الفهرس 
Chapter 1:- IntroductionOnly 14 pages are availabe for public view
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Abstract
The mMIMO can be considered as a powerful tool toward the 5G networks.
However, there is no satisfied performance for users under shadowing. In order to
provide a good service for shadowed users and indoor ones, there should be distributed
APs over the cell coverage. This distribution refers to the so called cell-Free mMIMO.
By this technology, there is a ubiquitous coverage for users inside a cell.
The intelligent reflecting surfaces “IRSs” are special types of cooperative
communication. Unlike relays, the IRSs can provide directivity of signal or nulling
signal in a direction without noise amplification. The cooperative communication can
enhance the performance of a cell-Free mMIMO system. It can let the system have a
ubiquitous coverage. Moreover, it can let the system have more greenness.
In this thesis, the cell-Free mMIMO system performance is enhanced by
deployment of intelligent reflecting surfaces “IRSs”. The IRSs can increase the system
performance. The cognitive radio technology is a powerful interference mitigation
tool. This technology can mitigate the interference in wireless systems. By adaption
of cognitive radio technology and IRSs, the cell-Free mMIMO performance can be
greatly increased.
The cognitive IRSs are implemented in cell-Free mMIMO system in order to
provide good and ubiquitous coverage with satisfied performance for users. The cellFree mMIMO, based on IRSs and cognitive IRSs, is mathematically modeled. The
required mathematical equations are derived. The system is simulated.
The simulation results display that implementation of IRSs or cognitive IRSs, in
a cell-Free mMIMO, can greatly increase the spectral efficiency “SE” and energy
efficiency “EE”.