Research On Attidude Measurement Of The Carrier Based On Multi-constellation Integrated System

The research on attitude measurement using the carrier phase signals of the multi-consatellation integrated system is a new direction of studies.In this paper,attitude measurement of the carrier based on multifrequency observations of the multi-consatellation is studied.The features of attitude measurement of the carrier using multifrequency phase observation signals are summarized.The key technologies of attitude measurement based on the multi-consatellation integrated system are researched,and analyse the improvement and optimization to improve speed and precision of the attitude measurement of the carrier.In this paper,the GNSS obversation models of the attitude measurement system are studied,the principle of the mulitfrequency carrier phase combination is summarized,and the error characteristics of the carrier attitude measurement system are analysed,this is a part which provide theory basis for the follow-up work and study.Combined system in the constellation of multi-carrier signal is initially observed ambiguity of the solution method. This method of TCAR LAMBDA method is studied, and were simulated and analyzed their advantages and disadvantages.The methods that are used to fix the initial carrier phase ambiguity using the carrier phase obversations of the GNSS are studied.A method that is the TCAR based on the search method of the LAMBDA is advanced.The method that combinate the anvances of the TCAR and the LAMBDA is used to solve the carrier phase ambiguity of the double differenec.According to the steps of TCAR,the search method of the LAMBDA is added in every step.The measurement accuracy of pseudorang is improved gradually.The carrier phase ambiguity of the double difference can be solved in signal epoch.The method overcomes the limitations of traditional methods and can fastly calculate the initial carrier phase ambiguity.In the cases of the satellite number of the multi-constellation intergated system,A method of the satellite selection algorithm based on azimuth/elevation can choose the satellites which have better positional characterictics of a certain number satellites.Those satellites can use to calculate the carrier phase ambiguity in signal epoch and improve the ambiguity algorithm for calculating speed.Multi-frequency observations of the phase requirements under the law and bad pseudorange / phase combination method cycle slip detection and repair.Using the method of pseudorang/phase combination to detect the cycle slip is studied.According to the multifrequeny characteristics of the mulit-consatellation intergated system, the application of the combination obversation in aspect of detection and reparation of the cycle slip is studied.According to the combination of obversation principles,choose the combination obversations which have a long wavelengths,can slack the ionosphere error and whose coefficient is irrelevant.The cycle slip of the long wavelengths obversation can be detected using the method of pseudorang/phase combination.Then the cycle slip of the basic carrier phase can be obtained according to the cycle slip of the long wavelengths obversation.Solution of the vector attitude algorithm, the main analysis of the QUEST algorithm combined system in a multi-carrier constellation of attitude algorithm.In the event of single consatellation system,double consatellation intergated system and multi-consatellation intergated system,using the single frequency and multifrequency to calculate the attitude of the carrier is studied and the precisions of cacluating the attitude of the carrier are analysed and compared.According to keep out environment tha the visilbe satellite number is less,the difference caculating the attitude between the single consatellation system and the multi-consatellation intergated system is compared.It shows that the multi-consatellation intergated system is better than the single consatellation system.Based on the above study, a multi constellation composite systems simulation platform vector attitude algorithm, the simulation of the motion vector for all aspects of track and verify the feasibility of the algorithm.