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Showing 1 to 20 of 37 for “"physical optics"”.

  1. Ray-based Physical Optics for the Design of Astronomical Observatories

    Ashcraft, Jaren N.The University of Arizona.2024

    … diffraction-limited optical systems an accurate physical optics model is necessary to properly evaluate instrument performance. Industry-standard commercial optical design packages as well as existing open-source physical optics tools achieve this by the propagation of a complex-valued scalar …

    arizona-thes Repository record

  2. Graphical user interface for a physical optics radar cross section prediction code

    Garrido, Elmo E.Monterey, California. Naval Postgraduate School2000

    This implementation of the physical optics approximation method for predicting the radar cross section (RCS) of complex objects utilizes the scientific computational features of MATLAB and its Graphical User Interface (Gui) functions to provide an error-free encoding of input parameters and …

    nps Repository record

  3. Acceleration of asymptotic computational electromagnetics physical optics — shooting and bouncing ray (PO-SBR) method using CUDA

    Meng, Huan-TingUniversity of Illinois at Urbana-Champaign2011

    … objective of this research is to accelerate the Physical Optics - Shooting and Bouncing Ray (PO-SBR), an asymptotic computational electromagnetics (CEM) method, on the recently emerged general purpose graphics processing unit (GPGPU) using NVIDIA’s CUDA environment. In modern engineering, …

    uiuc Repository record

  4. A Study of Electromagnetic Scattering of Communication Signals by Randomly Rough Surfaces

    Stockland, Robert ThomasVirginia Tech2022

    … it propagates. This research also modifies the Physical Optics (PO) algorithm utilizing Fourier decomposition to compare the Extended MOMI algorithm to. Both algorithms are applied to propagation scenarios utilizing frequencies in the 1-GHz and 5-GHz bands against a series of signal bandwidths …

    vt Repository record

  5. Multiple feed reflector antenna analysis

    Stewart, Scot HowardVirginia Polytechnic Institute and State University1986

    … by a feed array is developed. Geometrical optics is used to determine the incident field via a coordinate transformation approach. The incident field from each element is superimposed to form the total field used in finding the surface currents of the physical optics radiation integral. The …

    vt Repository record

  6. Modelling of Electromagnetic Scattering at Infrared Wavelengths by Pristine Ice Crystals

    Shaker, JawadUniversity of Essex2019

    … In this work, a new approach basedon physical optics is presented in which the scattering by smooth prismatic dielectric ice crystalswhich are electrically large is evaluated. In this method, the total scattered amplitude in anydirection can be evaluated by application of the reaction …

    essex Repository record

  7. Design and Analysis of Quasioptical Components for use in Astronomical Telescopes

    Sheridan, Rory EoinNational University of Ireland Maynooth2018

    … the use of Gaussian beam modes (GBM) and physical optics (PO) to design and analyse astronomical telescope systems operating at millimetre and submillimetre wavelengths. The techniques are applied to a proposed re-design of the 3 mm channel of the 20 m Onsala Space Observatory telescope. …

    maynooth Repository record

  8. Effects of random surface errors on the performance of paraboloidal reflectors

    Boonsalee, Siwaphong, 1974-Massachusetts Institute of Technology2001

    … plane. They are compared with results based on physical optics and the antenna tolerance theory.

    mit Repository record

  9. Analysis and Optimization of Reflector Antenna Systems (Pattern Calculation, Optimum Directivity, Sidelobe Reduction)

    Lam, Peter Tak ChunUniversity of Illinois at Urbana-Champaign2014

    … orientation. The methods of analysis used are physical optics (PO) and the application of the Fast Fourier Transform (FFT) to the aperture fields obtained using geometrical optics (GO), geometrical theory of diffraction (GTD) and a brute-force FFT. Key features of the present work are (i) the …

    uiuc Repository record

  10. Quasi-Optical Design and Analysis of Bolometric Interferometers for Cosmic Microwave Background Experiments

    Curran, Gareth S.National University of Ireland Maynooth2010

    … design of QUBIC is also analysed, including a physical optics analysis of lenses, although not in the same detail as MBI-4. A number of techniques are used in this analysis, including Gaussian beam modes and physical optics, to allow for a complete model of the optical systems to be obtained. …

    maynooth Repository record

  11. ΣΚΕΔΑΣΗ ΗΛΕΚΤΡΟΜΑΓΝΗΤΙΚΟΥ ΚΥΜΑΤΟΣ ΑΠΟ ΑΓΩΓΙΜΗ ΕΠΙΦΑΝΕΙΑ ΣΤΟΧΑΣΤΙΚΑ ΑΝΩΜΑΛΗ ΚΑΙ ΧΡΟΝΙΚΑ ΜΕΤΑΒΑΛΛΟΜΕΝΗ

    Χρυσουλίδης, Δημήτριος, Chrissoulidis, DimitriosAristotle University Of Thessaloniki (AUTH)1983

