الفهرس 
COGNITIVE RADIO (CR) AND MASSIVE MIMO (M-MIMO)
Energy EfficiencyOnly 14 pages are availabe for public view
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Abstract
It became obvious that the current available technologies and techniques used in different communication systems would not be sufficient to withstand the huge expansion of the needed data rates in the next few years. This increased the need to devise new technologies that can increase the data rates while using the same available resources.
Two of the most promising technologies are Cognitive Radio (CR) systems & Massive MIMO (Multiple-Input-Multiple-Output). The former one solves the scarcity in the available spectrum by sharing it among different users and making use of the unused spectrum to increases the utilization of the available spectrum. The latter one provides great opportunities in the area of increasing the available date rates and decreasing interference between the users by using precoding.
The current researches have presented the idea of integrating different state-of-the-art technologies to improve the system performance.
This thesis studies the enhancement that could be achieved by using massive MIMO in CR systems. Two different precoder designs for massive MIMO systems are proposed to be used in both the Underlay and Overlay CR scenarios. The proposed designs are used with low computational time algorithms to maximize the sum rate achieved by the system while decreasing the computational complexity of the system. The performance of the proposed precoders is studied using both uncorrelated and correlated channel models.