Trade off between spectrum cost and quality of service in a cognitive radio network

Abstract

Wireless spectrum is a sporadic resource. For increasing demand of wireless spectrum, requirement of high data rate, innovative servicesrequires an efficient technology for its use.Cognitive Radio (CR) technology is used for solving the stated problems and also for (i) spectrum management (ii) to control the interference behind the distribution of spectrum into various parts. CRs communicate with each other in a network and provide services to its users. CR Network (CRN) is operated by one CRN operator or more than one CRN operators. CRN operators acquire resources from spectrum owner by using (i) spectrum sensing (ii) spectrum leasing to serve its users which incurs cost for CRN operator. In this thesis, an algorithm is developed for CRN operator’s cost minimization while also satisfying the quality of service of its users. There are different algorithms used for this purpose as cost minimization algorithm with fixed power allocation, but work is not done in real time scenario. There are different optimization techniques are used as Stackelberg game theory, Lyapunov optimization technique etc. Proposed novel quality of service based cost minimization algorithm achieves the goals of cost minimization for CRN operator while also satisfying the quality of service of its users. Simulation results show that our proposed algorithm has minimized the total cost for CRN operator and also satisfied the quality of service for secondary users in comparison to existing sensing only and leasing only policy. The results also show improvement in existing algorithm of cost minimization with fixed power allocation.