Design And Implementation Of Remote Vehicle Diagnostic System Based On TD-LTE Technology

In recent years,the demand for cars has been increasing.With the rapid development of science and technology,vehicle electronic control system has been highly electronic and complex,the vehicle failure are more and more complex,fault components are difficult to determine and fault type is difficult to analyze.This paper have designed and implemented a vehicle remote fault diagnosis system based on TD-LTE technology,it solves the problems of vehicle remote fault diagnosis system based on Bluetooth,WIFI,3G and so on,it has the low cost,high speed,without geographical restrictions,and it can receive real-time remote fault information.Combining the characteristics of OBD-II system and the advantages of TD-LTE technology,this paper puts forward the design scheme of vehicle remote fault diagnosis system based on TD-LTE technology.Firstly,the hardware platform of the whole system is designed according to the requirements of the project,the OBD-II module uses DCAN103 C as fault diagnosis chip to interact with vehicle interaction.The main controller is connected to the IO through,the control line,to achieve the sleeping and waking up,and data transmission of TD-LTE module.At the same time,the ESP8266 WIFI module is designed to access wireless hotspots easily.When the plethora of data is transmitted,it can effectively save TD-LTE traffic.There is a HMI to be the human-computer interaction which can display the vehicle running parameters and fault alarm information on time.Secondly,in the software design,DCAN103 C acquire and analyze the OBD standard data stream according to the link layer protocol in the diagnostic protocol,and extract the OBD standard fault code for fault analysis.TD-LTE network conduct transparent two-way transmission between devices by the TCP data link,and designed a TD-LTE off-network redial for vehicles traveling in the tunnel signal blind.Then the My SQL database is established to manage the basic information of the vehicle,including the vehicle running status information and the vehicle fault information,the Tomcat based J2 EE is used to build the fault diagnosis center server which can accomplish the reception and analysis of upload data.Finally,theAPI software platform is used to monitor the engine speed,coolant temperature,vehicle speed and other parameters.After debugging the system,the rate of vehicle terminal remote reading the fault transmission stabilizes at 30 Mbps,the transmission delay is about 0.4S,up to 45 faults can be diagnosed,the system can effectively improve the coverage rate of signal in signal blind area such as tunnel,can start the double insurance measures of LTE-WIFI flow,the system has a certain practical value for safety stable operation of automobile.