| As people’s demand for real-time high-speed communication technology becomes more urgent and the microwave communication rate is approaching the limit,the emerging visible light communication technology has become a research hotspot in the world in the world due to its high bandwidth and high-speed advantages.Among them,laser wireless communication technology with higher modulation bandwidth,high efficiency and beam convergence is the forefront of industry research.This thesis designs an end-to-end laser wireless communication platform,and finally realizes the function of real-time transmission of information flow.The research work is mainly divided into two aspects:hardware platform and software system.The hardware platform of the laser wireless communication system includes a transmitter,a receiver,and a temperature control circuit for stabilizing the temperature of the laser diode.Combined with laser diodes of three colors of red,green and blue,the key issues in the design process of the laser wireless communication platform are fully considered,and it is expected to achieve a deep coupling of communication and lighting.The temperature control circuit uses an analog PID circuit to control the thermal circuit of the semiconductor refrigeration chip,thereby maintaining the laser diode temperature constant and avoiding the influence of temperature drift on communication quality.Combined with the actual application of the laser wireless communication platform,a reasonable communication protocol is designed.The software design of the laser communication platform is further implemented under the Linux platform,including functional modules such as data transmission and bit error rate detection.For the Raspberry Pi software operating platform,the code is deeply streamlined and the operating logic is optimized to save the consumption of hardware resources.Finally,the system and performance testing of the laser wireless communication platform were performed.The transceiver system and the temperature control circuit met the requirements of the index.The experimental platform was set up to test the frequency response of the channel and the key parameters of the digital link.Calculate the bit error rate and complete the information stream transmission. |
