G3

The Qinghai-Tibet Railway is a key project during China's Tenth Five-Year Plan period. It will be the longest and most elevated
railroad built on highlands in the world. The construction and transport conditions are so complicated, such as permafrost, bitter
coldness, lack of oxygen and ecological fragility. Therefore advanced technical measures and methods have been used during the
construction. Furthermore, we have carried out Qinghai-Tibet Railway information management planning (QTIMP) based mainly on
the G3 technique integration: geographic information system (GIS), global positioning system (GPS), and global system for mobile
communication (GSM) to ensure safe transportation and prompt maintenance of Qinghai-Tibet .

School of Civil Engineering & Architecture, Beijing Jiaotong University, Beijing 100044, China - jwpeng@sina.com
b School of Electronics and Information Engineering, Beijing Jiaotong University, Beijing 100044, China –
bgcai@center.njtu.edu.cn

GPS & GLONASS

The Global Position System (GPS) and the Global Navigation Satellite System (GLONASS) are based on a satellite system. Much work has been carried out on a non-satellite positioning system using the existing Global System of Mobile Communications (GSM) infrastructure. This leads to a GPS-GSM positioning system that manufacturers claim to reliably locate a mobile phone down to resolutions of less than 125 m [3]. The requirement needed to achieve such a resolution with a GPS/GSM positioning system is to have three GSM base stations in a 30 km area. This requirement is difficult to obtain especially in rural areas. The work carried out in this paper is how to integrate Digital Audio Broadcast (DAB) transmitters with GSM base stations for positioning systems. This novel DAB-GSM hybrid positioning system can reach an accuracy of 40 meters.