الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Since their formal introduction in 1975 by Holland, Genetic algorithms (GA) have been applied to a variety of fields medicine, engineering, business .. etc to optimize functions that can not be easily optimized by traditional methods. Other applications of GAs include automatic programming and simulation of natural systems
The aim of this thesis is to study the use of Genetic algorithms in designing antenna atTays, enhancing their performance and recovering element failure by optimizing the feeding of array elements fulfilling specified requirements in pattern
under certain constrains.
Chapter I is general introduction showing the reasons of using Genetic algorithms in antenna atTay synthesis and their advantages compared to other methods
Chapter II is an overview of antenna arrays showing the analysis of linear, planar and circular arrays and their synthesis
. In chapter III genetic algorithms were presented showing simple genetic algorithm along with its extensions and improvements including elitist strategy, steady state genetic algorithm and parallel genetic algorithm.
Chapter IV deals with genetic algorithm as an antenna synthesis method presenting problem formulation in genetic view and the use of genetic algorithm to achieve Dolf-Chebyshev pattern It also studies the effect of different genetic algorithm operators, as well as the use of parallel genetic algorithm to solve the problem_
Chapter V concerns with pattern shaping and enhancement uSll1g genetic algorithm by cOiltrolling amplitude, phase of elements’ feeding and their spacing for Gauss and exponential pattern along with beam enhancement for Chebyshev pattern
Chapter VI studies the use of genetic algorithm in element failure restoration showing the effect of element failure in the pattern shape of a Chebyshev array. Employing genetic algorithm to restore both boundary element failure and central element failure using both amplitude and phase control is presented.
Finally, a conclusion discussing the results of this work and the future proposals is presented in chapter VII.