An improved GNSS ambiguity best integer equivariant estimation method with Laplacian distribution for urban low-cost RTK positioning  

作　　者：Ying Liu Wanke Liu Xiaohong Zhang Yantao Liang Xianlu Tao Liye Ma 

机构地区：[1]School of Geodesy and Geomatics,Hubei Luojia Laboratory,Wuhan University,129 Luoyu Road,Wuhan,430079,Hubei,China [2]Chinese Antarctic Center of Surveying and Mapping,Wuhan University,129 Luoyu Road,Wuhan,430079,Hubei,China [3]School of Instrument Science and Engineering,Southeast University,Nanjing,Jiangsu,China [4]The 54,Research Institute of China Electronics Technology Group Corporation,Shijiazhuang,050081,Hebei,China [5]State Key Laboratory of Satellite Navigation System and Equipment Technology,Shijiazhuang,050081,Hebei,China

出　　处：《Satellite Navigation》2024年第1期109-124,共16页卫星导航（英文）

基　　金：funded by the National Key R&D Program of China(Grant No.2021YFC3000502);the National Natural Science Foundation of China(Grant No.42274034);the Major Program(JD)of Hubei Province(Grant No.2023BAA026);the Special Fund of Hubei Luojia Laboratory(Grant No.2201000038);the Research project of Chongqing Administration for Marktet Regulation,China(Grant No.CQSJKJ2022037).

摘　　要：The integer least squares(ILS)estimation is commonly used for carrier phase ambiguity resolution(AR).More recently,the best integer equivariant(BIE)estimation has also attracted an attention for complex application scenarios,which exhibits higher reliability by a weighted fusion of integer candidates.However,traditional BIE estimation with Gaussian distribution(GBIE)faces challenges in fully utilizing the advantages of BIE for urban low-cost positioning,mainly due to the presence of outliers and unmodeled errors.To this end,an improved BIE estimation method with Laplacian distribution(LBIE)is proposed,and several key issues are discussed,including the weight function of LBIE,determination of the candidates included based on the OIA test,and derivation of the variance of LBIE solutions for reliability evaluation.The results show that the proposed LBIE method has the positioning accuracy similar to the BIE using multivariate t-distribution(TBIE),and significantly outperforms the ILS-PAR and GBIE methods.In an urban expressway test with a Huawei Mate40 smartphone,the LBIE method has positioning errors of less than 0.5 m in three directions and obtains over 50%improvements compared to the ILS-PAR and GBIE methods.In an urban canyon test with a low-cost receiver STA8100 produced by STMicroelectronics,the positioning accuracy of LBIE in three directions is 0.112 m,0.107 m,and 0.252 m,respectively,with improvements of 17.6%,27.2%,and 26.1%compared to GBIE,and 23.3%,28.2%,and 30.6%compared to ILS-PAR.Moreover,its computational time increases by 30–40%compared to ILS-PAR and is approximately half of that using TBIE.

关 键 词：Ambiguity resolution Best integer equivariant estimation Laplacian distribution Urban environments Low-cost GNSS receivers Real-time kinematic 

分 类 号：P22[天文地球—大地测量学与测量工程]