Date of Award

Spring 1-2012

Document Type


Degree Name

Master of Science (MS)

First Advisor

Timothy X. Brown

Second Advisor

Douglas C. Sicker

Third Advisor

Harvey M. Gates


There is increasing interest in Unmanned Aircraft Systems (UAS) as they can be used for various applications, such as border patrol and real estate photography. However, currently the widespread integration of UAS into the U.S. National Airspace System (NAS) is prevented by several problems. One such problem relates to the radio spectrum for Command and Control (C2), which is the communication link between the Ground Control Station and the Unmanned Aircraft for controlling the aircraft remotely. There are two aspects of the UAS spectrum problem: spectrum scarcity and static spectrum management. First, there is currently no dedicated spectrum for civilian UAS C2. Second, the static approach to spectrum management, where spectrum is assigned for long periods of time over large regions, makes spectrum underutilized for most of the times although it is fully allocated.

The UAS spectrum problem could be solved by the use of Policy-based Cognitive Radios. Policy-based cognitive radios could introduce innovative ways to acquire spectrum: using frequency bands otherwise neglected by UAS, spectrum leasing, and utilizing underused spectrum. Policy-based radios will also be an automatic tool to manage spectrum.

This thesis deals with the conceptual design of a policy-based cognitive radio system that could support UAS C2. The aim of this thesis is to explore the use of cognitive radios as a tool for spectrum management for UAS C2. We design a policy-based cognitive radio system to flexibly manage spectrum for UAS C2 while satisfying stakeholder requirements to support the operations of UAS. We identify requirements from the stakeholders’ perspective. We design policies’ content to flexibly define rights to use spectrum and support UAS operations. We design mechanisms to distribute policies reliably and securely. The results of this thesis could be useful to the Federal Aviation Administration (FAA) and the UAS industry in enabling more integration of UAS in the NAS. Additionally, the results of this thesis could motivate possible cognitive radio solutions in other areas such as vehicular communications or public safety.