A Dual-Frequency Combined Ambiguity Fixed Method for Mobile Communication Base Station

The carrier phase has a higher positioning accuracy than the pseudorange measurement value, and the dual-frequency combined observation is an effective method to eliminate the observation error and fix the carrier ambiguity. However, in the base station positioning scenario, the accuracy of clock synchronization between base stations is not high, and there is a strong correlation between clock deviation and carrier phase ambiguity, which limits the convergence speed and success rate of traditional ambiguity fixed methods. For this reason, this paper proposes a center iterative optimization (CIO) ambiguity fixed algorithm based on dual-frequency combination, which eliminates the influence of base station and receiver clock deviation through dual-frequency combination of carrier phase observations. The dual-frequency ambiguity mapping relationship is established, and the objective function is determined according to the posterior probability of the ambiguity and the center distance weighting matrix, and finally the optimal value of the ambiguity is obtained by searching within the constraint condition. The simulation results show that the ambiguity fixed speed and the fixed success rate of the algorithm proposed in this paper are increased by more than 33.3% and 6.3%, respectively, compared with the traditional Bootstrapping algorithm and the LAMBDA algorithm.