الفهرس 
Chapter 1: IntroductionOnly 14 pages are availabe for public view
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Abstract
Wireless communication systems suffer from limited bandwidth, that decrease data rate, number of subscribers and security. Space Division Multiple Access (SDMA) is one of the multiple access techniques, which have become widely accepted to overcome limitation of bandwidth. In this dissertation, a certain DOA angles were predetermined and the main aim is adjusting the beam-former to control the radiation pattern of this closed loop smart antenna system. This dissertation suggests a two novel optimization algorithm to enhance the performance of a smart antenna system for wireless communication system especially High Altitude Platform (HAP). The first one is a hybrid algorithm between Gravitational Search Algorithm (GSA) and Particle Swarm Optimization (PSO). The second one is more powerful technique which is called Grey Wolf Optimization (GWO). Finally, the pattern synthesis of unequally spaced linear antenna arrays is optimized by Hybrid PSOGSA with null placement in certain directions and/or side-lobe levels.