FirCAR算法的OTF快速定位方法  

An OTF Fast Positioning Method Based on FirCAR Algorithm

作　　者：冯威[1] 黄丁发[1] 张熙[1] 

机构地区：[1]西南交通大学地球科学与环境工程学院,四川成都610031

出　　处：《测绘学报》2012年第4期529-535,共7页Acta Geodaetica et Cartographica Sinica

基　　金：国家自然科学基金(41104020;40771173);国家863计划(2007AA12Z315)

摘　　要：根据GNSS不同频率间整周模糊度的约束关系,提出一种基于多频整周模糊度间关系约束的模糊度新算法(dual-frequency integer relationship constrained ambiguity resolution,FirCAR)。FirCAR可快速动态解算出高高度角卫星的整周模糊度,将已经固定的整周模糊度视为高精度的伪距观测值应用到下一步的浮点解重算中。结合模糊度搜索算法,如LAMBDA,在模糊度搜索方面的高效性,根据重算后的浮点解进一步解算其他未固定的模糊度解。模糊度固定成功后,即可实现OTF(on the fly)快速定位。实测数据表明,FirCAR算法在静态和动态观测条件下,模糊度初始化所用的平均观测历元数分别为1.04和1.10。与常规的模糊度搜索算法的对比试验表明,结合FirCAR算法模糊度固定所用的观测历元数分别减少了39%和18%。On the basis of the relationship of integer ambiguities among different GNSS frequencies, a new ambiguity resolution algorithm is proposed, named FirCAR （dual-frequency integer relationship constrained ambiguity resolution）, which givesa fast search time in determining the integer ambiguities of high-elevation satellites. As a subset of ambiguities fixed by FirCAR, these ambiguity-fixed observations act as precise ranges in the next ambiguity resolution procedure, to improve the precision of the new float ambiguities. The remaining unfixed ambiguities will be resolved by ambiguity search algorithm such as LAMBDA which provides an efficient ambiguity search progress with the new float solution. And finally the OTF fast positioning is accomplished as the ambiguities fixed. Experimental results from two short baselines show that, for the static and kinematics scenarios, the average number of epochs required to fix ambiguities with the proposed method is 1. 04 and 1. 10 respectively. Comparing with the conventional ambiguity search algorithm, combining FirCAR reduces the required epoch number by about 39% and 18% in the situation of static and kinematics respectively.

关 键 词：GNSS 整周模糊度 FI rCAR 搜索算法 OTF 

分 类 号：P237[天文地球—摄影测量与遥感]