A QoS based cooperative spectrum utilization in cognitive radio networks

Spectrum sharing is a key problem in cognitive radio networks (CR). After the spectrum sensing and decision processes, detected or predicted spectrum holes need to be utilized by the CR users conforming to specific principles. In this paper, we extended our previously proposed work on a distributed spectrum sharing mechanism by enabling defining service classes among CR users and accomplish spectrum sharing mechanism accordingly. Here, all users sense and decide the channel occupancy by themselves. Cooperation is acquired by a messaging framework and priority mechanisms ensuring fair scheduling among the CR users within the same service class. Messaging topology that represents the deficiencies in Common Control Channel (CCC) is implemented as a random topology. Network model and spectrum sharing system is simulated using MATLAB Simulink environment in terms of Traffic Request Satisfaction Rate, Channel Occupancy Rate and Fairness among CR users. The obtained results are compared with techniques employing rule based channel selection strategies as selfish and random channel selection. Simulation results show that the collaboration and priority mechanism between CR users increases system utility.