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Metamaterial-Inspired CMOS Tunable Microwave Integrated Circuits For Steerable Antenna Arrays by Mohamed A.Y. Abdalla A thesis submitted in conformity with the requirements for the degree of Doctor of Philosophy Graduate Department of Electrical and Computer Engineering University of Toronto °c Copyright by Mohamed Abdalla 2009 Library and Archives Bibliothèque et Canada Archives Canada Published Heritage Direction du Branch Patrimoine de l’édition 395 Wellington Street 395, rue Wellington Ottawa ON K1A 0N4 Ottawa ON K1A 0N4 Canada Canada Your file Votre référence ISBN: 978-0-494-59036-2 Our file Notre référence ISBN: 978-0-494-59036-2 NOTICE: AVIS: The author has granted a non- L’auteur a accordé une licence non exclusive exclusive license allowing Library and permettant à la Bibliothèque et Archives Archives Canada to reproduce, Canada de reproduire, publier, archiver, publish, archive, preserve, conserve, sauvegarder, conserver, transmettre au public communicate to the public by par télécommunication ou par l’Internet, prêter, telecommunication or on the Internet, distribuer et vendre des thèses partout dans le loan, distribute and sell theses monde, à des fins commerciales ou autres, sur worldwide, for commercial or non- support microforme, papier, électronique et/ou commercial purposes, in microform, autres formats. paper, electronic and/or any other formats. The author retains copyright L’auteur conserve la propriété du droit d’auteur ownership and moral rights in this et des droits moraux qui protège cette thèse. Ni thesis. Neither the thesis nor la thèse ni des extraits substantiels de celle-ci substantial extracts from it may be ne doivent être imprimés ou autrement printed or otherwise reproduced reproduits sans son autorisation. without the author’s permission. In compliance with the Canadian Conformément à la loi canadienne sur la Privacy Act some supporting forms protection de la vie privée, quelques may have been removed from this formulaires secondaires ont été enlevés de thesis. cette thèse. While these forms may be included Bien que ces formulaires aient inclus dans in the document page count, their la pagination, il n’y aura aucun contenu removal does not represent any loss manquant. of content from the thesis. Metamaterial-Inspired CMOS Tunable Microwave Integrated Circuits For Steerable Antenna Arrays Mohamed A.Y. Abdalla Doctor of Philosophy, 2009 Graduate Department of Electrical and Computer Engineering University of Toronto Abstract This thesis presents the design of radio-frequency (RF) tunable active inductors (TAIs) with independent inductance (L) and quality factor (Q) tuning capability, and their application in the design of RF tunable phase shifters and directional couplers for wireless transceivers. The independent L and Q tuning is achieved using a modi¯ed gyrator-C architecture with an additional feedback element. A general framework is developed for this Q- enhancement technique making it applicable to any gyrator-C based TAI. The design of a 1.5V, grounded, 0.13¹m CMOS TAI is presented. The proposed circuit achieves a 0.8nH-11.7nH tuning range at 2GHz, with a peak-Q in excess of 100. Furthermore, printed and integrated versions of tunable positive/negative refractive index (PRI /NRI) phase shifters, are presented in this thesis. The printed phase shifters are comprised of a microstrip transmission-line (TL) loaded with varactors and TAIs, which, when tuned together, extends the phase tuning range and produces a low return loss. In contrast, the integrated phase shifters utilize lumped L-C sections in place of ii the TLs, which allows for a single MMIC implementation. Detailed experimental results are presented in the thesis. As an example, the printed design achieves a phase of -40o to +34o at 2.5GHz. As another application for the TAI, a recon¯gurable CMOS directional coupler is pre- sented in this thesis. The proposed coupler allows electronic control over the coupling coe±cient, and the operating frequency while insuring a low return loss and high iso- lation. Moreover, it allows switching between forward and backward operation. These features, combined together, would allow using the coupler as a duplexer to connect a transmitter and a receiver to a single antenna. Finally, a planar electronically steerable patch array is presented. The 4-element array uses the tunable PRI/NRI phase shifters to center its radiation about the broad- side direction. This also minimizes the main beam squinting across the operating bandwidth. The feed network of the array uses impedance transformers, which allow identical interstage phase shifters. The proposed antenna array is capable of continu- ously steering its main beam from -27o to +22o o® the broadside direction with a gain of 8.4dBi at 2.4GHz. iii Acknowledgments I would like to gratefully acknowledge the enthusiastic supervision of my advisors Pro- fessor Khoman Phang, and Professor