Abstract
The estimation of channels in shallow sea mobile communication systems presents significant challenges due to multipath propagation and non-uniform Doppler effects. Traditional channel estimation methods, such as least squares and least mean squares, fail to accurately handle these issues, leading to errors. To address these limitations, this study proposes a high-precision channel estimation method based on iterative cancellation. The method uses cross-correlation of complex signals to identify Doppler shifts, select the most prominent shifts, and subtract corresponding reference signal components. This iterative process allows for precise separation of multipath signals and accurate estimation of the channel impulse response. Simulation and sea trial results show that the proposed method provides high temporal and amplitude resolution, robust noise immunity, and effective compensation for non-uniform Doppler effects, even under high-speed mobility. The method significantly improves channel estimation accuracy compared to traditional techniques, particularly in dynamic shallow sea environments. These findings contribute to enhancing the reliability and efficiency of underwater communication systems, which is critical for both military and civilian applications such as underwater navigation and environmental monitoring.