多年来一直在使用的船舶自动识别系统(AIS)作为一种海上监视和导航的通信系统, 其服务范围被限制在40海里。近年来, 一种新的基于卫星的AIS被提出, 该系统能提供全球覆盖服务,然而其存在由相对卫星/船舶运动引起的频率偏移问题。为了更好地解决这一问题, 文章提出了一种新的基于多普勒频移估计算法的星载多普勒频移估计算法, 利用二阶矩阵及四阶矩阵等代数运算, 从信号中提取多普勒频移, 并给出了估计表达式。最后, 通过数值仿真验证了该算法的有效性, 仿真结果还验证了该算法的优越性。

The Automatic Identification System (AIS), which has been used for many years, is a communication system for maritime surveillance and navigation, and its service scope is limited to 40 nautical miles. In recent years, a new satellite based AIS has been proposed, which can provide global coverage services. However, it encounters frequency offset caused by relative satellite / ship motion. In order to solve this problem, this paper proposes a new Doppler shift estimation algorithm. The second-order matrix and the fourth-order matrix are used to extract the doppler shift from the signal, and the estimation expression is then provided. Finally, the validity of the method is verified by numerical simulation, and the superiority of the method is verified by simulation results.