The Research Of Optical Adaptive Operating System Based On The Intensity-investigation In Intersatellite Optical Communications

Intersatellite optical communications, known with high communication speed, large capacity, strong anti-interception and anti-interference capability, small and lightweight, also with lower power consumption, are widely used in intersatellite communication and local broadband access technology, as well as in the field of military anti-jamming communication and also have a great development potential. Optical adaptive technique is brought into the communication system to solve the problem of atmospheric turbulence affecting the communication quality.The conventional optical adaptive technique is effective in solving the distortion of uplink and downlink. However, when used in horizontal-link, the optical adaptive calculations of compensation effect weakened much due to the effect of atmospheric turbulence.In this article, CCD was adopted as the detector , the phase retrieval GS algorithm as the control algorithm, and Liquid Crystal Spatial Light Modulator (LC-SLM) as the calibrator. Thus, we were able to establish optical adaptive system based on the intensity-investigation. LC-SLM has a better spatial resolution and reliability, smaller size, lower cost and consumption and is easier to control, when compared with the commonly used deformable mirror. Furthermore, the system is well applied to atmosphere optical communications with severe scintillation, because the system can directly transform the detected light distribution into the phase distribution through the iterative phase retrieval algorithm, without wavefront detection.We developed a control system using the LabVIEW to realize the well control of the new system. We completed the new system after master the LabVIEW.For the software part, the system was divided into four parts according to their various functions, which were respectively acquisition image module, operation of the module, output precision and the control module of the algorithm. Besides, CCD was controlled by the acquisition image module to capture images. The captured images were transformed into two-dimensional matrix and then delivered to the module of GS algorithm. The control module of the algorithm had control over the times of GS algorithm.The controlled quantity of the liquid crystal spatial light modulator was calculated and was put out by the output module.Finally, we tested the characteristics of phase modulation of the liquid crystal spatial light modulator to obtain the accuracy control. We also studied the ability of the system to correct the simple distortion and complex distortion. For the former, we tested the condition of the same iterated initial values and different iterations, and also the condition of the same iterations and different iterated initial values.In this article, we proposed optical adaptive system based on the intensity-investigation, designed and completed the new system by LabVIEW. This is a reference value of the application of the system in the optical communications.