Abstract

Due to the effective utilization rate of the radio frequency spectrum, Cognitive Radio Network (CRN) has gained more popularity in the current research field. The spectrum sensing techniques detect the presence of the idle channel and reallocate to the Secondary Users (SUs). However, the existing spectrum sensing and channel estimation approaches incurs delay while searching for the new channels. To reduce the delay and achieve optimal selection of the channel in CRN, this paper proposes a Hidden Markov Model (HMM)-based channel selection framework. The Time-Slot based optimal routing mechanism is introduced to minimize the delay occurred during the channel search and optimize the range of the spectrum band. Therefore, the bandwidth range of the node is estimated, and the channel is allocated to the SU. The proposed framework exhibit better end-to-end throughput, bandwidth-power product and lower running time, energy consumption, and average end-to-end delay when compared to the existing schemes.

Introduction

CRN [1] solves the radio spectrum scarcity problems and maximizing the spectrum utilization efficiency. The Cognitive Radio (CR) is considered as a vital technology for the next generation that offers the capability for the efficient utilization of the spectrum. CRN is a collection of the primary and secondary networks. The main benefit of the CRs is to reduce the exploitation of the unused spectrum resources by using the characteristics of reconfigurability and intelligent sensing. Instead of the spectrum resources, the channel K-factor and bandwidth are considered as the additional communication parameters [2,3]. The cognitive approach is to permit the coexistence of various networks on the same transmission resources. In the overlay approach, it is ensured that the SUs do not produce any detrimental interference to the Primary Users (PUs). The CR system is based on the sensing and reconfigurability characteristics to fulfill the above requirements. The users can either interconnect with each other in a multi-hop manner or contact the Base Station (BS).