GPS/INS integrated navigation attitude determination method based on CLAMBDA and AFM aided by INS

To improve the success rate and performance of global positioning system (GPS) attitude determination, an attitude determination method is proposed, which combines the constrained least squares ambiguity decorrelation adjustment (CLAMBDA) and ambiguity function method (AFM), and makes use of the inertial navigation system (INS) attitude information. In the process of CLAMBDA, the INS information is combined with the GPS carrier phase and code measurements, increasing the redundancy of equations to solve the float solution, and then searching the fixed solution. If the true ambiguity solutions are not found and the attitude is false, the false attitude is replaced by the attitude using AFM. Meanwhile, the INS information is used to shrink the search space of AFM. After that, the integrated filter of GPS/INS is made. Through the land vehicle experiments, compared with the original algorithm, the proposed algorithm can effectively improve the success rate of attitude determination.