Integrated GPS/GLONASS/BeiDou Autonomous Positioning: Method and Performance Analysis

• Main Authors: Yi-ChingYeh, 葉怡靖
• Other Authors: Ming Yang
• Format: Others
• Language: en_US
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/39c63m

碩士 === 國立成功大學 === 測量及空間資訊學系 === 105 === With the developments of satellite positioning technology, the demand for high-quality navigation service is increasing. However, the technology is easily affected by limited satellite visibility and poor satellite geometry, especially in obscured areas. In order to provide continuous global positioning capability, the usage of multiple GNSS constellations is an effective method for solving the visibility and geometry problem thanks to the increased number of visible satellites. Thus, the goal of this study is to propose a method of integrating GPS, GLONASS, and BeiDou systems for improved autonomous navigation as well as to analyze the improved performance. In addition, a variety of observational conditions are simulated by adjusting satellite cut-off elevation angles. The Pope Tau test is adopted for data blunder detection to prevent the solution from being affected by outliers; furthermore, the Helmert variance component estimation (VCE) is applied to properly model the weighting of the heterogeneous data from different satellite systems. The results show that the VCE is effective in improving positioning accuracy. Moreover, multiple GNSS is adopted so that the GPS/GLONASS/BeiDou integrated system is capable of providing sufficient visible satellites and strengthened satellite geometry. Consequently, the positioning accuracy of the integrated system is greatly improved especially in the obscured environments. It can be known that it is essential to use multiple GNSS in urban or signal-blocked areas so as to ensure the users good autonomous navigation service.