Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 4 of 4
Full-Text Articles in Engineering
The Use Of Scattering Cancellation To Cloak And Decouple Slot Antennas And Antenna Arrays, Daniel Ferro
The Use Of Scattering Cancellation To Cloak And Decouple Slot Antennas And Antenna Arrays, Daniel Ferro
Honors Theses
The concept of cloaking has been prevalent in emerging research, being able to hide oneself completely from outside observers would be a huge benefit for covert surveillance and other fields. This idea has expanded past optical invisibility into the field of electromagnetic invisibility. To accomplish this form of cloaking, a non-natural material, called metamaterials, must be used. Furthermore, metamaterials can be used in a variety of different techniques including transformation-based cloaking, transmission line cloaking, and scattering cancellation cloaking. One application of cloaking is to use scattering cancellation to decouple two antennas that are placed too closely together such as in …
Reduction Of Mutual Coupling In Antenna Technology Using Elliptically Shaped Metasurfaces, Gabriel Moreno
Reduction Of Mutual Coupling In Antenna Technology Using Elliptically Shaped Metasurfaces, Gabriel Moreno
Electronic Theses and Dissertations
This thesis is devoted to the use of metasurfaces for the goals of the reduction of mutual coupling between closely spaced antennas and the increase of antenna bandwidth. This is done first using a graphene monolayer as a cloak to decrease mutual coupling and restore radiation patterns for closely spaced antennas at THz frequencies. The introduction of the graphene monolayer was also extensively studied in regards to the effect on the radiation properties of the antennas. The use of metasurfaces also has other applications, in particular with the bandwidth of antennas, where an anisotropic metasurface can be used to drastically …
Reconfigurable Microstrip Antennas With Tunable Radiation Pattern Characteristics, Ahmed Khidre
Reconfigurable Microstrip Antennas With Tunable Radiation Pattern Characteristics, Ahmed Khidre
Electronic Theses and Dissertations
Reconfigurable beam antenna systems are capable of changing their radiation characteristics in real time, such as beam direction, beam shape, beamwidth, etc. Such antenna system is desired for various wireless applications because of many reasons among them; it helps to enhance signal strength received from an intended target, mitigates interference, and accommodates sudden changes in traffic demand of wireless networks. It might also help to reduce the deployment cost of wireless networks infrastructures. In this dissertation, designs for reconfigurable beam microstrip antennas with tunable radiation characteristics have been proposed. The method to achieve these designs is the reconfigurable parasitic element …
Characteristics Of Different Focusing Antennas In The Near Field Region, Shaya Karimkashi
Characteristics Of Different Focusing Antennas In The Near Field Region, Shaya Karimkashi
Electronic Theses and Dissertations
Focusing antennas are of interest in many application including microwave wireless power transmission, remote (non-contact) sensing, and medical applications. Different kinds of antennas such as array antennas, reflector antennas and Fresnel zone plate (FZP) antennas have been used for these applications. Here, first, a new scheme in designing focused array antennas with desired sidelobe levels (SLLs) in the near field region is presented. The performance of the large focused array antennas is predicted based on the knowledge of the mutual admittances of a smaller array. The effects of various focal distances on the near field pattern of these antennas are …