Research of the PPM Modulation Technology in Space Communication

Fiber laser has the characteristics of high peak power, short Pulse-width and good beam quality and play a larger role in the field of laser communication, laser cutting, and medical instruments. This paper first study on theoretical research of pulse single pulse energy, peak power, pulse width of the Q-switched fiber laser, and characteristic curve between the pulse peak power of Q-switched fiber laser. The laser shock parameters were obtained through simulation, combined with L-PPM signal model analysis. The best selection of L-PPM digits in the repetition frequency of the laser is under certain conditions, through the research on some important parameters such as slot width of PPM signal, length of transmission slots, and length of guard slots. Arrival at a conclusion of the modulation characteristics of PPM based on fiber laser, through theoretical analysis and experimental simulation,proved that under the condition of the lower repetition frequency PPM can provide a higher modulation rate.