GNSS模糊度搜索空间的相关性分析与优化策略  

Correlation Analysis and Optimization Strategy of GNSS Ambiguity Search Space

作　　者：李新忠[1] 熊永良[1] 徐韶光[1] LI Xinzhong;XIONG Yongliang;XU Shaoguang(Faculty of Geosciences and Engineering,Southwest Jiaotong University,Chengdu 611756,China)

机构地区：[1]西南交通大学地球科学与工程学院,成都市611756

出　　处：《大地测量与地球动力学》2024年第7期667-673,共7页Journal of Geodesy and Geodynamics

基　　金：国家自然科学基金(41674028,41274044);四川省科技计划(2022YFG0169)。

摘　　要：初始搜索空间设置是否合理,会直接影响模糊度解算的可靠性和搜索效率。针对BDS系统星座特性,有必要对BDS2和BDS3在不同卫星数、不同频率下椭球容积与候选点个数的相关性以及数据冗余的影响进行分析。对于目标函数方法在确定模糊度搜索空间时容易产生过多的模糊度候选向量这一缺点,提出一种优化的搜索空间确定方法,并通过实验验证改进方法的有效性。结果表明,改进的搜索空间确定方法可明显减少实际模糊度候选向量个数,平均改进率最大可达35.02%,且保证94%的空间内所包含的候选向量个数符合要求。改进的搜索空间确定方法应用于不同搜索方法后搜索效率平均提升近33%,有利于分离出初始搜索空间中的冗余候选向量,从而提高模糊度搜索效率。Whether the initial search space is set reasonably or not directly affects the reliability and search efficiency of ambiguity resolution.In view of the constellation characteristics of BDS system,it is necessary to analyze the correlation between ellipsoid volume and the number of candidate points,and the effect of data redundancy for BDS2 and BDS3 under different satellite numbers and frequencies.For the drawback that objective function method is prone to produce too many candidate vectors when determining the ambiguity search space,we propose an optimized search space determination method,and verify the effectiveness of improved method through experiments.The results show that the improved search space determination method significantly reduces the number of actual ambiguity candidate vectors,with average improvement up to 35.02%,and ensures that the number of candidate vectors contained in 94%space satisfies the requirements.The improved search space method improves search efficiency by nearly 33%on average after applying it to different search methods,which is conducive to separating the redundant candidate vectors in initial search space,thus improving the ambiguity search efficiency.

关 键 词：GNSS 整数最小二乘 搜索空间 椭球容积 目标函数 

分 类 号：P228[天文地球—大地测量学与测量工程]