    … USING THE BOUNDARY PERTURBATION APPROACH OR THE PHYSICAL OPTICS INTEGRAL ALONG WITH THE QUASI-STATIONARY APPROXIMATION, IT IS PROVEN THAT THE INCOHERENT POWER SCATTERED FROM A NONSTATIONARY AND HOMOGENEOUS SURFACE VARIES WITH TIME THROUGH THE TIME-VARYING SURFACE STATISTICS. ON THE OTHER HAND THE …

    greece Repository record

  12. Numerical modeling and ray tracing of SPatIal Frequency modulation for Imaging

    Skogen, Brandon J.Colorado School of Mines. Arthur Lakes Library2018

    This thesis presents the first full geometric and physical optics characterization of aberrations and the performance of a simple system that implements SPatIal Frequency modulation for Imaging (SPIFI). SPIFI utilizes a chirped frequency mask that modulates the intensity of light along a single axis …

    colo-mines Repository record

  13. A measurement of the extent of the color-sensitive areas of the retina and of the wavelengths of light stimulating the respective receptor mechanisms

    Rinde, Charles A.2018

    … consistent. Prof. R. S. Minor, in his course on physical optics, discussed color vision from the physicist’s standpoint, making use of the Young-Helmholtz theory; while Prof. G. M. Stratton gave the psychological treatment, based upon the Ladd-Franklin theory, as a part of his general psychology. …

    u-pacific Repository record

  14. Creation and Experimental Validation of a Numerical Model of a Michelson Interferometer

    Stancil, Maurice MarcusVirginia Tech2017

    … and skills of the investigator in the realm of physical optics, and by the need to make a useful analytical tool available to other investigators in the larger effort.

    vt Repository record

  15. High-frequency electromagnetic wave scattering from rough surfaces

    Marzougui, AdelUniversity of Illinois at Urbana-Champaign2011

    … is based on a combination of the geometric optics (GO) theory and the physical optics (PO) theory. The SBR method improves on the Kirchhoff approximation by considering the mutual interactions between the irregularities of the surface (i.e., shadowing and multiple scattering are accounted …

    uiuc Repository record

  16. Beam scanning offset Cassegrain reflector antennas by subreflector movement

    LaPean, James WilliamVirginia Tech1993

    … test case is beam scanned using two geometrical optics methods of determining the optimum subreflector position for the desired scanned beam direction. Physical optics far-field results are given for the beam scanned systems. The test case system is found to be capable of beam scanning over a …

    vt Repository record

  17. Physically Realistic Rendering of Complex Materials Using Wave optics

    Xia, MengqiCornell University2022

    … material models due to the built-in ray optics assumption. For example, rendered backlit hair is much dimmer than it is in real life and colorful glints are missing in dark animal fur. To improve the realism of visual effects and VR/AR applications, advanced material models that consider …

    cornell Repository record

  18. Improving Electromagnetic Bias Estimates

    Millet, Floyd W.2004

    … Due to incomplete understanding of the physical processes which cause the bias, current operational models are based on empirical relationships between the bias wind speed and significant wave height. These models reduce RMS estimation errors of the EM bias to approximately 4 cm.</p> …

    byu Repository record

  19. Development of a scanning system for use in the Terahertz region of the Electromagnetic Spectrum

    McLaughlin, BrianNational University of Ireland Maynooth2012

    … Gaussian Beam Mode Analysis (GBMA) and Physical Optics. The effectiveness of these techniques are highlighted by using each method to model elementary optical systems. The techniques are then used to computationally model the optical system used for the prototype developed and results …

    maynooth Repository record

  20. Azimuth Modulation of the Radar Backscatter at Near-Normal Incidence

    Greenwood, Andrew D.2003

    … on the surface conditions. In this thesis, a physical optics approach is used with a two-dimensional surface model to derive the electromagnetic backscatter from the ocean surface. If the waves on the ocean surface are directed, azimuth modulation is predicted at near-normal incidence angles. …

    byu Repository record

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