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用遗传算法搜索GPS单频单历元整周模糊度 总被引:10,自引:2,他引:10
介绍了短基线利用单频单历元双差载波相位定位时模糊度固定的基本理论,探讨了利用遗传算法快速搜索GPS单频单历元整周模糊度的一些理论和实现的方法.提出了用改进的正则化方法改善浮动解来提高搜索成功率的新思路。算例分析表明,在一定的条件下.应用遗传算法搜索整周模糊度成功率高、稳键性较好。 相似文献
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针对不存在先验信息时常规GPS单历元数据处理中存在的问题,提出了一种新的GPS整周模糊度单历元算法.该算法先采用一个历元的码观测值进行最小二乘定位,求取初始模糊度,并根据解的中误差来构造模糊度原始搜索空间,再采用两种不同线性组合的扩波方法进行模糊度变换,使原模糊度的搜索空间变小.在模糊度的新搜索空间确定后,通过线性组合的逆变换求取模糊度N1及N2,并以模糊度函数法进行真值的搜索,实现单历元解算.采用基线长度不同的两组数据测试,结果表明了本文方法的可行性和可靠性. 相似文献
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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%。 相似文献
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顾及GEO卫星约束的长距离BDS三频整周模糊度解算 总被引:1,自引:0,他引:1
长距离BDS三频载波相位整周模糊度解算受大气误差残余的影响较大,GEO卫星相对于地球静止也非常不利于载波相位整周模糊度的解算。利用GEO卫星的信号传播路径相对较稳定、大气延迟误差的影响不随卫星空间位置变化的特点,对GEO卫星进行更符合实际情况的大气延迟误差约束研究。利用GEO卫星B2和B3载波相位整周模糊度线性关系,降低测站差分电离层延迟误差残余对模糊度备选值的影响,进行B2和B3载波相位整周模糊度备选值的选择。通过三频载波相位整周模糊度间不包含观测误差影响的线性关系对模糊度备选值组合进行检测,并对模糊度搜索空间进行约束。利用历元间GEO卫星的模糊度备选值判断历元间电离层延迟误差残余的变化,对GEO卫星的参数估计进行更符合实际情况的约束。研究了顾及GEO卫星实际大气延迟变化和整周模糊度约束的长距离BDS三频载波相位整周模糊度解算方法。提出了利用历元间模糊度备选值确定电离层延迟约束值的方法,对GEO卫星历元间随机游走的约束值进行符合实际情况的调整。试验结果表明,本文的方法能够提高三频载波相位整周模糊度解算的效率和测站位置的精度。 相似文献
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BDS网络RTK中距离参考站整周模糊度单历元解算方法 总被引:1,自引:1,他引:0
提出了一种BDS网络RTK中距离(50~100 km)参考站间的双频载波相位整周模糊度单历元解算方法。该方法首先利用B1、B2载波相位整周模糊度间的线性关系选取B1、B2载波相位整周模糊度备选值。利用双频载波相位整周模糊度备选值计算双差电离层延迟误差,根据参考站各卫星电离层延迟误差间的空间关系,使用双差电离层延迟误差构建双差电离层延迟误差的线性计算模型。通过双差电离层延迟误差线性计算模型的建立搜索和确定B1、B2载波相位的整周模糊度。经CORS网实测数据试验算例的验证,该方法只需一个历元的观测数据即可确定参考站间双差B1、B2载波相位整周模糊度,且不受周跳影响。 相似文献
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长距离网络RTK基准站间整周模糊度单历元确定方法 总被引:2,自引:1,他引:1
提出一种长距离(100~200km)网络RTK基准站间的整周模糊度单历元确定方法。该方法首先利用载波相位模糊度间的线性约束关系对双差宽巷模糊度进行搜索。为了减小非弥散误差残差对载波相位模糊度解算的影响,采用了一种新的根据高度角重新选择基准卫星的方法。然后根据双差宽巷模糊度选取双频载波相位模糊度的备选组合,利用基准站间非弥散误差残差的计算值对双差载波相位模糊度进行搜索和确定。经试验算例的验证,该方法快速、稳定,不受周跳影响,只需一个历元的观测数据即可确定长距离基准站间的双差整周模糊度。 相似文献
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首先指出了基于传统的假设检验理论的三步法在评价模糊度整数解正确性时存在的理论缺陷,然后介绍了模糊度归整域的概念和可容许整数估计的定义,并在可容许整数估计原定义的基础上给出了更为严密的新定义。最后,基于这个可容许整数估计的新定义,讨论了模糊度成功率的概念及其计算公式。从理论上讲,只有模糊度的成功率才是评价模糊度整数解正确性的严密尺度。 相似文献
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A new approach to GPS ambiguity decorrelation 总被引:13,自引:1,他引:12
Ambiguity decorrelation is a useful technique for rapid integer ambiguity fixing. It plays an important role in the least-squares
ambiguity decorrelation adjustment (Lambda) method. An approach to multi-dimension ambiguity decorrelation is proposed by
the introduction of a new concept: united ambiguity decorrelation. It is found that united ambiguity decorrelation can provide
a rapid and effective route to ambiguity decorrelation. An approach to united ambiguity decorrelation, the HL process, is
described in detail. The HL process performs very well in high-dimension ambiguity decorrelation tests.
