Research On The Algorithms And Theory Of BDS Triple-frequency Data Processing

Based on the existing GNSS multi-frequency navigation and positioning technology,this paper studies the theory and method of BDS triple-frequency Data Processing in detail.The BDS non-difference observation model and the differential observation model are deduced and defined,and various errors and corrections are given by the type.The theory of triple-frequency combination observation is systematically combed.The multi-frequency pseudorange /carrier phase combination And the multi-frequency phase geometrical combination of two kinds of cycle detection and repair methods.Based on the analysis of some factors that limit the accuracy of medium-length baseline ambiguity resolution,an improved medium-length baseline triple-frequency ambiguity resolution Method,and verified and analyzed with the measured Beidou triode data.Finally.The following main results of this paper are summarized as follows:1.Geometric error,ionospheric error and combined noise error were studied in detail from the perspective of geometric relations.Finally,the search method and function were used to study the triad combination observation theory.Extreme value method,and gives the derivation process,with the combination of EWL and WL combined with the sum of the combined coefficients and the combination of the coefficients and the NL combination with the sum of the coefficients.2.In-depth study of the theory of multi-frequency pseudorange / carrier phase combination and multi-frequency phase geometric combination of two cycle-slips detection and repair,and the size of the cycle-slips,insensitive cycle-slips,continuous cycle-slips and other situations Made a detailed study.For the multi-frequency pseudorange / carrier phase combining method,this paper is combined with three linear unrelated pseudorange / phase combination observations to verify that it can detect only one week of the size of the small cycle-slips,the basic non-existent Sensitive multi-geometric combination method.Based on its non-pseudorange noise,it is sensitive to high sensitivity and easy to produce insensitive cycle slips.It is proposed to use two phase geometrical combinations and a triple-frequency pseudorange / Phase combination of the combined detection method,verified by the measured data,the method can basically achieve all the cycle-slips of full detection.3.The basic principle of the classical TCAR algorithm is deduced,and then the double residual ionospheric residuals of the ambiguity resolution under the long-baseline condition are studied deeply.The stability of the ionospheric delay on the WL / NL fixed success rate Affect the function curve.In order to solve the above problems,a new method of solving the three-frequency ambiguity is proposed.Finally,in order to analyze the performance of the classical TCAR and M-TCAR in the long baseline condition,five BDS triple-frequency baseline data are analyzed from four aspects: ionospheric delay,RMS,noise level analysis and AR success rate.It can be seen that the M-TCAR has obvious advantages in all respects compared with classical TCAR.