一种改进的GPS/GLONASS组合精密单点定位算法研究

Study on Modified Algorithm of Combined GPS/GLONASS Precise Point Positioning

讨论了GPS精密单点定位的数学模型。提出了一种改进的GPS精密单点定位算法,该算法是把电离层延迟分为一阶电离层延迟和二阶电离层延迟的方法。分别对各阶电离层进行研究:一阶电离层采用线性组合的方式消除,二阶电离层延迟采用模型估计方法进行消除,最终达到消除电离层影响的目的。最后把该算法应用于GPS/GLONASS组合精密单点定位中,分别从E、N、U 3个定位方向上比较了GPS和GPS/GLONASS组合精密单点定位的定位结果,计算结果表明,该算法在一定程度上提高了定位的精度。较单系统GPS精密单点定位,它能够加快定位的收敛速度,保证定位的连续性。

Discussing the mathematical model of GPS precise single point positioning, a modified algorithmof GPS precise point positioning algorithm is proposed.The algorithm is to divide the ionospheric delay into first-order ionospheric delay and second order ionospheric delay. The first-order ionospheric delay is eliminated by the linear combination, while the second order ionospheric delay is eliminated by the method of model estimateion, achieving the elimination of the impact of the ionosphere finally. At last, the algorithm is applied to GPS/GLONASS combined precise point positioning, and the positioning results of combined precision single point positioning of GPS and GPS/GLONASS were compared in three directions of E, N and U, respectively. The calculation results show that, the algorithm can improve the precision of positioning to a certain extent. Compared with single system of GPS precise point positioning, it could accelerate the positioning of convergence speed, and guarantee the continuity of positioning.