<p>Recent advances in electromagnetics introduced tools that enable the creation of arti-</p><p>cial electromagnetic structures with exotic properties such as negative material pa-</p><p>rameters. The ability to express these parameters has experimentally demonstrated</p><p>using passive metamaterial structures. These structures, based on their passivity and</p><p>resonant properties, are typically associated with high loss and signicant bandwidth</p><p>limitations.</p><p>Enhancing and further exploring novel electromagnetic properties can be done</p><p>through embedding active circuits in the constitutive unit cells. Active elements</p><p>are able to supplement the passive inclusions to mitigate and overcome loss and</p><p>bandwidth limitations. The inclusion of these circuits also signcantly expands the</p><p>design space for the development of functional metamaterials and their potential</p><p>applications.</p><p>Due to the relative diculty of designing active circuits compared with passive</p><p>circuits, using active circuits in the construction of metamaterials is still an under-</p><p>developed area of research. By combining the two elds of active circuit design and</p><p>metamaterial design, we aim ll the functional active metamaterial design space.</p><p>This document provides the basis for understanding the design and synthesis of</p><p>functional active metamaterials.</p><p>To provide necessary background matter, chapter 1 will function as an introduc-</p><p>tion chapter, discussing how active electromagnetic metamaterials are created and characterized. There are also several required design techniques necessary to suc-</p><p>cessfully engineer a functional active metamaterial. The introduction will emphasize</p><p>on linking metamaterial unit cell response with RF/analog circuit design with a brief</p><p>introduction to the semiconductor physics important to aid in the understanding of</p><p>the full active metamaterial design and fabrication process.</p><p>The subsequent chapters detail our specic contributions to the eld of func-</p><p>tional active RF metamaterials. Chapter 2 introduces and characterizes a meta-</p><p>material designed to have a tunable quality factor (tunable resonant bandwidth).</p><p>This metamaterial is essentially passive but demonstrates the transistor's versatility</p><p>as a combination of tunable elements, motivating the use of embedding transistors</p><p>in metamaterials. After establishing a simple application of a transistor in a pas-</p><p>sive metamaterial, chapter 3 outlines the design and characterization of an active</p><p>metamaterial exhibiting the properties of loss cancellation and gain. Chapter 4 in-</p><p>troduces another active metamaterial with the ability to self-adapt to an incident</p><p>signal. Within the self-adapting system, several complex RF circuit systems are</p><p>simulatenously developed and implemented such as a self-oscillating mixer and a</p><p>phase locked loop. Conclusions and additional suggested future research directions</p><p>are discussed in chapter 5.</p><p>There are also several appendices attached at the end of this document that are</p><p>meant to assist future graduate students and other readers. The additional topics</p><p>include the experimental verication of a passive magnetic metamaterial acting as a</p><p>near eld parasitic, the stabilization and measurement of a tunnel diode, a discussion</p><p>on the challenges of realizing active inductors from discrete components, and a basic</p><p>strategy for creating a non-volatile metamaterial. It is my aim for these appendices</p><p>to help provide additional inspiration for future studies within the eld.</p> / Dissertation

Nous étudions la mise en oeuvre d ‘antenne à balayage électronique dédiés aux applications de communications par satellite géostationnaire. Les structures développées sont adaptées pour être embarquées dans un avion ou un train. L'architecture de l'antenne développée est constituée d’un double réseau linéaire dans deux dimmensions transverses. Le balayage dans chaque réseau linéaire est assuré par des lignes coplanaires à métamateriaux contrôlées par varactor. Nous porposons de nouvelles méthodes de caracterisation des discontinuités en ligne coplanaire pour la conception de la ligne. De plus, un système de prélèvement d'énergie a dû être conçu afin d'alimenter des éléments rayonnants et testé avec différentes antennes patch. Enfin, nous envisageons la co-intégration des structures rayonnantes et des lignes CRLH ainsi que le contrôle électronique par les diodes. / We are studying the implementation of 'Scanning Antenna dedicated to the applications of satellite communications geostationary. The structures developed are suitable for to be on board an airplane or a train. The architecture of the antenna developed consists of a double linear network in two transverse dimmensions. The scan in each network is provided by the lines coplanar to metamaterials controlled by varactor. We porposons of new methods characterization of discontinuities coplanar online for the line design. In addition, a energy harvesting system has be designed to feed radiating elements and tested with patch different antennas. Finally, we are considering co-integration radiating structures and CRLH lines as well as control electronic by the diodes.