Novel Cooperative Schemes on Spectrum Sensing in Multi-Primary-User Cognitive Radio Network

It is widely accepted that the emergence of cognitive radio (CR) will lead to a wireless communication revolution. Spectrum sensing is one key process of CR, which makes effective use of scarce spectrum. Two novel schemes, clustering and locating schemes, are presented for spectrum sensing based on energy detection on the condition that there are multiple primary users in the cognitive radio network. Clustering scheme is used for estimating the number of primary users and dividing the secondary users into several groups based on their geographical position as well as received energy by my proposed iterative max-min theory, and then locates the position of primary user by locating scheme based on the center of gravity algorithm. These schemes work well when only geographic information and the amount of energy can be obtained. Finally, numerical analysis and simulation results of these schemes are provided. It is proved that the proposed criteria are practical and efficient in the absence of the type of primary signal and the amount of noise which are necessary for previous methods.