Abstract:

Aiming at the problems of large time delay, significant jitter of optical axis and large uncertain field of target position in long-distance inter-satellite laser communication link building with deep space cooperative target, an anti-jitter and high-probability acquisition composite scanning strategy based on two-stage actuator was proposed. The uncertain field of target position was divided into equalsized square subfields. Raster scanning was adopted in subfields, which was realized by the fast steering mirror. The subfields were covered in raster spiral scanning sequence, the transition between which was realized by the servo turntable. Considering the jitter of optical axis, the size of subfields as well as the overlapped parts of scanning spots was optimized through genetic algorithm. The scanning scheme with optimized parameters was obtained and validated by simulation. The simulation results of 1000 times Monte Carlo shooting show that under the consideration of a 3.6mrad uncertain field with the laser beam divergence of 0.1mrad and the standard deviation of optical axis jitter of 5μrad, the acquisition probability is 99.2%, the scanning time of uncertain field is 41.34s, and the average scanning time of the target is 9.62s,based on the optimized scanning scheme.

Key words: deep space exploration, laser communication, optical axis jitter, composite scanning, highprobability acquisition, genetic algorithm