الفهرس 
Objectives of The Thesis
LITERATURE REVIEW ON MULTI-OBJECTIVE OPTIMIZATIONOnly 14 pages are availabe for public view
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Abstract
This thesis investigates the problem of resource allocation available in the Cognitive Radio Network (CRN) operation scenario to the existing users whether they are primary or secondary users. This allocation of resources should be done in a manner such that to optimize the usage of the electromagnetic spectrum. In order to achieve this purpose, we adopted game theoretic approach that fits the scenario of operation and can provide optimized solution. Game theory is the formal study of decision making among multiple decision makers either on a conflict basis or even cooperative basis.
First, we make a brief review on the multi-objective optimization techniques in general. Afterwards, we introduce the basic concepts a CRN along with some of the main definitions and methods of application. We focus in our presentation on the game theory and its different classes applicable in CRNs. We demonstrate as well the main definitions and theorems which shall be used throughout the thesis such as “potential game” and “Stackelberg game”, ... etc.
The thesis, then, focuses on some examples of previous works as well as a study of their simulation results were studied in details and a certain scenario which is the potential and Stackelberg games was chosen to start our development on. As a starting point, simulations of the selected works were conducted using Matlab and compared to the original simulation results to make sure that we are on the right track.
The core part of the thesis focuses on our original contribution in the resource allocation. Firstly, we chose to use continuous power levels for the transmission of the secondary users instead of discrete ones. This modification showed no advantage on the performance of the system and was terminated. Next, a study of the effect of the number of available channels used for transmission throughout the network was conducted and reported as a minor modification.
The major modification, however, was in the updating algorithm used through the transient interval of the system till it reaches equilibrium at no added complexity to the spectrum owners system contrary to previous works which required the licensee of the spectrum to force pricing on the secondary users for using his spectrum. Also, as a second contribution, a modification in the system model has been made in order to adopt the system studied before to work along with a centralized primary system such as Digital Video Broadcasting (DVB) or any other system using a single transmitting base station and multiple receivers.