测绘学报

• 学术论文 •    

顾及有色噪声影响的CGCS2000下我国CORS站速度估计

蒋志浩1,张鹏1,秘金钟刘丽芬   

  • 收稿日期:2010-01-28 修回日期:2010-04-12 出版日期:2010-08-25 发布日期:2010-08-25
  • 通讯作者: 蒋志浩

Velocity estimation on the colored noise properties of CORS network in China base on the CGCS2000 Frame

  • Received:2010-01-28 Revised:2010-04-12 Online:2010-08-25 Published:2010-08-25

摘要: 本文研究基于计算获取的CGCS2000(中国大地坐标系统2000)下我国国家CORS(全球导航卫星系统连续运行参考站)网1999年至2009年坐标时间序列,首先采用主成分空间滤波方法(PCA)提取CGCS2000框架下国家CORS网坐标时间序列中公共误差( Common Mode Errors , CME)的时空特性。其次采用功率谱分析方法分析了空间滤波后的国家CORS站坐标残差时间序列的噪声性质,采用最大似然法定量估计了坐标残差时间序列中的有色噪声分量,最后采用加权最小二乘法评定了顾及不同噪声影响的CGCS2000框架下的国家CORS网年速度估值和实际精度。研究结果表明: 采用空间滤波方法可提高CGCS2000框架下国家CORS网成果的精确性和可靠性,空间滤波后北、东和高方向的平均坐标重复性相对于滤波前分别减小了26%、22%和46%,滤波前后国家CORS站高度方向平均振幅减少近73%。在CGCS2000框架下我国CORS站坐标时间序列中白噪声不是噪声的主要成分,白噪声、闪烁噪声和随机漫步噪声的噪声性质是国家CORS站坐标时间序列的基本特征;我国CORS站有色噪声在水平方向和高度方向以及南北方向和东西方向上均表现出一定的规律性,顾及有色噪声的速度误差估值比只考虑白噪声的速度误差估值一般大2~6倍,速度估值偏差一般在2%~10%左右。

Abstract: Abstract Based on the calculation of the coordinate time series of CORS network in China during the period from 1999 to 2009 base on the CGCS2000 frame, the paper proposes the adoption of spatial filtering algorithm based on principal component analysis (PCA) to extract the space-time characteristics of Common Mode Error (CME) in coordinate time series of CORS network in China base on the CGCS2000(Chinese geocentric 3D coordinate system). Secondly, the method of power spectrum analysis is applied to analyze the frequency spectrum characteristics of coordinate time series after spatial filtering and fitting, the noise characteristic of the residual coordinate time series are estimated quantitatively with the criterion of maximum likelihood estimation. Finally, it evaluates the annual speed evaluation and the actual accuracy of national CORS network under different color noise modes with the weight least squares method. The result shows the adoption of PCA method can promote the accuracy and reliability of CORS network base on the CGCS2000 frame, describes more precisely the movement characteristic of CORS network. The mean square error in the orientation of the north, the east and the height are reduced by 22%, 26% and 46% respectively after filtering. The white noise is not the main part of the noises in the coordinate time series of CORS network in China, while the white noise, flicker noise and random walk noise are the basic characteristics in the coordinate time series of CORS network, based on which can describe better the movement parameters of CORS network. The colored noise in CORS network is regular in the orientation of the horizon, the height, the North-South, the East-West. With the comparison of the consideration of the colored noise and the white noise, the change percentage of speed evaluation in CORS network is generally around 2%--10%, the error of the former is 2-6 times bigger than the latter.