一种纬度估计算法优化及误差抑制技术研究

Research on Latitude Estimation Algorithm and Error Suppression Technology of Compass System

在战时,舰船会由于卫星信号受干扰等情况影响而无法获取准确的当地地理位置信息。这就需要船舶能够在行进中估计纬度。为提高纬度估计精度,提出了一种舰船行进中纬度估计算法优化及误差抑制方法。首先利用重力加速度在惯性坐标系的投影,构建几何解析方程求解一定精度的纬度信息。通过选取重力加速度最优积分区间,提高了动基座条件下的纬度估计精度。行进中的舰船易受风浪等因素影响,导致罗经测量的地球自转角速度和重力加速度受到严重干扰,因此纬度估计精度下降。针对该问题,采用最小二乘拟合算法对外部扰动误差进行抑制。仿真结果表明,该方法能够有效提高舰船行进中的纬度估计精度。

As it is difficult for ships to obtain accurate local geographic information during wartime due to satellite interference and other conditions, it is necessary for the ship to be able to estimate latitude during the voyage. In order to improve the accuracy of latitude estimation, a ship latitude estimation error suppression method is proposed. First, the projection of gravity acceleration in the inertial coordinate system is used to construct geometric analytical equation to solve latitude information with certain precision. By selecting the best integral interval of gravity acceleration, the latitude estimation accuracy under the condition of moving base is improved. Affecting factors such as wind and waves during the sailing of a ship, seriously interferes the measurement of the earth’s rotation angular velocity and gravitational acceleration measured by the compass, resulting in the decrease of latitude estimation accuracy. To solve this problem, the least square fitting method is used to suppress the external disturbance error. The simulation results show that this method can effectively improve the accuracy of ship latitude estimation during the voyage.