A Doppler frequency offset estimation and compensation method in low earth orbit satellite systems

To address the challenges of Doppler frequency offset (DFO) estimation in low earth orbit (LEO) satellite communication scenarios, a method for DFO estimation and compensation is proposed in LEO satellite systems. The method initially employs ephemeris data and terminal information for a coarse estimation of the DFO, followed by a pre-compensation of the coarse estimation results. After pre-compensation, a pilot segment method is utilized for residual frequency offset estimation. Finally, the coarse frequency offset estimation derived from ephemeris data is treated as prior information, which is integrated with the pilot segment-based frequency offset estimation method to achieve precise frequency offset estimation using the maximum a posteriori probability approach. Simulation results show the superiority of the proposed scheme in LEO satellite systems.