EFFICIENT UTILIZATION FOR SPECTRUM HANDOFF IN COGNITIVE RADIO NETWORKS USING OPTIMIZATION TECHNIQUES

Abstract

The growth of wireless communication is advancing rapidly, newlinedemanding attention to spectrum scarcity problem in order to expand mobile newlineservices and high data rates. Since the spectrum may not be fully utilized by newlinethe first priority Primary Users (PU) at all times and in all locations, the newlinespectrum distribution of PU reduced the total utilization of the spectrum by newlineproviding the unused frequency to the second priority Secondary User (SU). newlineThe development of Cognitive Radio Networks (CRN) offers a way to get newlineover these obstacles. It addresses the issue of spectrum inadequacy problem newlinein accessing the PU by means of Dynamic Spectrum Access (DSA). The newlineCRN benefits the SU by enabling it searching for vacant spectrum and newlinerelocate to unused spectrum bands. When a PU requests the spectrum back, a newlinespectrum handoff must be carried out by SU. The kind of policy that will be newlineused for the handoff is decided by the SU. Therefore, the cognitive radio newlinenetwork employs two strategic priorities: spectrum handoff and spectrum newlinesensing to prevent from interference and channel access. newlineLearning through CRN environment, it can sense the spectrum and newlinemake appropriate decision. The spectrum sensing is the specific characteristic newlinefor the channel utilization and channel vacating process based on PU. A newlinefrequent monitoring of PU is progressed for seamless communication in SU. newlineThe spectrum availability is decided based on the range of frequency and newlinearrival rate of PU. Spectrum Handoff plays a significant role in DSA due to a newlinerise in the demand of data transmission.