Fourier transform.Compared with the conventional orthogonal frequency division multiplexing (OFDM) technique, the OTFS modulation performs better in the time-varying and frequency-selective channel.The state of art of OTFS was reviewed and summarized.Simulation results were presented to demonstrate the performance advantage of OTFS over the conventional OFDM.The remainder problems of multi-accessing, channel estimation and linear equalization in OTFS was given.The application of OTFS signal in joint Radar and communication system was also analyzed.

Key words: multi-carrier, Doppler frequency shift, orthogonal frequency division multiplexing

中图分类号:

TP393

龙航, 王森, 徐林飞, 贾寅华, 代璐. OTFS技术研究现状与展望[J]. 电信科学, 2021, 37(9): 57-63.

Hang LONG, Sen WANG, Linfei XU, Yinhua JIA, Lu DAI. OTFS technology research and prospect[J]. Telecommunications Science, 2021, 37(9): 57-63.

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载频	4 GHz
M	120
N	12
子载波间隔	OFDM15：15 kHz
	OFDM30：30 kHz
	OTFS：15 kHz
信道模型	两径信道，[0,﹣1.5]dB，[0,2.51]μs
编码调制	QPSK，LDPC，码率0.188 5