Trough waveguides (TWG) have been utilized in a variety of radio frequency
(RF) and other related applications including radar, the treatment of hypothermia and in
the generation of plasmas. Perturbing the guided wave in these structures with blocks,
rods, dielectrics, and other structures can create reconfigurable periodic line sources.
These trough waveguide antennas (TWA) are then capable of providing both fixedfrequency
and frequency-dependent beam steering. This was originally performed using
electro-mechanical “cam-and-gear” mechanisms. Previous work related to the excitation
of TWG and the performance of TWA topologies are limited when compared to more
common antenna designs, yet they possess many desirable features that can be exploited
in a modern system.
This thesis will examines an S-band rectangular-to-trough waveguide transition
and trough guide antenna that has been designed for broadband reconfigurable antenna
applications considering as well the airflow characteristics for sensing applications. The
design, fabrication, and electromagnetic performance (mode conversion, impedance matching, and antenna performance) are discussed, including the use of metallic
cantilever perturbations placed along the troughguide sidewalls that are designed to
provide improved impedance matching when steering the beam from the backward
quadrant through broadside, towards the forward quadrant. Impedance matching
techniques such as use of circular holes at the edge of each actuated cantilever are used
to reduce power reflections and provide a low voltage standing wave ratio (VSWR)
along the S-band. Finite element simulations will provide a demonstration of the airflow
and turbulence characteristics throughout the entire structure, where the metallic
cantilevers are used to manipulate the flow of air, to distribute it across the surfaces of
the structure better and improve its potential for sensing operations.
| Identifer | oai:union.ndltd.org:tamu.edu/oai:repository.tamu.edu:1969.1/ETD-TAMU-2010-12-8908 |
| Date | 2010 December 1900 |
| Creators | Loizou, Loizos |
| Contributors | Robert, Nevels, Huff, Gregory |
| Source Sets | Texas A and M University |
| Language | en_US |
| Detected Language | English |
| Type | thesis, text |
| Format | application/pdf |
Page generated in 0.0019 seconds