George Eleftheriades for their continuous guid- ance, and inspiration. Throughout the course of my Ph.D. I have learned alot from them, and I will always remain indebted to them. I would like to thank Professor Khoman Phang for consistently being there for me, week after week to meet and dis- cuss all the di®erent aspects of this work. As for Professor George Eleftheriades, I would like to deeply thank him for his invaluable advice and feedback, without which this work would not have been accomplished. I would also like to extend my thanks the former and current graduate students in my research group as well as in the electro-magnetics group for their invaluable technical assistance and friendship from which I have learned alot. From the electronics group, I would like to thank Dr. Anas Hamoui, Dr. Ahmed Gharbiya, Dr. Mohammad Ha- jirostam, Joseph Aziz, Pradip Thachile, Masum Hossain, Farsheed Mahmoudi, Stephen Liu, Euhan Chong, Kentaro Yamamoto, Dr. Faisal Musa, Robert Wang, Dr. Afshin Haftbaradaran, Imran Ahmed, Navid Yaghini, Oleksiy Tyshchenko, Kevin Banovic, Tony Kao, David Allred, Akram Nafee, Trevor Caldwell, Samir Parikh, and Nasim Nikkhoo. From the Electro-magnetics group, I would like to thank Marco Antoniades for all the long hours we spent in technical discussions, and also Rubaiyat Islam, Dr. Omar iv Acknowledgements Siddiqui, Ashwin Iyer, Joshua Wong, and Peter Wang. Also, I would like to thank Tse Chan and Gerald Dubois for their continuous technical support. I would also like to extend my thanks the Canadian Microelectronics Corporation (CMC) for providing the fabrication facilities, and for NORTEL Networks, and the Natural Sciences and Engineering Research Council (NSERC) of Canada for ¯nancially supporting this work. Lastly, I would like to thank my beloved wife Aliaa, my parents, and my sister for their continuous support, and encouragement throughout the course of my Ph.D., and last but not least, I would like to thank my daughter Jana, whom without knowing has been a motivation for my accomplishments. The least I can do is to dedicate this work to them. v List of Related Publications The material presented in this thesis has been presented in part in the following journal and conference publications. Journal Publications 1. M. Abdalla, K. Phang, and G. V. Eleftheriades, \A 0:13¹m CMOS phase shifter using tunable positive/negative refractive index transmission line," IEEE Microw. Wireless Components Lett., Vol. 16, no. 12, pp. 705-707, Dec. 2006. 2. M. Abdalla, K. Phang, and G. V. Eleftheriades, \Printed and integrated CMOS positive/negative refractive-index phase shifters using tunable active inductors," IEEE Trans. Microw. Theory and Tech., Vol. 55, no. 8, pp. 1611-1623, August 2007. 3. M. Abdalla, K. Phang, and G. V. Eleftheriades, \A compact highly- recon¯g- urable CMOS MMIC directional coupler," IEEE Trans. Microw. Theory and Tech., Vol. 56, no. 2, pp. 305-3019, Feb. 2008. 4. M. Abdalla, K. Phang, and G. V. Eleftheriades, \A Planar Electronically Steer- able Patch Array Using Tunable PRI/NRI Phase Shifters," IEEE Trans. Microw. Theory and Tech., accepted for publication Dec. 2008. vi Conference Publications 1. M. Abdalla, and K. Phang , \A 0:13¹m CMOS active inductor based on a modi- ¯ed gyrator-C architecture," Micronet Annual Workshop, Ottawa, Canada, May 2005. 2. M. Abdalla, G. V. Eleftheriades, and K. Phang, \A di®erential 0:13¹m CMOS active inductor for high frequency phase shifters," Proc. IEEE Circuits and Sys- tems ISCAS 06, Kos, Greece, pp. 3341-3344, May 2006. 3. M. A. Y. Abdalla, K. Phang, and G. V. Eleftheriades, \a tunable metamaterial phase-shifter structure based on a 0:13¹m CMOS active inductor," Proc. 36th European Microwave Conf., Manchester, Great Britain, pp. 325-328, Sept. 2006. 4. M. A. Y. Abdalla, K. Phang, and G. V. Eleftheriades, \A bi-directional elec- tronically tunable CMOS phase shifter using the high-pass topology," 2007 IEEE MTT-S Int. Microwave Symp. Dig., Honolulu, Hawaii, pp. 2173-2176, June 2007. 5. M. A. Y. Abdalla, K. Phang, and G. V. Eleftheriades, \A steerable series-fed phased array architecture using tunable PRI/NRI phase shifters," Invited paper, Int. Workshop on Antenna Tech. iWAT 08, Chiba, Japan, March 2008. vii Contents List of Figures xii List of Tables xviii List of Acronyms xx List of Symbols xxii 1 Introduction 1 1.1 Overview . 1 1.2 Phased Antenna Array Front-Ends . 1 1.3 Thesis Scope and Outline . 5 2 Background 8 2.1 Metamaterials . 8 2.1.1 History . 8 2.1.2 Metamaterial Applications . 10 2.2 Tunable Inductors . 11 2.2.1 MEMS Tunable Inductors . 11 2.2.2 Varactor-Based Tunable Inductors . 12 2.2.3 Transmission-Line Tunable Inductors . 13 2.2.4 Gyrator-C Tunable Inductors . 13 2.3 Phase Shifters . 22 2.3.1 Switched-Line Phase Shifters . 23 viii Contents 2.3.2 Reflection-Type Phase Shifters . 24 2.3.3 Transmission-Type Phase Shifters . 25 2.3.4 Lumped-Element L-C Phase Shifters .
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