基于加权的伪距和历元间相位差分模型GPS单点定位方法

在星载GPS精密定轨或单点定位中,尤其单频接收机的情况下,仅利用相位观测值,由于需要解算模糊度方程通常奇异,仅利用伪距观测资料,由于伪距观测值的噪声影响使得难以实现高精度定位要求。鉴于此,本文讨论了基于加权的伪距和历元间相位差分模型的GPS单点定位方法,该方法既能改善方程奇异性,又无需考虑模糊度因素,能确保观测值的精度。本文分别探讨了伪距观测方程和历元间差分相位观测方程,并给出了联合误差模型,推导了权值的计算公式和参数解算公式,最后基于动态单点定位考虑,探讨了基于加权的伪距和历元间相位差分模型的序贯最小二乘参数解算一般表达式。

GPS point positioning based on weighted between pseudo-range and time-differenced carrier-phase model

In on-board GPS precise orbit determination(POD) or precise point positioning(PPP),especially with single-frequency receiver,the equation will be singularity only with carrier phase measurements,and it is difficult to implement high-precision positioning only with pseudo-range measurements because of thermal noise.Aiming at these situations,a combined method weighted between pseudo-range and time-differenced carrier-phase is put forward in this paper,it can not only improve the singularity of equation but also avoid ambiguity solution and ensure the positioning precision.Pseudo-range measurement equation,time-differenced carrier-phase measurement,and their combined equation are discussed in this paper.The authors also deduce the computing weight formula and parameters solution formula.Based on dynamic point positioning,the Sequential Least Squares parameters solution formula with weighted between pseudo-range and time-differenced carrier-phase is discussed in this paper.