POS system double-strapdown calculating post-processing method based on R-T-S smoothness

Abstract

The invention discloses a POS system double-strapdown calculating post-processing method based on R-T-S smoothness. According to the method, firstly, carrier phase differential GPS data and inertial data are utilized to perform strapdown calculating and Kalman filtering to obtain a combined filtering value of GPS sampling points and corresponding filtering parameters, then reverse R-T-S fixed interval smoothness is performed on the filtering parameters to obtain an error correction value of the Kalman filtering parameters, the value is utilized to correct the strapdown calculating value of the GPS sampling points, and smooth output of the GPS sampling points can be obtained. The double-strapdown calculating method based on R-T-S smoothness is adopted between every two adjacent GPS sampling points, and POS system output accuracy between the GPS sampling points is improved. The POS system double-strapdown calculating method based on R-T-S smoothness has the advantages that the POS system output accuracy between the GPS sampling points and the output accuracy between the filtering intervals are improved at the same time, and post-processing for output accuracy of the POS system can be effectively improved particularly under the condition of GPS signal lock losing.

Description

technical field [0001] The invention relates to a post-processing method for improving the output precision of the POS system. The method uses the R-T-S smoothing method to correct the Kalman filter parameters and improves the POS output precision of each GPS sampling point. On this basis, the two-way strapdown solution is used to improve the The POS output accuracy within the filter interval. Background technique [0002] The Position & Orientation System (POS) provides high-precision position, velocity, and attitude information for remote sensing loads for motion error compensation. POS usually consists of an inertial measurement unit (Inertial Measurement Unit, IMU) and a global satellite positioning system (Global Position System, GPS), which is essentially a combination based on SINS (Strapdown Inertial Navigation System) and GPS (Global Positioning System) The navigation system is a complementary motion information measurement system realized by utilizing the high lon...

AI Technical Summary

Problems solved by technology

[0005] The problem solved by the technology of the present invention is: aiming at the problem that the Kalman filter has low estimation accuracy of error parameters when the observability of the system error state is not high, the R-T-S smoothing method is used to improve the reliability of the system error state by using all the observation data of the entire flight operation Observation degree, to obtain the best estimate at the GPS sampling point

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