Key Points of National Highway Data Acquisition on Scale of 1∶50,000 with Differential GPS TechniquesIn Concurrent Technical Consideration of National Railway Data Acquisition
Cheng Pengfei ①,Li Xiyin,Zhang Li ①,Chen Xiangyang ②,Feng Jianwei ②,Xue Feng ②( ①Chinese Academy of Surveying and Mapping,Beijing,100039),( ②The 3rd S&M Engineering Institute of Shaanxi Province,710054)
Problems are described that exist in data acquisition by using DGPS techniques in the establishment of highway layer of the National Fundamental Geomatics Database on scale of 1∶50,000. Methods to solve the problems are discussed as well. In addition, ideas for single-receiver positioning are brought up for the establishment of railway layer, which make use of resources of GPS precise ephemeris and satellite clock bias via INTERNET.