الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
For achieving higher data rates, 3G and 4G cellular systems are required to provide good coverage to enhance the system performance. However, research results clarify that two¬thirds of subscribers suffer from inappropriate indoor signal penetration, which actually leads to poor coverage for indoor users and the full data capacity is not achieved as guaranteed. In 4G systems, the advantage of high-speed data services will definitely diminishes by the poor indoor coverage.
Femtocells have been pointed out by the industry as a good solution, not only to overcome the indoor coverage problem but also to deal with the growth of data traffic within macrocell. As a result, the deployment of femtocells in the existing macrocell networks and 4G networks will significantly increase because femtocells enhance coverage and capacity in indoor environments. However, the allocation of spectrum resources and the avoidance of intercell interference are the most urgent challenges that operators face before femtocells can be widely deployed in licensed spectrum bands. The objective of this thesis is to find solutions for effective operation of macrocells and femtocells in the same licensed band(s). Coordinated scheduling and coordinated multipoint transmission between co-layer cells and cross-layer cells have been applied. The simulation results illustrate that, based on the proposed approaches, the deployment of femto-layer over the existing macro¬layer in the same licensed band may not cause serious problems to macro-layer; on the contrary, by carefully planning, the macro-layer performance can even be enhanced.Moreover, most of the previous femtocells studies concentrated mainly on the femtocell business model aspects and the few available technical works were mainly theoretical analysis and results. There is an obvious need for some simulations in an environment that is close to the real-life network. Consequently, in this thesis, we have performed extensive simulations for femtocell-macrocell networks setting to investigate the performance of the proposed techniques.