13844

12582

كارشناسي ارشد

مخابرات

اصفهان: دانشگاه صنعتي اصفهان، دانشكده برق و كامپيوتر

۱۳۹۷

يازده، ۹۰ص.: مصور، جدول، نمودار

مهدي مهدوي

علي محمد دوست حسيني، محمد صادق فاضل

1397/06/25

كتابنامه

برق و كامپيوتر

مهندسي برق و كامپيوتر

ID12582

Resource Allocation and Relay Selection in a Cognitive Radio Network with Cooperation Among Primary and Secondary Users Alireza Sanefar a sanefar@ec iut ac ir Date of Submission May 12 2018 Isfahan University of Technology Department of Electrical and Computer Engineering Degree M Sc Language Farsi Supervisor Mehdi Mahdavi m mahdavi@cc iut ac irAbstract The concept of cognitive radio networks has been raised in order to improve efficiency in using thespectrum For this purpose the dynamic spectrum allocation is performed among unlicensed users Cooperative communication is considered as an effective way to deal with the effects of channel fadingand increase network coverage In cooperative communication one or more intermediate nodes whichare known as relay help the source node to send information Even though cooperative communicationhas advantages such as reducing bit error rates reducing outage probability etc like othercommunication systems experiences some limitations such as power consumption bandwidth andmaximum data rate The features of cognitive radio networks and cooperative communication have ledresearchers to use both technologies together Different types of cooperative cognitive radio networkscan be considered in which cooperation will exist in spectrum sensing or in transmitting information In recent years the idea of green communication has made energy efficiency to be considered as animportant criterion in communications networks For this purpose in this thesis the problem of optimalresource allocation considering energy efficiency for a cooperative cognitive radio network has beeninvestigated Here the proposed cooperative cognitive radio network consists of a primary source aprimary destination and a number of secondary users in which secondary users use the underlay modeto transmit their data Using the proposed relay selection criteria the primary source chooses a relayfrom the secondary users to cooperate with primary transmissions Here the allocation of resources isbased on the energy efficiency of the selected relay and is formulated in the form of a constraintoptimization problem To solve such a problem a search based heuristic algorithm is proposed Finally numerical implementation of the proposed network with the proposed relay selection and resourceallocation algorithm is performed and results of selected relay energy efficiency secondary networkenergy efficiency and secondary network lifetime are studied and compared with some existingmethods Finally the proposed network is simulated without considering any theoretical assumptionand the simulation results are studied along with those from numerical implementation keywords Cognitive radio network Cooperative communication Energy efficiency Resourceallocation

مهدي مهدوي

علي محمد دوست حسيني، محمد صادق فاضل