Application of Phase Smoothing Pseudo Range PPP/INS Tightly Coupled Technique in Improving the Results of Low Precision MEMS

Abstract:

In land surveying and engineering surveying, we need to obtain high precision navigation results. However, due to the inertial device costs less than a introduction, commonly used low precision inertial navigation equipment with tightly coupled GPS / INS integrated to get high precision navigation results. Many studies have improved the accuracy of error by using the UKF and CKF filtering algorithm, but it is still using the traditional pseudo code directly, the improvement effect is not obvious, and the disturbance is large. In this study, the PPP /INSmodel is improved by using the carrier phase smoothing pseudo range algorithm. Experimental results show that based on phase smoothing pseudo range PPP/INS tight coupled method, the position precision and the velocity precision for of the measured data of higher accuracy of MEMS and GPS receiver can get to a decimeter level and centimeter level. This coupling method has higher accuracy, stronger anti disturbance and Have a better convergence than the traditional C/A code. Based on different phase smoothing epoch number combination ，the accuracy and smoothing effect is also different, the larger smooth epoch number is, the better treatment effect it has and The higher precision it has. For high precision measurement, the equipment cost is saved. It has a practical significance meaning in the measurement of outdoor ground.