GLONASS频间码偏差特性分析及其在宽巷模糊度固定中的应用

摘要

GLONASS inter-frequency code biases(IFCBs)vary with receiver manufacturers,firmware versions,and antenna types.IFCBs are hardly corrected or modeled precisely,so that Hatch-Melbourne-Wübbena(HMW)combination observation contains a systemic bias and cannot applied into GLONASS wide-lane ambiguity resolution.Utilizing the residuals of GLONASS HMW combination observations,we propose an algorithm to estimate IFCB of different sites(DS-IFCB).The experiment results show that DS-IFCB is long term stability and the sizes of DS-IFCBs in some homogeneous baselines(composed by same type of devices,i.e.receiver type,version and antenna)are larger than 0.5 meters.In order to achieve wide-lane ambiguities in real-time,DS-IFCBs,estimated with previous observations,are used as priors to cancel IFCBs in current observations.After DS-IFCB offset,both the success rate and correct rate of GLONASS wide-lane ambiguity resolutions are improved,regardless of whether baselines are equipped with homogeneous devices.The correct rates of all baselines are higher than 98%.%受接收机类型、固件版本和天线的影响,GLONASS IFCB变化规律复杂且难以有效改正,导致GLONASS HMW组合包含系统性偏差,无法用于 GLONASS宽巷模糊度固定.本文提出一种基于GLONASS HMW组合观测值残差的站间IFCB估计方法,并对站间IFCB变化特性进行分析.结果表明,站间IFCB长期稳定,少数相同类型硬件(包括接收机类型、固件版本和天线)站间IFCB可达0.5 m.为削弱伪距多路径效应对站间IFCB估值的影响,基于一个轨道重复周期的观测数据求得一组站间IFCB对实时观测值进行补偿,实现HMW组合平滑序列直接用于GLONASS宽巷模糊度实时固定.进行站间IFCB补偿后,基线宽巷模糊度固定正确率均在98% 以上.