Analysis of opportunistic access in the spectrum sharing system with heterogeneous secondary users

For the purpose of increasing the utilization efficiency of spectrum, secondary usage method of the licensed spectrum has been explored. In this paper, based on the concept of spectrum pooling, we propose a spectrum sharing system with opportunistic accesses. In order to satisfy with the realistic applications, we define heterogeneous secondary users (non-real-time and real-time services) with different quality-of-service (QoS) requirements in our system model. Since each primary userpsilas requiring channel may be occupied by different types of secondary user, the primary user uses different schemes to solve the collision. Numerical results show that our model can obtain a better tradeoff between increasing the spectrum utilization and guaranteeing the primary userpsilas access priority.