Capacity analysis of OFDM / FBMC based Cognitive Radio networks with estimated CSI

In this paper, we focus on the channel capacity analysis of a Cognitive Radio (CR) network using two types of multicarrier communications: conventional Orthogonal Frequency Division Multiplexing (OFDM) with Cyclic Prefix (CP) and Filter Bank based Multi-Carrier (FBMC) modulations. We use a resource allocation algorithm in which subcarrier assignment and power allocation are carried out sequentially. By taking the impact of Inter-Cell Interference (ICI) resulting from timing offset into account, the maximization of total information rates is formulated, subject to maximum power constraint as well as interference constraint from Secondary User (SU) to Primary User (PU). Since the channel gain information between SU and PU can´t be precisely estimated, the amount of the interference induced by SU to PU is calculated on the basis of an estimated Channel State Information (CSI), which is determined by a prescribed outage probability of primary systems. Simulation results show that FBMC can achieve higher channel capacity than OFDM, which indicates that FBMC is a potential candidate for physical layer data communication in CR context.