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Title Analysis of the quality of GPS positioning for busses in urban areas
Author Borcher, Henrik
Supervisor Jørgensen, Rene Munk (Logistics and Intelligent Transport, Department of Transport, Technical University of Denmark, DTU, DK-2800 Kgs. Lyngby, Denmark)
Jensen, Anna B.O. ([affiliation name could not be established])
Zabic, Martina (Department of Transport, Technical University of Denmark, DTU, DK-2800 Kgs. Lyngby, Denmark)
Institution Technical University of Denmark, DTU, DK-2800 Kgs. Lyngby, Denmark
Thesis level Master's thesis
Year 2008
Abstract The aim of this dissertation is to analyze and improve the public bus navigation system implemented by Movia and developed by Swedish Hogia. Today, all vehicles operating on A-routes in Copenhagen are equipped with GPS receivers and mechanical measuring units. An application is implemented to simulate the bus movement and estimate the accuracy and integrity of the system. The accuracy is determined based on statistics, mathematics and mapping tools such as Google Earth. The application is constructed with options allowing the user to choose between dierent dates and time ranges on each day. One can similarly investigate specic time windows or road segments on the 5A route. The evaluation is two fold; bus station and bus motion analysis. The stations are ideal for position accuracy determination while passengers are serviced as the bus comes to a complete stop. The motion impact on the bus sensors will illustrate how well the system performs in transit e.g. at dierent speeds or multipath environments. Based on more than 6000 observations the optimal precision is about six meters acquired primarily at bus stations. The correlation between system performance during motion and density of buildings is signicant. The suburb segments achieve near-optimal accuracy while inner city observation deviates with up to 70 meters. Improvements are presented at the end of the project to both increase accuracy and improve integration of the public bus navigation system.
Admin Creation date: 2008-10-13    Update date: 2008-11-11    Source: dtu    ID: 224463    Original MXD