Complete Vector Network Analyzer Approach to Ice Penetrating Radar System

Open Access
Author:
Herrold, Brian Alexander
Graduate Program:
Electrical Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
July 12, 2013
Committee Members:
  • Sven G Bilen, Thesis Advisor
Keywords:
  • Ice
  • Radar
  • Vector Network Analyzer
  • VNA
  • Radioglaciology
Abstract:
This thesis explores the design of a complete system for Ice-Penetrating Radar (IPR) measurements of polar-region ice thickness. The goal of the radar system is provide high resolution measurements of of the change in ice thickness between successive measurements at a fixed location on the ice over time. The design requirement for resolution in thickness change is better than ± 1mm. The system designed can make absolute ice thickness to a much less accurate degree than the relative measurements of thickness change. This approach is based on adapting a previously published design for a low-cost Vector Network Analyzer (VNA) to a rugged form factor and optimizing the performance parameters of the instrument to maximize its usefulness for ice-penetrating radar measurements. The radar relies on precise measurement of the magnitude and phase response of the propagation path from transmitting antenna to receiving antenna, through the ice and off the ice bottom, to make the thickness measurements. The phase change of the response of the ice between successive measurements allows the user to determine small thicknesses changes with very high accuracy. The inverse Fourier transform of the magnitude and phase frequency-response of the path provides the time domain approximation of the path response to a very short radar pulse.