Reflectarray antennas refer to the class of radiating structures that are comprised of an array of radiating elements, re-radiating the energy that is impinged on them from one or more radiating feeds that are located in free space. The constituent radiators that build a reflectarray can be shaped to bring about some flexibility in the way that antenna operates such as multi band/polarization operation. The printed nature of these elements allow integration of active elements that can further enhance the functionality of the reflectarray. This allows for capabilities such as power amplification, adaptive beam shaping, and beam switching. This resource presents readers with design guidelines along with an ample amount of material on different types of reflectarrays and methods of analysis. This book begins with introductory material on reflectarray antennas and progresses to the presentation of state-of-the-art research in the field. A direct comparison with conventional reflector antennas is provided, focusing on conventional efficiency figures of reflectors. Moreover, this book offers remarks on the future direction of reflectarray research and also potential applications of the technology in face of the emergence of new fabrication techniques to accommodate both passive and active elements.
Introduction - General Background. Why Reflectarrays? The Structure of the Book. ; Fundamentals of Reflectarray and General Design Guidelines - General Design Equations. Aperture Efficiency of Reflectarray and Comparison with Conventional Parabolic Reflector. Simplest Reflectarray Cell Element: Microstrip Patch. ; Different Types of Cell Elements for Reflectarrays - Resonant Cell Elements. Loop Elements. Phase Shift by Loading Resonant Elements. Volumetric Cell Elements. Subwavelength, Coupled Resonant Elements. ; Different Types of Reflectarrays - Multiband Reflectarray. Circularly Polarized Reflectarrays. Folded Reflectarray. Power Combining and Beam Splitting. Subreflectarray Structures. Beam Shaping. ; Numerical Methods: Pathway to a Better Understanding of Reflectarrays - Application on the Method of Moment in the Analysis of Reflectarrays. Application of Circuit Models in the Analysis of Reflectarray Cell Element. Calculation of the Radiation Pattern of a Reflectarray. Application of Commercial Software in the Design and Analysis of Reflectarrays. The Infinite-from-Finite Method. Characteristic Mode Analysis of Periodic Structures. ; Reflectarray Bandwidth -Introduction. Bandwidth Limitation by the Reflectarray Element. Multiresonant Elements. Subwavelength Elements. Bandwidth Limitation by Differential Spatial Phase Delay. Impact of the Feed Position on the Bandwidth of Broadband Reflectarrays. ; Reflectarrays on Lossy Substrates - Introductory Remarks. A Description of the Loss Mechanism in Reflectarray Elements. Cataloging Elements Based on Loss Performance. Frequency Dispersion of the Reflection Phase and Its Relationship with Loss. High-Performance Reflectarrays Using Lossy Substrates. Concluding Remarks. ; Transmitarray -Introduction. Antenna-Filter-Antenna Transmitarray. Multilayer Transmitarray Using Matching Impedance.; New Techniques for Beam Switching or Steering in Reflectarray and Transmitarray -Introduction. Mechanical Techniques for Beam Scanning of Reflectarray and Transmitarray. Reflectarray Beam Scanning Using Reconfigurable Materials. Electronically Controlled Reflectarray Antennas. Dual Reflectarray Antenna for Beam-Scanning Application; Fabrication Technologies - Outline of Reflectarray Fabrication Technologies. Element Performance and Minimum Feature Size. The Impact of Etching Tolerance on Reflectarray Performance. Novel Designs Employing the Sole Use of Material Routing. Inkjet-Printed Reflectarrays. ; Conclusion and Future Directions ;
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Mohammad Reza Chaharmir
Mohammad Reza Chaharmir is a research scientist at the Communications Research Centre Canada. He earned his Ph.D. from University of Manitoba.
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Jonathan Ethier
Jonathan Ethier is a research engineer at the Communications Research Centre Canada. He earned his Ph.D. from University of Ottawa.
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Jafar Shaker
Jafar Shaker is a research scientist at the Communications Research Centre Canada. He earned his Ph.D. from University of Mantioba.