Antennas represent a critical technology in any of these wireless systems. Not only do they directly affect the received power of the system, they are also typically the largest and most visible part. Recently, the need for low-cost, low-profile, and lightweight antenna in the frequency range of the microwave/millimeter wave/THz band has regained momentum. "Basic Principles of Fresnel Antenna Arrays" provides us a with the basics of the various Fresnel Antenna approaches, in order to achieve low-cost, low-profile, and lightweight antenna in the microwave/millimeter wave band. A potential solution of the antenna problem lies in using lens technology in an array. The Fresnel zone plate lens (FZPL) antenna is in particular an interesting candidate for the array element. The limiting focusing properties of FZPL including subwave length focus are described in detail. The book further presents a novel hexagonal FZPL antenna which can be more effectively packed in an array due to its shape. Before considering the hexagonal FZPL antenna in an array, the authors investigate two ideas, described as methods to potentially improve the radiation characteristics. The first idea is to change the reference phase of the Fresnel zone radii - a novel free parameter in the usual design of zone plate’s lenses and antennas. To further improve the radiation characteristics of the hexagonal FZPL antenna, a technique involving Fresnel zone rotation is investigated. The book is of interest for designers of optical systems because, taking scaling effects into account, the characteristics of diffractive quasioptical elements are valid for diffractive focusing elements of integrated optics.
Timberlake claimed in 1980 that a fundamental problem with Singer's work is the lack of an adequate definition of suffering ...
3. D. Layne. 2013. Tree Fruit: Protecting Your Investment. American/Western Fruit Grower, September/October. 4. R. Snyder and J. Melu-Abreu. 2005. Frost ...
At that time, these were in the low $10s of millions. ... be a good partner going forward, even though it takes longer to get the deal done," offered Chess.
[ 59 ] S. Kotz , T. J. Kozubowski , and K. Podgorski , The Laplace ... valued signal processing : The proper way to deal with impropriety , ” IEEE Trans .
Some documents are annotated; some are left without annotations to provide more flexibility for instructors. This booklet can be packaged at no additional cost with any Longman title in technical communication.
Chemistry: An Introduction to General, Organic, and Biological Chemistry; Chemistry Study Pack Version 2.0 CD-ROM; The Chemistry of Life CD-ROM;...
The emission rates for ammonia (Casey et al., 2006): • Layers: 116 g NH3 per AU (AU or animal unit or 500 kg). • Broilers: 135 g NH3 per AU (AU or animal unit or 500 kg). Emission rates in different reports vary from less than either 10 ...
[45] B.F. Hoskins, R. Robson, “Design and construction of a new class of scaffolding-like materials comprising infinite polymeric frameworks of 3D-linked molecular rods. A reappraisal of the zinc cyanide and cadmium cyanide structures ...
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ACCOUNTING Christopher Nobes ADVERTISING Winston Fletcher AFRICAN AMERICAN RELIGION Eddie S. Glaude Jr AFRICAN HISTORY ... Hugh Bowden ALGEBRA Peter M. Higgins AMERICAN HISTORY Paul S. Boyer AMERICAN IMMIGRATION David A. Gerber AMERICAN ...