An Ambiguity Algorithm for Single Frequency and Single Epoch Combination of GPS and BDS
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摘要: 针对单频单历元组合载波相位差分技术(RTK)定位过程中存在的秩亏及模糊度解算病态等问题,提出了一种模糊度降相关的新方法。该方法引入伪距观测值进行辅助解算。首先采用经验分权法对伪距与载波相位观测值分配权重,并通过加权最小二乘法获得整周模糊度浮点解及协方差。然后通过对整周模糊度浮点解的方差-协方差矩阵进行降序排列和剔除病态模糊度。最后利用修正后的浮点解迭代搜索模糊度的整数解。试验结果表明而且可以起到良好的模糊度降相关的效果定位。Abstract: Aiming at the problem of rank-defect and ill-conditioned ambiguity resolution in the process of single frequency single epoch combined RTK positioning, a new method for ambiguity decorrelation is proposed, in which pseudorange observations is introduced as auxiliary solution.First, we adopt the empirical decentralization method to assign weights to the pseudorange and carrier phase observations, and obtain the floating resolution of ambiguities by weighted least squares. Then the ill-conditioned ambiguity resolution can be eliminated by the descending order of variance-covariance matrix of the floating resolution of ambiguitiesand Cholesky triangular decomposition. Finally, we use the modified floating solution toiterate the search of the integer solution of ambiguity. The experimental results show that the down-correlation algorithm can not only improve the positioning accuracy, but also can reduce the correlativity of the ambiguity, which is suitable for RTK positioning.
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Key words:
- Single frequency /
- single epoch /
- descending order /
- ambiguity resolution
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[1] HOFMANN-WELLENHOF B, LICHTENEGGER H, COLLINS J. Global Positioning System: Theory and practice[M].5th ed. NEW York: Springer Wien,2001.
[2] XU G C.GPS Theory: Algorithms and applications[M].2nd ed. Berlin:Springer-Verlag,2007. [3] FREI E, BEUTLER G. Rapid static positioning based on the Fast Ambiguity Resolution Approach”FARA”: Theory and first results [J].Manuscripta Geodaetica,1990,15(4): 325-356. [4] HATCH R. Instantaneous ambiguity resolution[JP][C]//IAG Symposia Proceedings of Kinematic Systems in Geodesy, Surveying, and Remote Sensing:107.New York: Springer, 1990: 299-308. [5] TEUNISSEN P J G. A new method for fast carrier phase ambiguity estimation[C]//Proceedings IEEE Position, Location and Navigation Symposium PLANS’94, Las Vegas: IEEE, 1994:562-573. [6] TEUNISSEN P J G. The Invertible GPS Ambiguity Transformation[J].Manuscripta Geodaetica, 1995,20(6): 489-497. [7] TEUNISSEN P J G. The Least-squence ambiguity decorrelation adjustment: A method for fast GPS integer ambiguity estimation[J].Journal of Geodesy,1995,70(1/2):65-82. [8] KIM D,LANGLEY R B. An optimized least-squares technique for improving ambiguity resolution and computational efficiency[C]//Proceedings of ION GPS-99:12th International Technical Meeting of the Satellite Division of The Institute of Navigation. Nashville: ION, 1999: 1579-1588. [9] 唐卫明,孙红星,刘经南. 附有基线长度约束的单频数据单历元LAMBDA方法整周模糊度确定[J].武汉大学学报(信息科学版),2005,30(5):444-446. [10] 张书毕,刘鑫,宋冰,等.附有约束的BDS单频单历元改进型Par Lambda 算法[J].中国矿业大学学报,2017,46(1):201-208. [11] 王振杰,欧吉坤,柳林涛.一种解算病态问题的方法——两步解法[J].武汉大学学报(信息科学版),2005,30(9):821-824. [12] 隋春玲,谢建涛,于合理,等.基于GPS/GLONASS/BDS组合的单历元单频短基线RTK定位算法研究[J].测绘与空间地理信息,2015,38(10):154-157. [13] 谢建涛,郝金明,于合理,等.基于BDS/GPS的短基线单历元多频RTK定位研究[J].全球定位系统,2016,41(1):6-13. [14] 祝会忠,高星伟,秘金钟,等.一种GPS整周模糊度单历元解算方法[J].测绘科学, 2011,36(4):9-11. [15] 刘根友,欧吉坤.GPS单历元定向和测姿算法及其精度分析[J].武汉大学学报(信息科学版),2003,28(6):732-735. [16] TEUNISSEN P J G. An analytical study of ambiguity decorrelation using dual-frequency code and carrier phase[J]. Journal of Geodesy, 1996, 70(10):515-528. [17] 王拓. 北斗精密相对定位与测速技术研究[D].郑州:信息工程大学,2012. [18] KROES R. Precise relative positioning of formation flying spacecraft using GPS[D].Delft: Nederlandse Commissie Voor Geodesie Netherlands Geodetic Co-mmission,2006:110-113.
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