الفهرس 
AbstractOnly 14 pages are availabe for public view
 |  | from | 107 |  |  |
| | | from | 107 | | |
Abstract
Cognitive radio technology introduces a perfect solution to cope with an inefficient spectrum specification problem. This leads to an essential need to develop a new form of medium access control protocol or modify the classical medium access control protocol found in literature in order to enable the cognitive radio networks to achieve their goals. This new form is called cognitive medium access control protocols (CR-MACs). Hence, CR-MAC is a hot spot area which has a variety of aspects to search and study.
In this thesis, we focus on CR-MAC protocols. We evaluate the performance of different categories of CR-MAC protocols. The thesis is divided into two main parts; a theoretical part and a simulation model.
In the theoretical part, a comprehensive description of complete picture for CR-MAC design is introduced. A comparison of fifty CR-MACs is shown. Then, a classification of CR-MAC protocols is introduced.
In the simulation model, the performance evaluation of different CR-MACs protocols is given using NS2 simulator. A simulation system is basically based on the recognition of primary users’ appearance with increasing a packet size. The performance of two different CR-MAC protocols are evaluated; a special case of blind cognitive MAC protocols and a special case of cognitive MAC protocol using statistical channel allocation for wireless ad-hoc networks protocol.
The simulation results prove that the first protocol outperforms the second protocol in all performance metric such as throughput and packet delivery ratio and received packet.