Comparison of Compact Very High Frequency (VHF) Antennas for Small Airborne Ground Penetrating Radar
Abstract
UHF bands because more penetration can be achieved at low frequencies. Consequently, large antennas are required, which limits their use for small airborne applications. This thesis explores various GPR antenna designs for a bi-static system that are at least operational from 225 MHz to 255 MHz and suitable for small airborne applications. The 3D electromagnetic simulation software Ansys high-frequency structure simulator (HFSS) was used to simulate various sizes of strip dipole, triangular bowtie, half elliptical bowtie, and elliptical bowtie antennas. Several physical models were constructed to validate the return loss simulation results. Additionally, simulation data is included for a wire dipole and a helical antenna. The helical antenna proved to be too large for small airborne application, so focus was placed on the dipole and bowtie designs. The performance of the dipole and bowtie antenna models are compared by size, weight, return loss (ð‘†11), peak gain, and the transmit-to-receive isolation. Out of the fourteen simulated models, twelve meet the bandwidth requirement with an average weight of 0.23 lbs. It is found that the strip dipole exhibited wider bandwidth characteristics than the triangular, elliptical, and half elliptical bowtie models, while maintaining similar weight and size. The smallest strip dipole model is 50 mm x 528 mm x 1 mm, weighs 0.17 lbs, and is operational from 225 MHz to 283 MHz. Two strip dipole test antennas were fabricated and tested. Test results confirm the simulation predictions.
Degree
MS
College and Department
Ira A. Fulton College of Engineering; Electrical and Computer Engineering
Rights
https://lib.byu.edu/about/copyright/
BYU ScholarsArchive Citation
Livingston, Tayler Austen, "Comparison of Compact Very High Frequency (VHF) Antennas for Small Airborne Ground Penetrating Radar" (2023). Theses and Dissertations. 9998.
https://scholarsarchive.byu.edu/etd/9998
Date Submitted
2023-07-25
Document Type
Thesis
Handle
http://hdl.lib.byu.edu/1877/etd12836
Keywords
triangular bowtie antenna, half elliptical bowtie antenna, elliptical bowtie antenna, strip dipole antenna, helical antenna, VHF, compact, ground penetrating radar (GPR)
Language
english