一种基于局部球面约束的GPS单频瞬时定向方法

The New Method for GPS Single Frequency Instantaneous Heading Determination Based on Local Sphere Constraint

GPS单频瞬时定向具有高精度、低成本和无需周跳检测等诸多优势,但成功率依赖于高精度的伪码测距辅助,同时对可见星数目也较敏感,不利于载体在城市峡谷等遮挡环境中的应用。针对此问题,提出一种带有局部球面约束的整数最小二乘估计方法,算法不依赖于高精度的伪码测距辅助,并充分将姿态角概略信息融入到短基线观测模型中,增强了模型强度,提高了定向解的可靠性。实际试验表明,本方法可以显著提高整数最小二乘的成功率,适用于卫星可见性受限环境下的定向解算。

GPS single-frequency instantaneous heading determination has many advantages,such as high accuracy,low cost and no cycle slip detection. However,the success rate depends on high-precision pseudocode ranging assistance and is sensitive to the number of visible satellites,which is not conducive to the applications in blocking environment such as urban canyons. In order to solve this problem,an integer least squares estimation method with local spherical constraints is proposed in this paper. The algorithm does not depend on the high-precision pseudo-code ranging assistance and fully incorporates the coarse information of attitude angle into the short baseline observation model,which enhances the strength of the model and improves the reliability of the heading solution. Actual experimental results show that this method can significantly improve the success rate of integer least squares and it is suitable for heading determination under poor satellite visibility.