SAGRA: A Spectrum Aware Geographic Routing Algorithm Proposal for Multihop Cognitive Radio Networks

Abstract

In the recent years Cognitive Radio (CR) technology imposed itself like a very good solution to the increasing
spectrum utilization. This technology recommends the development of a new radio type – a cognitive radio – endowed
with intelligence that shall sense, share, and use the spectrum opportunities (SOP) of the preexisting wireless networks,
that is the channels that are not used by the licensed users.A new routing algorithm for CR networks (CRN): SAGRA –
Spectrum Aware Geographic based Routing Protocol is presented in the paper. As suggested by the name, the
geographic, and the spectrum aware routing concepts were used together in the protocol’s design. The dynamism and
flexibility, characteristic to both CR and IP networks, made us compare the CR concept with the IP concept (a wireless
versus wired flexible environment comparison); thus we assumed the IP routing approach for CRN. The proposed
strategy is based on hop-by-hop routing, local decisions being taken by nodes according to both local information (CR
node’s neighborhood) and global information (the entire topology of CRN), channels availability, and destination
location.