Abstract:
Spectrum scarcity is one of the major problems affecting the advancement of wireless
technology. The world is now entering into a new era called the “Fourth Industrial
Revolution” and technologies like the Internet of Things (IoT) and blockchain are surfacing
at a rapid pace. All these technologies and this new era need high speed network
(Internet) connectivity. Internet connectivity is reliant on the availability of spectrum
Channels. The Federal Communication Commission (FCC) has emphatically alluded on
the urgency of finding quick and effective solutions to the problem of spectrum scarcity
because the available spectrum bands are getting depleted at an alarming rate.
Cognitive Radio Ad Hoc Networks (CRAHNs) have been introduced to solve the problem
of spectrum depletion. CRAHNs are mobile networks which allow for two groups of users:
Primary Users (PUs) and Secondary Users (SUs). PUs are the licensed users of the
spectrum and SUs are the unlicensed users. The SUs access spectrum bands
opportunistically by switching between unused spectrum bands. The current licensed
users do not fully utilize their spectrum bands. Some licensed users only use their
spectrum bands for short time periods and their bands are left idling for the greater part
of time. CRNs take advantage of the periods when spectrum bands are not fully utilized
by introducing secondary users to switch between the idle spectrum bands. The CRAHNs
technology can be implemented in different types of routing environments including
military networks. The military version of CRAHNs is called Military Cognitive Radio Ad
Hoc Networks (MCRAHNs). Military networks are more complex than ordinary networks
because they are subject to random attacks and possible destruction.
This research project investigates the delays experienced in routing packets for
MCRAHNs and proposes a new routing algorithm called Spectrum-Aware Transitive
Multicasting On Demand Distance Vector (SAT-MAODV) which has been optimized for
reducing delays in packet transmission and increasing throughput. In the data
transmission process, there are several levels where delays are experienced. Our
research project focuses on Routing Path (RP) delay, Spectrum Mobility (SM) delay and
Node Relay (NR) delay. This research project proposes techniques for spectrum
switching and routing called Time-Based Availability (TBA), Informed Centralized Multicasting (ICM), Node Roaming Area (NRA) and Energy Smart Transitivity (EST). All
these techniques have been integrated into SAT-MAODV. SAT-MAODV was simulated
and compared with the best performing algorithms in MCRHANs. The results show that
SAT-MAODV performs better than its counterparts
