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How to fix integer ambiguity quickly and accurately is a key problem in carrier phase measurement. In order to improve the search rate of integer ambiguity, a integer ambiguity resolution algorithm based on beetle antennae colony search (BACS) algorithm was proposed. Through the comparison experiment with BAS algorithm, Bas-Nadam algorithm, LAMBDA algorithm and MLAMBDA algorithm, the solution rate and stability of the three-dimensional ambiguity solution were carried out. When the success rate of the solution of BACS algorithm was equal to that of LAMBDA and MLAMBDA algorithm, it can use less time to search the optimal ambiguity solution. In order to verify whether BACS algorithm is applicable in the case of high-dimensional ambiguity solution and engineering solution, the experiments of high-dimensional ambiguity solution and the application experiments of BACS algorithm under single frequency and single GPS system were carried out. The analysis and experiment show that BACS algorithm can guarantee the real-time performance and robustness of high-dimensional ambiguity solution. For 12-dimensional ambiguity solution, the average solution time is 0. 068 seconds and the success rate is 92% . For low-dimensional ambiguity solution, the solution rate is faster and the success rate is higher. In the engineering calculation of single frequency single GPS system, the positioning accuracy of x, y and z directions is ± 0. 008 meter, ± 0. 01 meter and ± 0. 01 meter respectively, which can reach centimeter-level precision positioning. [ABSTRACT FROM AUTHOR]

Aiming at the problem of low reliability of real-time ambiguity fixation in kinematic-to-kinematic relative positioning based on single-frequency carrier phase, a DGNSS / INS-based smoothed INS-aided ambiguity resolution strategy for kinematic-to-kinematic relative positioning was proposed, to improve the universality of high precision positioning for low cost receivers. Firstly, a kinematic-to-kinematic relative positioning model was established based on double-difference (DD) pseudorange and carrier phase observations. Secondly, a Kalman filtering was applied to the inertial navigation data, and the DD observation equations were reconstructed using the prediction pseudorange by filtered INS-derived position. Meanwhile, the INS-derived position constraint equation was complemented. The high precision ambiguity float solutions and their covariance matrix were obtained, then LAMBDA algorithm was used to fix the ambiguity and ratio test was conducted. Finally, the INS errors were feedback corrected by DGNSS / INS tightly coupled Kalman filtering results to maintain INS high precision navigation. The experimental results of testing data show that the method adopted can effectively increase the accuracy of ambiguity float solution, reduce the search space for ambiguity, and improve the success rate of ambiguity fixation. By comparing the results of without INS aided, with INS aided and with smoothed INS-aided, the success rate of the three methods were 92. 3%, 99. 1% and 99. 6%, respectively, and finally achieve dynamic relative positioning in centimeters. [ABSTRACT FROM AUTHOR]