区域对流层延迟建模分析

发布时间：2018-04-11 18:57

本文选题：GPS定位精度 + 对流层延迟　；参考：《中南大学》2013年硕士论文

【摘要】：对流层延迟是制约GPS定位精度提高的主要误差源之一。在实际测量工作中,通常采用模型法进行消除,但是由于气象代表性误差及气象元素测定误差的影响,导致对对流层延迟的预测精度不高,并最终限制GPS的测量精度。差分测量在应用中也较常见,但在地形复杂多变,气象元素差异较大区域会带来很大的残余对流层延迟,对定位结果有很大影响。为提高小范围区域对流层延迟的预测精度,满足较高精度测量需求,本文对香港区域内的对流层延迟进行分析建模。具体工作如下： 1.对现有的对流层延迟处理方法进行总结和对比,简述其建立方法。 2.运用Bernese软件解算出香港区域CORS网12个基站多年的天顶对流层延迟值,对其在时间上的变化规律进行分析,得出各个基站的天顶总延迟值具有年周期特性。根据该区域各基站天顶总延迟值在空间上的梯度变化值,建立起基于BP神经网络的区域对流层延迟时空模型,并与现有的经验模型进行对比。 3.通过对香港区域干湿延迟的时空分析,得出其具有不同的时空特征,根据干湿延迟不同特征,建立起相应的干湿延迟时空模型,并与现有的经验模型进行对比。 4.为证明所建立模型的有效性,利用新模型以及现有的定位程序实现对观测数据的预处理功能,最终通过定位表明新模型比现有模型的定位精度提高2厘米左右。 5.简要分析了在一些特殊天气条件下对流层干湿延迟随气候变化情况,并得出了一些有益的结论。图24幅,表21个,参考文献66个。
[Abstract]:Tropospheric delay is one of the main error sources that restrict the accuracy of GPS positioning.In the practical measurement work, the model method is usually used to eliminate it, but because of the influence of the meteorological representative error and the measurement error of meteorological elements, the prediction accuracy of tropospheric delay is not high, and the precision of GPS measurement is limited.Differential measurement is also common in application, but in the complex terrain, the difference of meteorological elements will bring a large residual tropospheric delay, which has a great impact on the location results.In order to improve the prediction accuracy of tropospheric delay in a small area and to meet the requirement of high precision measurement, the tropospheric delay in Hong Kong region is analyzed and modeled in this paper.The specific work is as follows:1.The existing tropospheric delay processing methods are summarized and compared.2.The zenith tropospheric delay of 12 base stations in Hong Kong CORS network is calculated by using Bernese software. The variation law of the time is analyzed and the annual periodicity of the total zenith delay of each base station is obtained.According to the spatial gradient of the total zenith delay of each base station in this region, a time-space model of regional tropospheric delay based on BP neural network is established and compared with the existing empirical model.3.Through the spatiotemporal analysis of dry-wet delay in Hong Kong, it is found that it has different space-time characteristics. According to the different characteristics of dry-wet delay, the corresponding space-time model of dry-wet delay is established and compared with the existing empirical model.4.In order to prove the validity of the established model, the preprocessing function of the observed data is realized by using the new model and the existing positioning program. Finally, the positioning accuracy of the new model is improved by about 2 cm compared with the existing model.5.In this paper, we briefly analyze the variation of dry-wet delay in troposphere with climate under some special weather conditions, and draw some useful conclusions.There are 24 figures, 21 tables and 66 refs.
【学位授予单位】：中南大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：P228.4

【参考文献】