Read Books Online and Download eBooks, EPub, PDF, Mobi, Kindle, Text Full Free.
Information Gathering And Use In Constrained Genetic Algorithm For Antenna Design
Download Information Gathering And Use In Constrained Genetic Algorithm For Antenna Design full books in PDF, epub, and Kindle. Read online Information Gathering And Use In Constrained Genetic Algorithm For Antenna Design ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis Information Gathering and Use in Constrained Genetic Algorithm for Antenna Design by : Pichitpong Soontornpipit
Download or read book Information Gathering and Use in Constrained Genetic Algorithm for Antenna Design written by Pichitpong Soontornpipit and published by . This book was released on 2005 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Automated Design and Optimization of Wire Antennas Using Genetic Algorithms by : Derek Scott Linden
Download or read book Automated Design and Optimization of Wire Antennas Using Genetic Algorithms written by Derek Scott Linden and published by . This book was released on 1997 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: A Genetic Algorithm (GA) has been used in conjunction with the Numerical Electromagnetics Code, Version 2 (NEC2) to create and optimize atypical wire antenna designs with impressive characteristics. Antenna design parameters are encoded into an ordered series of numbers and/or symbols analogous to a biological chromosome. A cost function that quantifies how well a design meets the engineer's specifications is created. The GA uses these to generate and evaluate a population of designs. The most successful designs are then promoted and mixed through mating and mutation, while poor designs are removed. This process, difficult to trap in local minima, continues until convergence criteria are met, generally yielding excellent designs with no user intervention or initial guesses. Three antennas have been optimized: a monopole loaded with a modified folded dipole, the Yagi antenna, and the crooked-wire genetic antenna. Prior study of the loaded monopole had shown hemispherical coverage was possible. The GA found an asymmetric loaded monopole with an average variation in gain over the hemisphere of only 0.4dB, confirmed by measurement. GA-optimized Yagi antennas surpassed the gain of conventional Yagis by about 1dB, improvement also confirmed by measurement. The GA designed a Yagi with a beamwidth of 50 deg -60 deg, sidelobes nearly 25dB down, and a 14% bandwidth-specifications difficult to achieve using conventional techniques. The crooked-wire genetic antenna is several wires joined in series; locations and lengths are determined by the GA. Optimization for hemispherical coverage with right-hand circular polarization (RHCP) produced highly unusual shapes unrealizable using a conventional approach. RHCP hemispherical coverage was achieved with less than 4dB variation. Measurements verify the results.
Book Synopsis Military Antenna Design Using Simple and Competent Genetic Algorithms by :
Download or read book Military Antenna Design Using Simple and Competent Genetic Algorithms written by and published by . This book was released on 2005 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Dissertation Abstracts International by :
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2006 with total page 860 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Military Antenna Design Using Simple and Competent Genetic Algorithms by : Edward E. Altshuler
Download or read book Military Antenna Design Using Simple and Competent Genetic Algorithms written by Edward E. Altshuler and published by . This book was released on 2004-06-01 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past decade, the Air Force Research Laboratory (AFRL) antenna Technology Branch at Hanscom AFB has employed the simple genetic algorithm (SGA) as an optimization tool for a wide variety of antenna applications. Over roughly the same period, researchers at the Illinois Genetic Algorithm Laboratory (IlliGAL) at the University of Illinois at Urbana-Champaign have developed GA design theory and advanced GA techniques called competent genetic algorithms that solve hard problems quickly, reliably, and accurately. Recently, under the guidance and direction of the Air Force Office of Scientific Research (AFOSR), the two laboratories have formed a collaboration, the common goal of which is to apply simple, competent, and hybrid GA techniques to challenging antenna problems. This paper is composed of two parts. The first part of this paper summarizes previous research conducted by AFRL at Hanscom for which SGAs were implemented to obtain acceptable solutions to several antenna problems. The second part of this paper starts by briefly reviewing the design theory and design principles necessary for the invention and implementation of fast, scalable genetic algorithms. A particular procedure, the hierarchical Bayesian optimization algorithm (hBOA) is then briefly outlined, and the remainder of the paper describes collaborative efforts of AFRL and IlliGAL to solve more difficult antenna problems.
