DGPS/INS Integrated Position And Attitude Determination And Its Application In MMS

It's increasingly difficult for the data acquirement and update to meet the requirement, while the traditional surveying growing into the spatial information science represented by GPS, RS and GIS. As a new typical mapping technology, MMS (Mobile Mapping System) can resolve this issue efficiently.In MMS, one of the most important models is the positioning and orientation of the photogrammetry platform, which focus on how to calculate directly the position and attitude information with GPS, INS, etc. sensors, and is also the research hot point currently. Compared with the traditional method needing ground control point, the direct reference method has great superiority, which combines the theories of various fields and can provide a complete new way for the acquirement of exterior elements of photogrammetry platform.This dissertation is mainly focused on the data processing models for GPS, SINS and DR, as well as systematical discussion on the GPS/INS/DR integration theory and proposed the corresponding solutions regarding the implement of high precision positioning and orientation of photogrammetry platform in MMS. The most important contribution this dissertation presents is that the high precision GPS/INS/etc. sensors integration theory has been systematically introduced into the survey field for the first time and has been applied to a new survey technology -MMS, and during the research, a series of creative theories and methods has been proposed. The main work and innovations done by the author are presented as follows:1. The author deduced firstly the single point, single differenced and double-differenced positioning models with the linear equations, explained the processing methods and results corresponding to various models and various data type. Point out that the results will be the same for the single epoch positioning in single differential model or double differential model using least square method. The conclusion shows that using double differential model in Kalman filter can reduce the process for receivers clock errors, as well as the advantage of more simple data processing comparing to single differential model. Proposed that the receivers clock errors and receivers carrier phase bias cannot be processed separately, explaining the reason of the difficult of high precision GPS time comparison during short time. Described the integer characteristic of the phase ambiguity in the double differential model, which is the theory fundamental base for ambiguity resolution in this paper.2. Discussed the GPS velocity measurement method emphasized in the Doppler observation. For the first time deduced the Doppler single point, single differential and double differential velocity equations with linear equation. Analyzed the main error sources of GPS Doppler velocity measurement, and discussed the accuracy, efficient and value of the differentia] velocity measurement The author points out for the first time that the Doppler velocity measurement of single differential model using least square method will lead to the same result as that of double differential model. Because the design matrix and random model in the GPS Doppler velocity measurement equation are the same with those in GPS differential position, so they have similarstatistic characteristic, i.e. both GPS Doppler velocity measurement and GPS position are affected by the GPS satellites distribution and observation noise.3. The author systematically studied and summarized the current on-the-fly (OTF) GPS ambiguity methods, cataloged the various OTF methods according to observation space, coordinates space and ambiguity space. Especially attention has been place on the LAMBDA method, whose theoretic precondition, core technology and practical contribution have been concluded in this paper.4. On the basis of analyzing the current OTF method, according to the inner relationship and statistic characteristic of dual frequency phase observation, the author proposed a new method - Dual Frequency Correlation Method (DUFCOM), which is indep...