Development of short back-fire antennas and electromagnetic modeling techniques for remote sensing of oil-contaminated sea ice

• Main Author: Mansoori, Amirbahador
• Other Authors: Isleifson, Dustin (Electrical and Computer Engineering), Shafai, Lotfollah (Electrical and Computer Engineering) Ferguson, Philip (Mechanical Engineering)
• Format: Master Thesis
• Language: English
• Published: 2021
• Subjects: Short Back-Fire Antenna; Small Perturbation Model; SPM; NRCS; Normalized Radar Cross-Section; Backscattering; Dielectric Modelling; Dielectric Mixture Model; Sea Ice; Clean Sea Ice; Oil-Contaminated Sea Ice; Antenna Design; Arctic; C-band; Microwave; Remote Sensing; Microwave Remote Sensing; Arctic Remote Sensing; Oil; Regular Ship Diesel; Crude Oil; Marine Ship Diesel; Wideband antenna; Improved Realized Gain antenna; Waveguide fed antenna; Waveguide fed Short Back-Fire antenna; Remote Sensing Antenna; Arctic Technology; Sea ice
• Online Access: http://hdl.handle.net/1993/35704

This thesis presents research into microwave remote sensing technologies for Arctic Science applications. In the first part of my thesis, I created and verified procedures for measuring the dielectric of a small volume of oil with cavity resonator and dielectric probe techniques. I designed and fabricated a cavity resonator and utilized a dielectric probe to demonstrate the technique and to generate new measurement results for three types of oil products. The measurement results are needed in dielectric mixture modelling and simulations of the normalized radar cross-section (NRCS) of oil-contaminated sea ice. I utilized five existing dielectric mixture models and the measured dielectric constants of three types of oil to model both clean and oil-contaminated sea ice. I simulated and compared their NRCS (three different types of contamination with three different amounts). The simulation results showed that I could distinguish between the clean and oil-contaminated sea ice based on the NRCS magnitudes. The simulation results demonstrate that for higher incidence angles, distinguishing clean sea ice from oil-contaminated sea ice with VV polarization is easier than HH polarization. In the second part of my thesis, I designed C-band Short Back-fire antennas that can be used for remote sensing applications. I simulated and characterized six different designs of Short Back-Fire antennas. The first design, SBF-1, is an optimum case of the conventional SBF antenna. In SBF-2, I improved the realized gain and bandwidth of the first one by adding a cylindrical choke to the main reflector. In the third design, I filled the choke with Teflon. In the subsequent designs, I increased the bandwidth and realized gain of SBF-1 and SBF-2 by adding a ring beside the rim and by adding a choke to the rim. To validate the simulations, I fabricated and tested SBF-1 and SBF-2. The measurement results show good agreement between the simulations and the actual measurements. October 2021