Date of Award


Document Type


Degree Name

Master of Science in Aeronautical Engineering


Department of Aeronautics and Astronautics

First Advisor

Richard G. Cobb, PhD.


The proliferation of unmanned aerial vehicles (UAVs) in both military and civilian settings has prompted great interest in finding new and innovative ways to utilize these tools. One such application is to locate ground-based radio emitters from a UAV platform. The goal of this research is to study the feasibility of a low-cost (on the order of $1000) UAV geolocation platform. To accomplish this goal, a series of both real-world flight testing and computer simulated scenarios were conducted. Simulations for different sensor uncertainties and approach path scenarios such as loiter and button hook patterns were investigated. Results showed that a high uncertainty sensor of ±10 degrees was able to reliably geolocate the target provided it could fly sufficiently close to the emitter location. For the physical testing, a commercial-off-the-shelf Doppler direction finding unit was chosen as the method of performing the geolocation. Ground testing proved promising, locating the emitter to within 20 meters. However, flight testing showed poor results and was unable to locate the target. Areas of future work that could improve upon these results include investigating how altitude and antenna orientation variations caused by the movement of the aircraft affect the performance of the direction finding unit.

AFIT Designator


DTIC Accession Number