Received: 9 March 1998 / Accepted: 1 June 1999 相似文献
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整数相位钟法精密单点定位模糊度固定模型及效果分析 总被引:1,自引:1,他引:0
精密单点定位(PPP)模糊度固定方法有3种:星间单差法、整数相位钟法和钟差解耦法,但目前仅法国CNES公开发布用于整数相位钟法PPP模糊度固定的产品,因此研究基于整数相位钟法的用户端PPP模糊度固定模型很有必要.本文分析了整数相位钟法PPP模糊度固定模型,着重指出该模型与传统浮点解PPP模型的区别;提出一种顾及质量控制的逐级模糊度固定策略用于具体实施PPP模糊度固定.大量动态PPP解算试验表明:与浮点解PPP相比,固定解PPP具有更快的收敛速度且定位精度和稳定性更好. 相似文献
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Penalized GNSS Ambiguity Resolution 总被引:1,自引:1,他引:1
P. J. G. Teunissen 《Journal of Geodesy》2004,78(4-5):235-244
Global Navigation Satellite System (GNSS) carrier phase ambiguity resolution is the process of resolving the carrier phase ambiguities as integers. It is the key to fast and high precision GNSS positioning and it applies to a great variety of GNSS models which are currently in use in navigation, surveying, geodesy and geophysics. A new principle of carrier phase ambiguity resolution is introduced. The idea is to give the user the possibility to assign penalties to the possible outcomes of the ambiguity resolution process: a high penalty for an incorrect integer outcome, a low penalty for a correct integer outcome and a medium penalty for the real valued float solution. As a result of the penalty assignment, each ambiguity resolution process has its own overall penalty. Using this penalty as the objective function which needs to be minimized, it is shown which ambiguity mapping has the smallest possible penalty. The theory presented is formulated using the class of integer aperture estimators as a framework. This class of estimators was introduced elsewhere as a larger class than the class of integer estimators. Integer aperture estimators, being of a hybrid nature, can have integer outcomes as well as non-integer outcomes. The minimal penalty ambiguity estimator is an example of an integer aperture estimator. The computational steps involved for determining the outcome of the minimal penalty estimator are given. The additional complexity in comparison with current practice is minor, since the optimal integer estimator still plays a major role in the solution of the minimal penalty ambiguity estimator. 相似文献
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Precision, volume and eigenspectra for GPS ambiguity
estimation based on the time-averaged satellite geometry 总被引:1,自引:1,他引:1
P. J. G. Teunissen 《Journal of Geodesy》1997,71(5):290-301
In this contribution we consider the
time-averaged GPS single-baseline model and study in a qualitative sense its
relation with the geometry-free model and the geometry-based model. The
least-squares estimators of the model are derived and their properties
discussed. Special attention is given to the ambiguity search space, since it
plays such a crucial role in the problem of integer ambiguity estimation and
validation. Easy-to-evaluate, closed-form expressions are presented for the
volumes of the ambiguity search spaces that belong to the geometry-free model,
the single-epoch geometry-based model and the time-averaged model. By means of
an eigenvalue analysis, the geometry of the ambiguity search spaces is revealed
and its impact on the search for the integer least-squares ambiguities
discussed.
Received: 3 April 1996; Accepted: 6 January 1997 相似文献