Optimization of Focusing by Strip and Pixel Arrays

Burke, G J ; White, D A ; Thompson, C A

Lawrence Livermore National Laboratory

关键词: Dielectric Materials;    36 Materials Science;    Simulation;    42 Engineering;    Annealing;   

DOI  :  10.2172/891729
RP-ID  :  UCRL-TR-213455
RP-ID  :  W-7405-ENG-48
RP-ID  :  891729

美国|英语

来源: UNT Digital Library

【 摘 要 】

Professor Kevin Webb and students at Purdue University have demonstrated the design of conducting strip and pixel arrays for focusing electromagnetic waves [1, 2]. Their key point was to design structures to focus waves in the near field using full wave modeling and optimization methods for design. Their designs included arrays of conducting strips optimized with a downhill search algorithm and arrays of conducting and dielectric pixels optimized with the iterative direct binary search method. They used a finite element code for modeling. This report documents our attempts to duplicate and verify their results. We have modeled 2D conducting strips and both conducting and dielectric pixel arrays with moment method and FDTD codes to compare with Webb's results. New designs for strip arrays were developed with optimization by the downhill simplex method with simulated annealing. Strip arrays were optimized to focus an incident plane wave at a point or at two separated points and to switch between focusing points with a change in frequency. We also tried putting a line current source at the focus point for the plane wave to see how it would work as a directive antenna. We have not tried optimizing the conducting or dielectric pixel arrays, but modeled the structures designed by Webb with the moment method and FDTD to compare with the Purdue results.