Voice Service Support over Cognitive Radio Networks

In this paper, quality of service (QoS) provisioning for voice service over cognitive radio networks is considered. As voice traffic is sensitive to delay, the presence of primary users and the requirement that secondary users should not interfere with them pose many challenges for QoS support for secondary voice users. Two cognitive medium access schemes are proposed in this paper for the secondary voice users to access the available channel. An analytical model is developed to obtain the voice service capacity (i.e., the maximum number of voice users that can be supported with QoS guarantee) for the secondary users, taking the impact of primary users' activities into consideration. The analytical model is validated by the simulation. The analytical results will be useful to support voice service in cognitive radio networks.