中国空间科学技术

中国空间科学技术 ›› 2026, Vol. 46 ›› Issue (1): 24-35.doi: 10.16708/j.cnki.1000-758X.2026.0002

• 面向星地融合的卫星互联网专题 • 上一篇    

星地场景下基于RM编码的OTFS系统峰均比抑制方法

宋强健,张馨月,朱立东*   

  1. 电子科技大学通信抗干扰全国重点实验室,成都 611731
  • 收稿日期:2024-10-29 修回日期:2025-01-26 录用日期:2025-02-07 发布日期:2025-11-28 出版日期:2026-01-30

Peak-to-average power ratio suppression method for OTFS system based on RM coding in satellite-to-ground scenarios

SONG Qiangjian,ZHANG Xinyue,ZHU Lidong*   

  1. National Key Laboratory of Wireless Communications, University of Electronic Science and Technology of China, Chengdu 611731,China
  • Received:2024-10-29 Revision received:2025-01-26 Accepted:2025-02-07 Online:2025-11-28 Published:2026-01-30

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摘要： 正交时频空(Orthogonal Time Frequency Space, OTFS)调制因其在高多普勒频偏环境下的可靠传输能力,已成为低轨卫星等高动态通信场景的关键技术。然而,作为多数波调制技术,OTFS信号的高峰均功率比(Peak-to-Average Power Ratio, PAPR)易导致功放进入非线性工作状态,产生信号失真,影响通信可靠性和稳定性。格雷互补序列因其特殊的定义,使得该序列的最大峰均比不超过3 dB。基于里德-穆勒(Reed-Muller, RM)编码与格雷互补序列之间的特殊联系,提出了一种基于RM编码的OTFS系统的峰均功率比抑制方法。在发射端,首先利用RM编码将原始比特流序列编码转换为格雷互补序列形式,再进行星座映射与OTFS调制,得到低峰均功率比的发射信号。在接收端,为了实现对这种特殊编码信号的准确译码,设计了一种两步级联译码算法,通过降噪选择译码与单项双系数译码的级联实现了对具有格雷互补序列的RM编码的纠错译码,保证了通信传输的可靠性。仿真结果表明,在低轨卫星通信场景下,该编码方法可以将OTFS系统发射信号的峰均功率比抑制在3 dB以内;相较于OFDM系统,OTFS系统具有更强的鲁棒性;两步级联译码算法实现了较高信噪比(>6 dB)下更高的传输可靠性。上述方案的提出不仅为OTFS调制技术在星地高动态通信场景中的应用提供了有力的技术支持,也为未来多数波调制信号的峰均比抑制提供了新的参考。

关键词: 峰均功率比, 星地通信, 里德-穆勒编码, 格雷互补序列, 正交时频空, 级联译码

Abstract: Orthogonal time frequency space (OTFS) modulation, known for its reliable transmission capability in high Doppler shift environments, has become a key technology for high-mobility communication scenarios such as low earth orbit (LEO) satellite systems. However, as a multicarrier modulation technique, OTFS signals are characterized by a high peak-to-average power ratio (PAPR), which can cause power amplifiers to operate in a nonlinear region, resulting in signal distortion and negatively impacting communication reliability and stability. The Golay complementary sequence, due to its unique properties, ensures that the maximum PAPR of the sequence does not exceed 3 dB. Based on the special relationship between Reed-Muller (RM) coding and Golay complementary sequences, a PAPR reduction method for OTFS systems using RM coding is proposed. At the transmitter, RM coding is used to encode the original bitstream into Golay complementary sequence forms, followed by constellation mapping and OTFS modulation to generate a low-PAPR transmitted signal. At the receiver, to accurately decode this specially encoded signal, a two-step concatenated decoding algorithm is designed. This algorithm combines coset selection decoding and monomial coefficient decoding to achieve error correction for RM codes with Golay complementary sequences, ensuring communication reliability. Simulation results show that, in low earth orbit satellite communication scenarios, the proposed coding method suppresses the peak-to-average power ratio of OTFS system transmitted signals to within 3 dB. Compared with the OFDM system, the OTFS system demonstrates greater robustness. The two-step concatenated decoding algorithm achieves higher transmission reliability at high signal-to-noise ratios (>> 6 dB). This proposed scheme not only provides strong technical support for the application of OTFS modulation in high-mobility satellite-to-ground communication scenarios, but also offers a new reference for PAPR reduction in future multicarrier modulation signals.

Key words: peak-to-average power ratio, satellite to ground communication, Reed-Muller coding, Golay complementary sequences, orthogonal time frequency space, cascaded decoding