Book Synopsis Antenna design optimitzation using a real-coded genetic algorithm[ by : Raquel Rodríguez Suquet
Download or read book Antenna design optimitzation using a real-coded genetic algorithm[ written by Raquel Rodríguez Suquet and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Antenna Design Optimization by : T. L. Pitzer
Download or read book Antenna Design Optimization written by T. L. Pitzer and published by . This book was released on 2007-12-01 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt: A Genetic Algorithm (GA) is used in concert with the Numerical Electromagnetics Code, Version 4 (NEC4) to create and optimize typical wire antenna designs including single elements and arrays, the result being antennas with impressive characteristics. Previous work in antenna optimization is discussed as it relates to this method. The method shown applies to antennas whose basis of designs are both the Yagi-Uda antenna and the Log Periodic Dipole Array (LPDA) antenna. Also covered are applications in Passive Remote Sensing (PRS) and Over the Horizon Radar (OTHR). With color illustrations. Chapter titles are ...(1) Introduction ...(2) Background in Antenna Design and Optimization with Genetic Algorithms ...(3) Methodology for Designing, Testing and Analyzing Antennas ...(4) Experimental Results and Analysis of Synthesized Antennas ...(5) Conclusions ...(6) Appendix A: How to Use GNEC inside of iSIGHT ...(7) Appendix B: GNEC Code.
Book Synopsis Use of Genetic Algorithms in Microstrip Antenna Design Using the Cavity Model by : Jayanthi Srinivasan
Download or read book Use of Genetic Algorithms in Microstrip Antenna Design Using the Cavity Model written by Jayanthi Srinivasan and published by . This book was released on 1999 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis The Significance of Genetic Representation in Genetic Antenna Design by :
Download or read book The Significance of Genetic Representation in Genetic Antenna Design written by and published by . This book was released on 2003 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Genetic algorithms have been shown to be effective in the design of small antennas. However, their effectiveness depends on both the mechanisms of the genetic algorithm and the genetic representation of the problem. Here we present three genetic chromosome representations for a small antenna design problem (lowest VSWR for a specified h/lambda cube size) and compare the results of the three optimization processes. Our work shows that different chromosome representations lead to solutions in different, overlapping subclasses, and that an important consideration in genetic antenna design is finding a simple chromosome representation which is capable of representing the subclass containing the "optimal" solution. Our initial results show that the chromosome design itself is an important factor in successful genetic antenna design.
Book Synopsis Antenna Design Using Optimization Techniques Over Various Computaional Electromagnetics by : Fathi M. A. Abdussalam
Download or read book Antenna Design Using Optimization Techniques Over Various Computaional Electromagnetics written by Fathi M. A. Abdussalam and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Microstrip Antenna Design Using Genetic Algorithm by : Laurent Foissey
Download or read book Microstrip Antenna Design Using Genetic Algorithm written by Laurent Foissey and published by . This book was released on 2001 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Survival of Infeasible Designs During Constrained Genetic Algorithm Optimization by : William A. Crossley
Download or read book Survival of Infeasible Designs During Constrained Genetic Algorithm Optimization written by William A. Crossley and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Genetic Algorithm Optimization Applied to Planar and Wire Antennas by : Andrea M. Wyant
Download or read book Genetic Algorithm Optimization Applied to Planar and Wire Antennas written by Andrea M. Wyant and published by . This book was released on 2007 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Antenna design has grown more stringent and difficult over the years as the world becomes strictly a wireless environment. The inherent tradeoffs that exist between gain, radiation pattern, bandwidth, and physical size and the multiple parameters that must be considered make antenna design a lengthy and tedious process. Methods have been devised which automate this complex process of antenna optimization through the use of genetic algorithms, particle swarm optimization, and simulated annealing. Genetic algorithms are capable of handling a large number of design parameters and work for optimization problems that have discontinuous or non-differentiable multi-dimensional solution spaces, making them ideal for antenna optimization. In the present work, a genetic algorithm has been used for size reduction in microstrip patch antennas and design tradeoff optimization between beamwidth and gain in helical antennas. A method for reducing the size of microstrip patch antennas by up to 75% by removing rectangular and circular slots from the metal of the microstrip patch is presented. A solid patch antenna that resonates at 10 GHz is forced to resonant at 6 GHz through the removal of the different shaped slots. Given the number and shape of the slots, the genetic algorithm is used to optimize the size and location of the slot on the patch. The designs are obtained by interfacing the genetic algorithm and Ansoft High Frequency System Simulator (HFSS) and validated through design, construction, and testing. High gain, with broad half-power beamwidths (HPBW) is traditionally extremely difficult to achieve due to the inherent tradeoff between the two. A genetic algorithm has been applied to design a helical antenna with a gain of 10 dB and HPBWs of 60 degrees. In order to achieve this, three physical parameters of the helix have been changed, namely the pitch, helix radius, and the ground plane geometry. The second objective is to create an antenna that displays different HPBWs in the two radiation planes. This could be extremely useful in many communication environments and there is yet no existing method to achieve this. The genetic algorithm produced a helical antenna that shows a 19 degrees difference in HPBW between the two radiation planes, while still displaying a 7 dB gain and low side lobes. Numerical Electromagnetic Code 4 (NEC4) is used, and a method of communication between MATLAB and NEC4 has been developed to make the genetic algorithm optimization possible"--Abstract.
