A Novel Centralized Spectrum Allocation Scheme in Cognitive Radio Networks and Performance Evaluation
In cognitive radio networks, in order to improve the spectrum utility, secondary users are allowed to opportunistically access the spectrum unused by the primary users. There are two categories of spectrum allocation schemes, i.e., distributed spectrum allocation scheme and centralized spectrum allocation scheme. In a centralized spectrum allocation scheme, a central scheduler coordinates and manages the assignment of the spectrum unused by the primary users. Letting primary users and secondary users operate in a synchronized way, considering that the transmissions of secondary users may be interrupted by primary users, a slotted centralized spectrum allocation scheme with transmission interruption is proposed in this paper.