The Research Of Gps Measurement Data Post-processing Method

This issue is from the key projects in Tianjin Science and Technology Support Program (09ZCGYSF00300) " Research of Speed Secure Real-time monitoring system for measuring traceable calibration standards "With China's rapid economic and social development, road traffic situation is not optimistic, how to control traffic flux and limit vehicle speed have become the important part of real-time monitoring system in Tianjin, they need real-time detection speed, real-time detection speed measurement calibration and trace to the source needs speed real-time monitoring of measurement traceable calibration standard. To achieve the modernization of Tianjin urban transport and sustainable development goals, to research the establishment of a speed test measurement standards is imminent.GPS (Global Positioning System) is by far the most complete precision satellite navigation and positioning system. The most important application of GPS is the location and speed, while in the the process of location and speed, it is subject to the impact of various error sources, making the accuracy of positioning and speed be greatly affected, GPS receiver uses some hardware and software ways to compensate for impact in the process of signal transmission, but this approach can only compensate for part of the errors, and the user can not intervene. The so-called post-processing of the data is to get accurate results by using computer to handle data in various ways.This work includes:(1) After the research of the basic principles of GPS and Kalman filtering theory highlighting the NMEA-0183 Sentence Format as well as how to set up Lassen(?) iQ GPS receiver, in order to experiment laid a theoretical basis.(2) Designed static positioning experiments, in static positioning, the selected time and weather conditions are good, and the space is open around the antenna, the error sources affecting the positioning accuracy are very small, the real measured positioning accuracy fluctuates within 1m. After Kalman filtered, C/A code Lassen(?) iQ GPSreceiver positioning accuracy to 0.1m, precision can be improved by an order of magnitude.(3) Simulated the dynamic process of car sport, in dynamic simulation, through the Kalman filter processing, the obtained trajectory can basicly reflect the car's true trajectory; X direction of filtering error mean and standard deviation curve has a larger error in the beginning, as the observation time increases, the error gradually decreases; Compared with the X direction estimation error, Y direction estimation error mean value volatiles more greatly, which is due to the speed component in the Y direction.