الفهرس 
Chapter 1 IntroductionOnly 14 pages are availabe for public view
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Abstract
The key characteristic and the big challenge at any cellular system are to meet the needs of the users with high QOS (Quality of Service), providing large coverage area and increasing system capacity that are represented a big challenge especially with the limited available spectrum. A new mobile generation has appeared every 10th year started with first Generation (1stG) that was launched in 1979 by NTT (Nippon Telegraph and Telephone) in Japan and was based on analogue transmission technique till LTE (Long Term Evolution Term Evolution that represents the 4thG and it is deployed by the 3GPP (3rd Generation Partnership Project). All these generations are seeking for increasing system capacity, providing large coverage area with efficient use of limited spectrum. In this thesis, the problem of enhancing coverage and increasing system capacity are introduced in LTE system based on Cognitive Radio (CR) technique. Firstly, a proposed optimal system design of the Strict Fractional Frequency Reuse (S-FFR) in Orthogonal Frequency Division Multiple Access Technique (OFDMA) based on wireless communication networks where the cells are partitioned into spatial regions with different frequency reuse factors and evaluating S-FFR which represents a type of FFR deployments that is presented with four different system models by changing the inner-cell shape for each model and choosing the best model that gives best Throughput (THR) and least blocking probability (Pb). Secondly, introducing new multi-level power control algorithm to increase system capacity and make full use of all available channels. Proposed system will be compared to the traditional one through blocking probability and channel utilization metrics. Finally, improving coverage and mobility using Femto-cell based on CR in LTE as Femtocells or short range are introduced lately for indoor coverage extension, as it offers low power and low cost due to reduce cell size and the coverage distance per cell. Femto-cells can be used to overcome dead zones or uncovered regions to enhance the coverage, it can cooperate with macro-cell using the same band or different one. Using CR is to solve the problems of spectrum inefficiency which CR provides the capability to use or share the spectrum in an opportunistic manner, dynamic spectrum access techniques allow the CR to operate in the best available channel.