Book Synopsis Application of Evolutionary Algorithms and Neural Network Concepts to the Design of Low-Cost, Wideband Antenna Arrays by :
Download or read book Application of Evolutionary Algorithms and Neural Network Concepts to the Design of Low-Cost, Wideband Antenna Arrays written by and published by . This book was released on 2007 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper describes the application of biologically-inspired algorithms and concepts to the design of wideband antenna arrays. In particular, we address two specific design problems. The first involves the design of a constrained-feed network for a Rotman-lens beamformer. We implemented two evolutionary optimization (EO) approaches, namely a simple genetic algorithm (SGA) and a competent genetic algorithm. We conducted simulations based on experimental data, which effectively demonstrate that the competent GA outperforms the SGA (i.e., finds a better design solution) as the objective function becomes less specific and more general. The second design problem involves the implementation of polyomino-shaped subarrays for sidelobe suppression of large, wideband planar arrays. We use a modified screen-saver code to generate random polyomino tilings. A separate code assigns array values to each element of the tiling (i.e., amplitude, phase, time delay, etc.) and computes the corresponding far-field radiation pattern. In order to conduct a statistical analysis of pattern characteristics vs. tiling geometry, we needed a way to measure the similarity between two arbitrary tilings to ensure that our sampling of the tiling space was somewhat uniformly distributed. We ultimately borrowed a concept from neural network theory, which we refer to as the dot-product metric, to effectively categorize tilings based on their degree of similarity.
Book Synopsis Fundamentals of Aperture Antennas and Arrays by : Trevor S. Bird
Download or read book Fundamentals of Aperture Antennas and Arrays written by Trevor S. Bird and published by John Wiley & Sons. This book was released on 2016-01-19 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is intended as an advanced text for courses in antennas, with a focus on the mature but vital background field of aperture antennas. The book is aimed at final year, MSc, PhD and Post-Doctoral students, as well as readers who are moving from academia into industry, beginning careers as wireless engineers, system designers, in R&D, or for practising engineers. It assumes the reader has undertaken an earlier course of study on Maxwell's equations, fields and waves. Some of these topics are summarised in the early few chapters in order to provide continuity and background for the remaining chapters. The aperture antennas covered include the main types of horns, reflectors and arrays as well as microstrip patches, reflectarrays and lenses. To provide more than a superficial treatment of arrays, the topic of mutual coupling is covered in greater detail than most similar books in the area. Also included is an introduction to arrays on non-planar surfaces, which is of importance for applications that involve curved surfaces such as in aerodynamics or for making aperture antennas unobtrusive. A chapter is included on some modern aperture antennas to illustrate design techniques beyond the most common types of aperture antennas described in the early chapters. This is to show where advances have recently been made and where they could be improved in the future. Also included are selected topics of a practical nature for aperture antennas, namely fabrication and measurement.
Book Synopsis Genetic Algorithms in Antenna Design with Applications to NVIS Systems by : Wen-Chung Liu
Download or read book Genetic Algorithms in Antenna Design with Applications to NVIS Systems written by Wen-Chung Liu and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis The use of the genetic algorithm approach in the design of ultra-wideband antennas by : Aaron Jon Kerkhoff
Download or read book The use of the genetic algorithm approach in the design of ultra-wideband antennas written by Aaron Jon Kerkhoff and published by . This book was released on 2001 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt:
