Research on joint timing and frequency synchronization algorithms of LEO satellite communication system

doi:10.7523/j.ucas.2024.053

Abstract

Abstract: The integration of low orbit satellite (LEO) with 5G in the mobile communication system presents extensive application prospects. To ensure effective establishment of communication links between users and base stations, as well as reliable data transmission, time-frequency synchronization technology plays a crucial role. However, traditional timing and frequency synchronization algorithms face limitations when dealing with millimeter wave frequency bands, large bandwidths, high Doppler frequency shifts and change rates, and low signal-to-noise ratios in low orbit satellite channels. These limitations result in decreased estimation accuracy. For the uplink service data channel of a 5G-based low orbit satellite communication system, a joint timing and frequency synchronization algorithm based on weighted built-in synchronization sequences is proposed to improve the accuracy of timing and frequency offset estimation. Simulation results demonstrate that the proposed timing and frequency synchronization algorithm outperforms traditional algorithms with comparable complexity in terms of synchronization performance.

Key words: LEO satellite communication, OFDM, timing synchronization, frequency synchronization

CLC Number:

TN927+.23

LI Yanping, SHANG Lin, LI Guotong. Research on joint timing and frequency synchronization algorithms of LEO satellite communication system[J]. Journal of University of Chinese Academy of Sciences, DOI: 10.7523/j.ucas.2024.053.

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