abstract: Artificial magnetic conductor (AMC) surfaces have the unique electromagnetic property that the phase of the reflected fields imitate those of perfect magnetic conductors (PMCs). When a perfect electric conductor (PEC) and an AMC surface are placed on the same plane and illuminated by a plane wave, destructive interference occurs between the fields (due to 180 degrees phase difference between the reflected fields of each surface).
In this dissertation, a design procedure is introduced where a refined algorithm is developed and employed on single-band AMCs leading to a 10-dB RCS-reduction bandwidth of 80%. The AMC circuit model is judiciously utilized to reduce the substrate thickness while simultaneously increasing the bandwidth of the AMC surfaces. Furthermore, dual-band AMC surfaces are synthesized and utilized in combination with single-band AMC surfaces to extend the 10-dB RCS-reduction bandwidth from 80% to about 99%. Employing the proposed design procedure, a 99% bandwidth of 10-dB RCS-reduction bandwidth is achieved while reducing the thickness of the substrate by 20%.
The second topic of this dissertation aims at analytically modeling the scattering of planar checkerboard surfaces. The high-frequency asymptotic method, Physical Optics (PO), is utilized to analyze the scattering characteristics of complex structures since the PO is computationally efficient and provides intuitive physical insight. Closed-form formulations developed using PO are used to predict the scattering patterns of checkerboard planar surfaces. The PO-based data compare well, along and near specular directions, with simulations by the full-wave Finite Element Method (FEM).
Finally, a Van Atta retrodirective reflector with low backscattering is designed and developed using a microstrip antenna array. Conventional retrodirective reflectors are sensitive to interference by the fields scattered by the antenna structure. By using a virtual feeding network, structural mode scattering is identified and canceled using AMC technology. / Dissertation/Thesis / Doctoral Dissertation Electrical Engineering 2020
| Identifer | oai:union.ndltd.org:asu.edu/item:62950 |
| Date | January 2020 |
| Contributors | ALYAHYA, MESHAAL (Author), Balanis, Constantine A. (Advisor), Palais, Joseph C. (Committee member), Aberle, James T. (Committee member), Trichopoulos, Georgios C. (Committee member), Arizona State University (Publisher) |
| Source Sets | Arizona State University |
| Language | English |
| Detected Language | English |
| Type | Doctoral Dissertation |
| Format | 107 pages |
| Rights | http://rightsstatements.org/vocab/InC/1.0/ |
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