A Day in the Life of the RF Spectrum

There is a misguided perception that RF spectrum space is fully allocated and fully used though even a superficial study of actual spectrum usage by measuring local RF energy shows it largely empty of radiation. Traditional regulation uses a fence-off policy, in which competing uses are isolated by frequency and/or geography. We seek to modernize this strategy. Given advances in radio technology that can lead to fully cooperative broadcast, relay, and reception designs, we begin by studying the existing radio environment in a qualitative manner. We wish to objectively understand the purpose of a particular transmission, its threshold of allowable interference, and whether anyone is attempting to receive it. We wish to propose ways in which cognitive radio systems might coexist with legacy radio systems. In Chapter 1, we review the conditions that led to the current regulatory climate. Chapter 2 discusses the purpose of this thesis and how the work done relates to cognitive radio technologies. Chapter 3 discuses the design of data capture and analysis modules used to better understand RF spectrum space usage. Chapter 4 applies the software modules to a range of spectrum space and evaluates the results. Thesis Supervisor: Andrew B. Lippman Title: Senior Research Scientist of Media Arts and Sciences