1、 摘 要 在全国大力发展北斗卫星系统的大环境下,研究北斗卫星的精确定位方法成为热门。本文重点介绍了一种在北斗卫星的先进的三频信号的基础上进行的载波相位模糊度解算的 CIR方法。在保证精度的同时,简单快速地进行运算。 本文 所做的工作主要有 四 个方面: 1、进行 北斗三频 载波相 位最优组合的求解。使用函数极限的原理进行载波组合的解算,给出了理论推导,并选择了诸多优秀的载波组合,为 CIR 算法提供了理论基础 。 2、进行基于北斗 系统 的三频模糊度解算的编程 实现。运用 CIR 算法,在 matlab 平台上进行编程 , 主要功能包括 读取 rinex 3.0 格式 数据、 解算卫星轨道位置
2、 、单点定位求近似坐标以及 用三频载波双差模糊度求解 短基线向量。 程序是基于 GPS 的 程序进行调整、新增,以便完成上述功能。 3、 运用程序 处理北斗数据,实际进行运算 , 采集 获得基线向量 的结果, 比较 精度 。 数据处理要保证在数据正确的情况下进行, 结果要进行检验。 4、 由 CIR 算法 分析每一步的误差传递 ,选取优秀的伪距组合 、相位组合 , 通过数据处理结果, 证实算法的可行性。 本文的前提条件是 中 短基线向量,因此 , 双差后忽略了大气延迟的影响, 而 长基线应当考虑 在内, 并且对于所得定位结果的 X、 Y、 Z 轴分量变化 趋势 本文没有进行 研究。今后 研究的
3、重点将针对以上不足,完善理论,优化程序,加强功能。 关键词: 卫星导航定位 ; 北斗 ; 模糊度 ; 三频 ; CIR ABSTRACT In the environment of the country developing the Beidou satellitesystem rapidly,the research about Beidou satellite precise positioninghas become hot. This article focuses on an advanced tri- frequency signal on the basis of the Be
4、idou satellite carrier Integer ambiguity resolution CIR. Operator need be simple and quick while ensuring the accuracy. I work mainly in four aspects: 1.The solves the optimal combination of carrier phase.Using the principle of limit of a function solves carrier combinations. Theoretical derivation
5、is given and good combinations has been chose. 2.The article programs and achieves tri-frequency integer ambiguity resolution based Beidou system. Using CIR algorithm,I encode in matlab platform. The computer programs have some functions,which include reading rinex 3.0 format data, solving satellite
6、s orbits,single-point position getting the approximate coordinates and striking short baseline vectors with solving the double difference carrier ambiguity of tri-frequency. 3.With processing COMPASS data,I conduct the actual operations. The end result is the base- line vector, comparing precision.
7、During data processing,ensure that the data is correct in the case. The results should be tested. 4.The pseudorange combinations of the first step in the algorithm of the CIR are analysised to calculate error propagation at each step.Then I select the better combination of pseudorange and phase ,con
8、firming its feasibility with the results. The prerequisite of the article is for a short baseline vector, so double difference can ignore the atmospheric delay effects,which the long baseline should include,and for the positioning results, the trends of X, Y, Z axis component has not been studied. Thus,future research will focus on the shortcomings above, improving the theory, optimization procedures, and enhance functions. Key words:Satellite navigation and positioning;Compass;Ambiguity;tri-frequency;CIR