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    Control of Daptive Optics Systems

    , M.Sc. Thesis Sharif University of Technology Beigrezaei, Ali (Author) ; Jalali, Mir Abbas (Supervisor)
    Abstract
    Light has planar wavefront as it propagates in vacuum but in the atmosphere, because it passes through layers with different refractive indices, this planar wavefront is lost. Consequently light is distorted when it enters optical instruments. This issue results in images with low resolution. Adaptive optics is a method used for compensation of these distortions in order to obtain higher resolution. So far adaptive optics systems are successfully used in ground based telescopes and an increasing effort on developing and improving these systems is made. Most of these studies are performed from the optics point of view, but techniques from control theory can be applied to adaptive optics... 

    A Novel Model for Three-Dimensional Imaging Using Interferometric ISAR in Curved Target Flight Paths

    , Ph.D. Dissertation Sharif University of Technology Nasirian, Mahdi (Author) ; Bastani, Mohammad Hasan (Supervisor)
    Abstract
    A Synthetic Aperture Radar (SAR) is a system which collects the received signal from a ground target area along linear motion of a flying vehicle carrying it, in order to provide a very high resolution 2D image of it. In Inverse SAR (ISAR), the radar is fixed on the ground and the data collection is performed along the linear motion of the aerial target. Using a second receiver antenna close to the main transceiver antenna of ISAR, it is possible to make a three-dimensional (3D) image of the target, or equivalently find the 3D coordinates of the target scattering points. Such system is called bistatic, monopulse or interferometric ISAR (InISAR). In the conventional model of ISAR, the flying...