PRECISION AND NOISE CHARACTERISTICS OF HIGH-FREQUENCY
GPS EPOCH-BY-EPOCH POSITIONING
1）Key Laboratory of Earthquake Prediction，Institute of Earthquake Science，CEA，Beijing 100036
2）First Crust Monitoring and Application Center，CEA，Tianjin 300180
3）College of Surveying and Geoinformatics，Tongji University，Shanghai 200092
Abstract Highfrequency observations of 12 Continuous Operational Reference System（CORS）GPS stations in Tianjin were processed with precise point positioning（PPP）and relative difference positioning（PRP）to estimate the absolute and relative epochbyepoch positions.The Modified sidereal filtering was used to correct multipath effect of highfrequency position time series.Positioning precision of PPP for east，north and vertical components are 7.3 mm，7.1 mm and 16.0 mm，respectively.The precision of PRP for east，north and vertical components are 5.0 mm，5.2 mm and 14.7 mm，respectively.Compare to PPP，the precision of PRP is improved as 1.3 mm to 2.3 mm.According to the power spectral density，the noise is not only white noise.For PPP，the noise at frequencies below 0.1 Hz decreases with frequency and becomes flat at higher frequencies.However，for PPP，the noise at whole frequency band decreases with frequency.The difference of noise between PPP and PRP occur at high frequencies up 01HzAnd then，the spectral indexes of power law noise are estimated simultaneously with amplitude of white noise using maximum likelihood estimation.The white noise amplitude of PRP is much larger than PPP’s.The noise of PRP can be best described by a combination of white noise plus random walk noise.However，the noise of PPP can be best described by a combination of flicker noise plus white noise.
Su Xiaoning,Meng Guojie,Hu Xinkang et al. PRECISION AND NOISE CHARACTERISTICS OF HIGH-FREQUENCY
GPS EPOCH-BY-EPOCH POSITIONING[J]. jgg, 2014, 34(2): 150-154.
Su Xiaoning,Meng Guojie,Hu Xinkang et al. PRECISION AND NOISE CHARACTERISTICS OF HIGH-FREQUENCY
GPS EPOCH-BY-EPOCH POSITIONING[J]. jgg, 2014, 34(2): 150-154.
