Routing Protocols For Cognitive Radio Ad Hoc Networks

Cognitive radio ad hoc networks (CRAHNs) determine an available solution to resolvethe current problems of ineffective in the spectrum allocation, and to implement highlyapprovingly and self-organizing wireless networks. Cognitive radio (CR) equipments arefigured to use the spectrum in an opportunist way by actively accessing different licensedparts of the spectrum. To this purpose, most of the current study has mainly concentratedon inventing spectrum sensing and sharing technique at the link layer, so that with thetransmissions of other licensed users, CR equipments can work without interfering, alsocalled primary users (PUs). However, there is also solid to deliberate the influence of suchstrategy on the higher layers of the protocol stack, to which provides effective end-to-enddata delivery.The former routing protocol in traditional ad hoc network is not suitable for theCRAHNs because of the interference from the primary systems, so that routing in theCRAHNs has some challenges to resolve. Until now, routing layer protocols form asubstantial yet not deeply investigated field of research over CRAHNs. In this thesis,routing technique for ad-hoc cognitive networks will be mentioned. These methodssupport multi-band communication networks under the varied interference from theprimary systems.First, the overview of the CRAHNs will be researched. It will show how this networkoperates, and how the spectrum-aware operations are necessary in this network. Thearchitecture of the CRAHNs will be mentioned in this part.Second, some routing protocols in CRAHNs will be given to resolve some problemsand increase throughput. This part will mention how the routing protocols work in thisnetwork. Some routing algorithms are recommended. Routing algorithms in this part willshow the better performance when compare with former routing protocols in thetraditional ad hoc network. The routing protocols in CRAHNs will be classified in thispart.Third, we use NS2to simulate the routing in the CRAHNs. We use the NS2to builtMAC protocol model, Cognitive radio routing model for CRAHNs. NS2is the opensource, it uses for simulate in case single radio, multi channel in this thesis. The results ofthe simulation will demonstrate that the throughput will increase when compare withAODV routing protocol. It also demonstrates that when we increase the number ofchannel, the throughput will increase, and the collision also will decrease.