面向卫星互联网的时频同步技术研究

his paper focuses on the urgent needs of high-speed, efficient, and reliable communications in the LEO satellite Internet environment, and aims at the problem that the performance of traditional time-frequency synchronization technology in the LEO satellite channel has seriously deteriorated, proposes a design scheme of preamble sequence based on linear frequency modulation signal and a time-frequency fusion synchronization algorithm based on fractional Fourier transform. After simulation verification, the proposed algorithm has stronger adaptability to low orbit satellite channels compared to traditional time-frequency synchronization methods, and has significant improvements in the accuracy, reliability, and computational complexity of time-frequency offset estimation.