Analysis of Spectrum Handoff under Diverse Mobile Traffic Distribution Model in Cognitive Radio

Abstract

The static frequency allocation in wireless communication became a major issue for an efficient spectrum utilization. Also some of the frequency channels are not fully utilized because of spatial and temporal variations. Hence the focus of the new spectrum management policies is dynamic spectrum access (DSA) technology based on cognitive radio (CR). Spectrum mobility is considered to be the next big challenge in CR technology. Spectrum mobility is associated with spectrum handoff and thus the later is the new research challenge to be addressed. In this paper, we analyze the probability of spectrum handoff under diverse realistic primary user and secondary user traffic models. We consider the distribution of CR user call duration and residual time of spectrum holes as parameters to establish a standard form of probability of handoff. We analyze different distribution models for the residual time under zero switching delay and finite switching delay conditions. The relationship of probability of spectrum handoff w.r.t CR calls duration time and availability of spectrum holes are derived. We also consider the switching delay between spectrum handoffs for a more realistic environment and analyzed all the related parameters. The simulation result shows that the Erlang-3 distribution under both the cases offers better performance with minimum probability of spectrum handoff.