针对车联网中的通信需求, 本文提出了一种即插即用的可见光车灯信号发送控制装置。装置利用车灯低压直流供电线路进行信号传输, 并通过车灯发送可见光通信信号。装置前级将接收的输入信号, 由高速开关电路控制线路的供电通断, 从而将通信信号传导至后级并由后级控制 LED车灯发送可见光信号。通过推导和实验选用电容作为线路储能器件, 并采用 2FSK调制和 Modbus协议建立前后级间通信。实验证明装置可以利用线路实现最快不低于 4 Mb/s的信号传输, 并通过可见光车灯控制地锁的实验模型, 进一步验证了该装置接收信号并通过低压直流供电线路控制车灯发送可见光信号的功能。本设计为利用直流供电线路传输信息并点亮的 LED灯实现可见光通信, 提供了参考设计模型。

To address the needs of the Internet of Vehicles, a plug and play visible light signal transmis. sion control device was designed for a vehicle lamp. In this device, the signal was first transmitted to a light-emitting diode(LED)driver via the DC power line and output as flashes of the vehicle LED lamp. The device was composed of a front-end circuit and a back-end circuit. The power switching was con. trolled by a high-speed on-off circuit in the front-end circuit based on the received input signal. The signal in the DC power line was then transmitted to the back-end circuit. Based on the signal, the VLC signal was sent by driving the flashing LED lamp. A capacitor was selected as the energy storage module after charge – discharge analysis. The communication between the front-end and back-end circuitry was achieved with 2-frequency shift keying(FSK)modulation and Modbus protocol. The device tests showed that the signal could be transmitted over the DC power line at minimum speeds of 4 Mb/s. The design and testing of the VLC parking lock control module also proved the feasibility of the communication and control functions. Thus, the proposed device could be a reference design for DC power line communication for an LED VLC system.