Research And Implementation Of Local Vehicle Location System In Mountain Tunnels

In the mountain area whose road network includes a lot of tunnels,vehicles can not find the positioning GPS signal.And also the mobile communication network is not available.All the above situations make the vehicle dispatch and management difficult.The research purpose of this subject is to build an effective local positioning system in the tunnels road network in the mountain area,which will make it possible to send the position of vehicles to the monitoring center after they enter tunnels.Positioning system inside the tunnel consists of the positioning system and the transmitting system.The positioning system adopts the wireless measuring algorithm,positioning algorithm and inertia navigation algorithm.About the positioning result it is also necessary to make some remedies with the road adhesion algorithm.The transmitting system will adopt the network of wireless data transmission radio modules to send the real-time position of vehicles to the monitoring center with the automatic recognition algorithm in the method of multi intermediate levels.The monitoring center will use the map processing technology to make the actual position and working status of vehicles and equipments visible on the map.Through the verification and trial run in the tunnel road network in some big work sites in the mountain area,it is determined that the accuracy of this positioning system is higher than that of satellite positioning system.As to the working vehicles in the range of 100 square km,the delay of transmission is less than 500 ms.And it meets the requirement of local positioning to the vehicles in the tunnel road network in the mountain area.