TITLE:
Design and Analysis of an OSA-BR MAC Protocol for Cognitive Radio Ad Hoc Networks
AUTHORS:
Hassan Al-Mahdi, Mohamed Wahed, Safa Abd El-Aziz
KEYWORDS:
Rendezvous, Cognitive Radio, Ad Hoc, Analytical Model
JOURNAL NAME:
International Journal of Communications, Network and System Sciences,
Vol.7 No.7,
July
25,
2014
ABSTRACT: Cognitive Radio (CR)
is a new communication network paradigm introduced to solve the problems of
spectrum scarcity and inefficient spectrum usage. Basically, it allows the
Secondary Users (SUs) to utilize the Licensed Channels (LCs) of the Primary
Users (PUs) in an opportunistic manner without causing any harmful interference
to the PUs. However, there are many challenges associated with cognitive radio
networks, such as the CR Medium Access Control (CR-MAC) protocols. An important
issue for CR-MAC protocols is to identify whether the spectrum is licensed or
unlicensed. In addition, the sudden appearance of the PU is the most important
feature of the distributed CR-MAC protocols. In this paper, a multichannel
CR-MAC protocol, which reacts efficiently to the appearance of the PUs, is
developed. The proposed protocol is named Opportunistic Spectrum Access with
backup channel and Buffered data with Resume (OSA-BR). The OSA-BR is an unaided
rendezvous, asynchronous, and contention-based MAC protocol. The proposed
protocol operates in heterogeneous environment, where the SUs utilize both LCs
and unlicensed channel (ULs) and the activities of the Classical Users (CUs)
are taken into consideration. In addition, the concept of the backup channel
and the buffer with resume are introduced. The simulation results show that
OSA-BR accomplishes 35% throughput gain over the SWITCH protocol and 55% over
other CR-MAC protocols.