The Near Real-Time Estimation Of Precise Satellite Clock Bias

With the continuous development of the science and technology and human society, people are demanding measurement technology increasingly, but the measuring technology has been rapid progress with the development of the era, especially in the development of satellite navigation and positioning system.GPS technology has a wide range of applications relatively in various industries now,with the advent of precise point positioning technology, and it extends the development and range of GPS applications more. However, precise point positioning,it needs to consider more errors and to correct more, and its positioning principle uses interpolation precise satellite orbit and clock bias release of global IGS precise satellite service center,to obtain the corresponding sampling interval orbital data and clock bias data, but by the limitations of the accuracy and real-time of the precision satellite clock bias, because the corresponding service data released by IGS has a certain time lag, so in order to carry out real-time precise point positioning, satellite clock bias and satellite orbital data must be determined in real time,which is a hot issue being studied abroad now, so it has important research value and significance for the study on near real-time satellite clock bias.Purpose of this thesis is to study the near real-time estimation of precise satellite clock bias, discover a more mature, reliable estimation model and solver methods. Through the exhaustive study, research and analysis of the precise satellite clock bias for near real-time estimation.Based on the continuous operation reference station data of Hong Kong and IGS surrounding the Hong Kong observatory data as raw data, based on the non-differential model of ionospheric elimination combination observations, and to estimate the influence effect of the error, troposphere delay error, antenna phase deviation, earth rotation correction and other various modeling and estimation error, and in view of two methods of the receiver clock,we use kalman filter to calculate satellite clock error respectively, calculate the clock difference of comparison with the precise satellite clock provided by IGS, its difference of the absolute precision clock bias can reach about0.5-1ns, at the same time,also compared and analyzed with the satellite clock bias solved by the Bernese software, the calculating results are obviously higher than that of results of the the Bernese software, and the Bernese software was also used to study affection of the accuracy of the calculating results of satellite clock bias by the different reference station data selection. Based on the the clock estimated above and more reliable information source,we can realize the high accuracy real-time precise point positioning,it can provide reference and practical service, this thesis research method has a certain practical value.