Convolutional Neural Networks Approach for Solar Reconstruction in SCAO Configurations

Correcting atmospheric turbulence effects in light with Adaptive Optics is necessary, since it produces aberrations in the wavefront of astronomical objects observed with telescopes from Earth. These corrections are performed classically with reconstruction algorithms; between them, neural networks showed good results. In the context of solar observation, the usage of Adaptive Optics on solar differs from nocturnal operations, bringing up a challenge to correct the image aberrations. In this work, a convolutional approach is given to address this issue, considering SCAO configurations. A reconstruction algorithm is presented, “Shack-Hartmann reconstruction with deep learning on solar–prototype” (proto-HELIOS), to correct on fixed solar images, achieving an average 85.39% of precision in the reconstruction. Additionally, results encourage to continue working with these techniques to achieve a reconstruction technique for all the regions of the sun.

Transmission Characteristics of Adaptive Compensation for Joint Atmospheric Turbulence Effects on the OAM-Based Wireless Communication System

Atmospheric turbulence has an impact on the transmission of electromagnetic vortex waves with an orbital angular momentum (OAM) mode. In this paper, based on the joint atmospheric turbulence model, we examine the influence of atmospheric turbulence on the transmission of electromagnetic vortex waves. First, a mathematical model is established to formulate the transmission characteristics of electromagnetic vortex waves under joint atmospheric turbulence. Subsequently, in order to mitigate the influence of the atmospheric turbulence on the electromagnetic vortex waves, an adaptive compensation on phase is proposed. Finally, we analyzed the transmission performance of an OAM-mode multiplexing system using an adaptive compensation method through the wireless communication channel. By means of numerical simulation, the effect of atmospheric turbulence on the transmission characteristics and mode crosstalk of OAM is analyzed. The simulation results show that electromagnetic vortex waves could perform well on the wireless communication system with a low mode crosstalk, which provides the theoretical support to optimizing the mode division multiplexing technology in a free space communication system.