Design And Research Of GPS, 3G Vehicle Location And In-car Video Surveillance System

With the rapid development of transportation industry in our country,it is imperative for transport vehicles to have effective monitoring and management, also pay more and more attention to the safety of personnel and vehicles.Therefore,it is very necessary to design a based on GPS,3G vehicle positioning and vehicle video monitor system, the principle of the system implementation is that the vehicle terminal’s GPS positioning information and the acquisition of video information is transmitted to the monitoring center server through3G wireless networks,the monitoring center clients can view real-time vehicle location on an electronic map, as well as view the historical trajectory of the vehicle,also can be real-time video monitoring of vehicles.In this paper, discussing about the system of GPS positioning, Baidu Map, communication platform, video compression and transmission, etc.Firstly,in this paper, has made the detailed introduction to involved in vehicle positioning and vehicle video monitor of GPS positioning technology,3G wireless network technology, video compression coding technology, streaming media server, etc.Then respectively introduce the design principle of vehicle positioning and vehicle video monitor, by comparing the WCDMA standard of3G wireless network as the communications platform, Illustrating the entire vehicle monitoring system is made up of vehicle positioning subsystem and vehicle video monitoring subsystem.GPS,3G vehicle positioning subsystem adopts the advanced GPS technology, the popularity of3G wireless network, free and open API of Baidu Map and data processing technology.Using the GPS car terminal set time intervals for the vehicle’s location information, the monitoring center and vehicle-mounted terminal through a3G wireless network two-way,real-time data transmission,and the monitoring center to parsed GPS latitude and longitude coordinates through the obtaining positioning information,combined with Baidu Map API, you can real-time location of vehicles, through the historical location data stored in the database, you can view the historical trajectory of the vehicle.It’s realization of vehicle real-time position and historical track playback demand. Vehicle-mounted video monitoring subsystems that considering the3G wireless network traffic and bandwidth problems, using the latest video compression coding standard—H.264,This will not only reduce the3G network data traffic, but also improves the speed of transmission of the video stream.In order to improve the encoding rate of the video stream, we have chosen the x264as encoder, the coding efficiency and quality has been well represented.In the sender of video streaming transmission to realize the QoS control mechanism, in the network congestion, the design is based on image quality and frame rate control method of adaptive adjustment, can solve the network congestion phenomenon,and according to packet losing problem, design a ring buffer is used to store the packets sent, is used to implement feedback and retransmission function, to solve the problem of high packet losing in the network transmission process. It’s realization of vehicle remote video real-time monitoring demand.