Research On Wavefront Processing And Control Technology Based On Heterogeneous Computing Platform

Adaptive optics plays a salient role in the large-aperture ground-based telescope,laser transmission,laser communication,and laser beam quality control.In the practical application of beam cleanup engineering,the adaptive optics system is devoted to perform real-time wavefront correction of the laser beam,which can achieve the optimization of beam quality and the improvement of optical axis stability.As the“brain” of the adaptive optics system,the stability and high efficiency of the wavefront processing system is an important part to ensure the beam purification performance.On the one hand,the wavefront processing platform needs to be as small as possible,with low power consumption and high integration based on satisfying high real-time performance.On the other hand,in addition to the influence of the optical axis disturbance caused by the atmospheric turbulence and other transmission media,the beam on the mobile platform will also face the low-frequency and high-frequency jitter of the mechanical vibration input of the platform and the system,which requires a constructive wavefront-control algorithm to effectively suppress the low and high frequency beam jitter simultaneously.Therefore,this thesis regarding the wavefront processing and control based on heterogeneous computing platform Therefore,this paper needs to focus on both low-frequency and high-frequency jitter suppression from the wavefront processing platform and wavefront control technology.Firstly,the workflow and real-time requirement of wavefront processor in adaptive optics system are clarified.The advantages of the wavefront processing platform based on Zynq heterogeneous computing platform for image data processing and parallel computing in adaptive optical systems are analyzed.The co-design method and the overall scheme design based on the heterogeneous computing platform are introduced,and the wavefront slope calculation,wavefront restoration and wavefront control modules of the adaptive optical system are completed.Finally,the operation of wavefront processing platform based on heterogeneous computing platform is realized.Then,a hybrid control technique based on LQG + PI is proposed to suppress the beam jitter.According to the source of the beam jitter,a second-order autoregressive model with practical physical meaning is established,and its Spectral density is analyzed.Subsequently,the model parameters are identified with the extraction of the frequency of the signal.A hybrid control system for suppressing beam jitter is built and the response matrix linear migration problem is optimized.The jitter suppression performance of the proposed hybrid control strategy is testified by numerical simulation.Finally,an adaptive optics experiment platform based on the heterogeneous computing platform proposed in this paper is set up to verify the LQG + PI control for the suppression of the jitter signals with different single frequency components and composite frequency components.The results demonstrate that the hybrid control strategy presented in this paper has better jitter suppression performance for both lowfrequency disturbances and high-frequency jitter than existing control methods.