一种序贯平差中长基线模糊度的解算方法

虚拟参考站(VRS)技术是目前GPS网络RTK系统研究领域的热点之一,而参考站间整周模糊度的在线解算则是VRS/RTK的关键技术。本文针对中长基线的整周模糊度解算,采用两步法求解:一是提出了采用消电离层伪距组合和双频相位组合法求解宽巷模糊度,该方法既不需要高精度的P码,也不需要顾及电离层的影响;二是对于解算L1双差模糊度,探讨了采用序贯最小二乘法解算模糊度,提出一种改进的序贯最小二乘方法,本方法既能削弱模糊度解算过程中法方程的病态性,又不影响模糊度固定时间,并结合算例进行了分析。

An approach for ambiguity resolution based on improved sequential adjustment suitable for medium-long baseline

The concept for Real-time Kinematic GPS positioning with virtual reference station has been developed greatly during the past few years.The online ambiguity resolution in references station network is a key technology of VRS/RTK.In this paper,in order to deal with this problem,a two-step method was chosen.Step one:as the two common methods to solve wide-lane ambiguity certainly has their limitations,this paper presented ionosphere-free dual-phase pseudo-range combination for solving wide-lane ambiguity.This method doesn’t need high-precision Pcode and doesn’t need to take into account the impact of the ionosphere.Step two:for solving L1 double difference ambiguity,this paper discussed the sequential least squares for ambiguity resolution,and presented an improved sequential least squares method which could eliminate the ill-conditioned of the formal equation during solving L1 ambiguity,while not affect the time of ambiguity resolution.