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[...]... array here, however, to mean an array of radiators distributed with equal spacing along the periphery of a circle, as in Figure 2.1 (b) Conformal Array Antenna Theory and Design By Lars Josefsson and Patrik Persson © 2006 Institute of Electrical and Electronics Engineers, Inc 15 16 CIRCULAR ARRAY THEORY (a) (b) Figure 2.1 A circular planar array (a), and a circular (ring) array (b) Circular array antennas... The circular array antenna can be seen as an elementary building block of conformal array antennas with rotational symmetry, just as the linear array is a building block of planar array antennas Fundamental characteristics of planar arrays can be learned from studies of linear array antennas Similarly, by studying circular arrays we can understand some basic aspects of conformal array antennas, especially... IEEE Standard Definition of Terms for Antennas (IEEE Std 145-1993) gives the following definition: 2.74 conformal antenna [conformal array] An antenna [an array] that conforms to a surface whose shape is determined by considerations other than electromagnetic; for example, aerodynamic or hydrodynamic 2.75 conformal array See: conformal antenna Strictly speaking, the definition includes also planar arrays... the practicing antenna and systems engineer in understanding and working with these interesting antennas Each chapter starts with some introductory material, that is, the basic concepts that are essential to get an understanding of the more advanced aspects The first three chapters present an overview of conformal array principles and applications, including the theory for circular arrays and phase mode... Workshop on Conformal Antennas, The Hague, The Netherlands, 24–25 April Wingert D A and Howard B M (1996), “Potential Impact of Smart Electromagnetic Antennas on Aircraft Performance and Design, ” in NATO Workshop on Smart Electromagnetic Antenna Structures, Brussels, November, pp 1.1–1.10 Vourch E., Caille C., Martin M J., Mosig J R., Martin A., and Iversen P O (1998), Conformal Array Antenna for... Synthesis of Circular Arrays,” The Radio and Electronic Engineer, pp 341–355, November 13 2 CIRCULAR ARRAY THEORY In this chapter, we present an overview of the basics of circular array theory This will serve as a background to the chapters on conformal array characteristics, design, and synthesis We will also discuss the concept of phase modes, which is a useful tool for the understanding of the performance... “Phased Array Radars in France: Present and Future,” IEEE International Symposium on Phased Array Systems and Technology, 15–18 October, pp 458–462 Davies D E N (1981), “Circular Arrays: Their Properties and Potential Applications,” in IEE Proceedings of 2nd International Conference on Antennas and Propagation, April, pp 1–10 Davies D E N (1983), “Circular Arrays,” in Rudge et al (eds.): The Handbook of Antenna. .. electromagnetic.” This is, however, not common practice Usually, a conformal antenna is cylindrical, spherical, or some other shape, with the radiating elements mounted on or integrated into the smoothly curved surface Many Conformal Array Antenna Theory and Design By Lars Josefsson and Patrik Persson © 2006 Institute of Electrical and Electronics Engineers, Inc 1 2 INTRODUCTION variations exist, though,... 2.2.1 Linear Arrays Although our purpose is to study circular arrays, we will start with a short introduction to linear arrays [Rudge et al 1983, Kummer 1992, Mailloux 1994] Several aspects of circular array theory build on the previously developed theory for linear arrays It is also informative to point out similarities and differences between the linear and circular cases Much of linear array theory can... Rahim T., Guy J R F., and Davies D E N (1981), “A Wideband UHF Circular Array, ” in IEE Proceedings of 2nd International Conference on Antennas and Propagation, pp 447–450, part 1, April Rai E., Nishimoto, S., Katada, T., and Watanabe, H (1996), “Historical Overview of Phased Array Antenna for Defense Application in Japan,” in IEEE International Symposium on Phased Array Systems and Technology, 15–18 . www.wiley.com. Library of Congress Cataloging-in-Publication Data is available. ISBN-13 97 8-0 -4 7 1-4 658 4-3 ISBN-10 0-4 7 1-4 658 4-4 Printed in the United States of America. 10987654321 ffirs.qxd. fundamental principles behind conformal antennas, as well as hands-on information necessary for the analysis and design of conformal antenna arrays. Graphical illustrations