Adaptive channels' selection for hierarchical cluster based cognitive radio networks

Cognitive Radio (CR) usually performs an analysis of the existing environment, enabling collection of all information on current spectrum use and available resources, to decide on its own transmission parameters to optimize communication performance. From practical point of view, the principal task of spectrum sensing is an efficient detection of different types of signals. This paper presents behavior of Sensing Client (SC) as a logical block of Supervisor (SP) in CR node, to obtain information about backup channels' ranking list. Methodology of creation, refreshing the ranking list of backup channels and change of used channel by SP are the main goals of this research. The ranking list of backup channels is based on spectrum sensing results collected by all nodes according to predefined sensing policy, enabling different sensing schemes like detector type, number of slots for sensing, sensing period etc. Channels with the highest positions on the ranking list are potential backup channels, used in case of jamming, interferences from legacy systems, decreasing link quality caused by nodes positions changes etc. To analyze behavior of SC, several simulation scenarios were developed. All tests were performed for CR network topology with presence of jammers and interferences from other users. Presented results are based on CORASMA simulator.