Research On Beacon Light With 3W/800nm Band Laser Drive Technology

With the continuous development of space optical communication technology,beacon light plays an increasingly important role in the spatial optical communication system.The beacon light source plays a decisive role in the entire space optical communication system.To obtain the beacon light that meets the requirements of space optical communication,a reasonable drive circuit must be designed for the beacon light semiconductor laser to ensure that the laser outputs a stable optical power.The main work of this dissertation is to design the driving circuit for 3W/800 nm beacon semiconductor laser in space optical communication system.The main design includes: temperature control circuit,power control circuit and protection circuit.The entire driver design is controlled by the microcontroller.At the beginning of the thesis,we mainly introduced spatial optical communication and semiconductor lasers.The related characteristics of semiconductor lasers mainly include P-I characteristics,I-V characteristics,and temperature characteristics.The influence of temperature on the semiconductor laser is summarized.the temperature mainly affects the laser output power,threshold current,and wavelength.Then the paper introduces the design of semiconductor laser driver circuit.Mainly include temperature,power control and protection circuits.Temperature control circuit through the digital PID algorithm,using SCM software programming to achieve temperature compensation,so that the temperature tends to be constant.The power control circuit realizes the stability of the constant current source output through negative feedback technology,using digital control technology,the digital potentiometer is controlled by the single chip to adjust the output current of the constant current source so as to realize the control of the output power of the semiconductor laser.Finally,the designed driving circuit is verified through experiments,and the experimental conclusion is analyzed,the designed laser driving circuit can enable the beacon light emitted by the beacon laser in the space optical communication system to complete the functions of capturing,tracking and positioning,and meet the index requirements specified in the spatial optical communication system.