Routing Techniques In Cognitive Radio Networks: A Survey

Abstract

Cognitive Radio Networks (CRNs)

Techniques for extending unicast CR networks to multi‐source multi‐destination over Rayleigh fading channels

“…reactive, proactive, multi‐cast and hierarchical protocols that are available for such type of networks. Thus, the focus is now on evaluating the novel routing protocols for CRNs, since routing is regarded to be a difficult task for such type of networks, especially in multi‐hop CRNs because of varying channel availability as well as data rates [13]. A brief overview pertaining to the research with regards to routing for CRNs has identified two distinct key categories: approaches that build on full spectrum knowledge, and approaches that only regard the local spectrum knowledge gained via distributed procedures as well as protocols, as given in [14].…”

Overview and Literature Survey on Routing Protocols for Mobile Cognitive Radio Ad Hoc Networks

“…The Classification of Mobile Cognitive radio Ad hoc networks [4] is of two types, which is described in the following Figure 1.…”

“…In CR ad hoc networks, a node may not be able to transmit immediately if it detects the presence of a Primary user on the spectrum. [6] In MCRANs, unidirectional links are more possible [4]. Such links will be available for a fraction of time instead of minutes or hours.…”

“…Thus these networks use the licensed band in opportunistic manner for communication. These communication opportunities are available when primary users have fewer usage of their frequency band or they are not using it at all [4]. Hence availability of channel is time and geographic based.…”

A Routing Algorithm based on Semi-supervised Learning for Cognitive Radio Sensor Networks

“…Cognitive Radio Sensor Devices (CRSDs), which are also referred to as secondary users, share the licensed band with primary users (PUs) who have higher priorities in occupying the bands in a non-interfered manner. This indicates that the topology of CRSN is changing un-predictably due to PUs' activities and causes considerable difficulty in guaranteeing stable and efficient communications (Cesana et al, 2011;Akan et al, 2009;Ali et al, 2011).…”