Research And Implementation Of Visible Light Communication Equipped Vehicles

In recent years,research on Internet of Vehicles(IoV)has received great attention from academia and industry.The Io V was designed primarily to transmit road navigation information and traffic safety information,and to improve transportation efficiency.However,with the development of computer technology and people's need for high-quality travel,the Io V has also taken on the task of information transmission in the fields of entertainment and video.In the traditional Io V communication system,the information exchange between the car and X(vehicle,road and people)is based on radio communication,but with the increasing number of vehicles and the emergence of various wireless access devices,limitted radio spectrum resources are unable to meet the growing demand for communications.At present,with the development of Light-Emitting Diode(LED)technology and its wide use in traffic lights and traffic lights,LED-based visible light communication technology is regarded as a kind of communication technology in Io V because of its safety,no electromagnetic interference and no need for spectrum application.Based on this,this paper designs a vehicle-mounted visible light communication system to realize the information interaction between the vehicle and the outside world.In this paper,firstly,the characteristics of the light source at the transmitter and the principle of its illuminating in the vehicle-mounted visible light communication system are analyzed.Meanwhile,the characteristics and adaptation scenarios between different photosensitive devices at the receiver are compared and analyzed.Then,the mathematical model of the channel DC gain and Vehicle-to-Vehicle(V2V)communication are established.Secondly,based on the previous research and analysis,the software and hardware structure of the vehicle-mounted visible light communication system is designed.The hardware circuit of the system includes the transmitter and the receiver: the hardware circuit of the transmitter mainly includes an LED light source and an LED driving circuit;and the hardware circuit of the receiver mainly comprises a PIN photodiode,a preamplifier circuit,a signal main amplifier circuit,a low pass filtering circuit and a comparator circuit.The design of the principle and the selection of the device are described in detail.The software part of the system contains the preparation of the web interface and the server-side logic function.The web interface presents the user with various options for different functions.The background server can control the hardware circuit to respond accordingly according to the function selected by the user.Finally,the vehicle-mounted visible light communication system designed in this paper was test.The two smart cars equipped with the system were driven in a straight line,and the text chat function and video transmission function of the system were tested during the driving process.After many tests,the test results shows that the system has achieved the pre-set goal: the video can be transmitted normally when the communication distance between the front and rear cars is within 30 cm,and the text chat function can be used normally when the communication distance between the front and rear cars is less than 50 cm.