GPS-Assisted Spectrum Allocation for Cognitive Radio Networks with Femtocells

In this paper, a novel GPS-assisted scheme to reduce operation costs of cognitive radio networks with femtocells is proposed. In this scheme, the secondary user (SU) network, represented by the cognitive base station (CBS), determines the minimum number of channels needed for its operation before it starts purchasing spectrum from primary user (PU) networks. This is achieved by grouping the femtocell secondary users (FSU´s) based on the distances between them. Simulations show that grouping the femtocells will result in a reduction in the number of channels to be purchased and will consequently cut the operation cost of the SU network.