GNSS/INS integrated positioning and directioning algorithm based on three-way Kalman filtering smoother

Abstract

The invention discloses a GNSS / INS integrated positioning and directioning algorithm based on a three-way Kalman filtering smoother.A GNSS obtains the position quantity by means of a carrier phase difference measured value, independent calculation of a strap-down inertial navigation system is adopted, a system noise covariance matrix and a state vector covariance matrix are given according to the precision level of an inertial navigation device, forward filtering is conducted, the estimation result at the moment of ending of the first time of forward filtering is taken as the initial information of inverse filtering, the estimation result at the moment of ending of inverse filtering is taken as the initial information of the second time of forward filtering, and smoothing is conducted on the estimation result of inverse filtering and the estimation result of the second time of forward filtering to obtain final position, speed and attitude angle information.Aftertreatment precision of GNSS / INS integrated navigation is improved, and precision during GNSS satellite malfunction and in the initial stage of data observation is improved especially.

Description

technical field [0001] The invention relates to the technical field of post-processing of high-precision GNSS / INS combined positioning and attitude measurement, in particular to a GNSS / INS combined positioning and orientation algorithm based on a three-way Kalman filter smoother. Background technique [0002] In the process of GNSS / INS combined positioning and orientation data processing, the focus of people's attention will vary with different application fields. , the data can be post-processed, and the corresponding accuracy requirements will be greatly improved. In urban canyons, common high-rise buildings, tunnels, overpasses and other buildings will block the signals of GNSS satellites, causing satellites to lose lock or more serious multi-path effects, reducing the quality of data. As a result, GNSS satellites cannot provide position information without time-accumulated errors. The original integrated navigation orientation mode will be transformed into an inertial n...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to provide a GNSS / INS combined positioning and orientation algorithm based on a three-way Kalman filter smoother, which effectively solves the problem of rapid parameter drift during IMU independent navigation due to GNSS data discarding, and improves the post-processing process of GNSS / INS combined navigation Accuracy levels in the medium, especially during GNSS satellite outages and at the beginning of observation data

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