Since the wireless spectrum is limited, the use of licensed channels for secondary purposes is seen as an important solution to the spectrum scarcity problem. The objective of the work presented in this paper is to model, develop and analyze a cognitive radio network in which secondary users (SUs) utilize opportunistically available spectrum holes of the primary network. In the proposed network model, it is assumed that primary users (PUs) are licensed users and have a higher priority in access to the channel than secondary users and thereby are unaffected by the SUs’ channel utilization. PUs employ Time Division Multiple Access as a channel access mechanism and secondary users use the time slots unoccupied by the PUs. Three slot allocation strategies for Cognitive Radio (CR) networks: non-slot-handoff strategy, slot-handoff strategy, and slot-reservation strategy are developed, modeled, and simulated by using Riverbed Modeler simulation software. Moreover, channel access performances of these three strategies in terms of call block, call drop and call handoff probabilities are analyzed. According to the extensive simulation results, the non-slot-handoff strategy gives the lowest call block probability while the slot-reservation strategy provides the lowest call drop probability. When the SUs’ offered load is 0.05, the slot-reservation strategy gives 1.75 times better call drop probability results than those of the slot-handoff strategy. However, for the same offered load, the non-slot-handoff strategy gives 2.26 times better call block probability results compared to the slot-reservation strategy.
Primary Language | English |
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Subjects | Electrical Engineering (Other) |
Journal Section | Articles |
Authors | |
Publication Date | July 31, 2024 |
Published in Issue | Year 2024 Volume: 12 Issue: 3 |