Title
Green Cognitive Relaying: Opportunistically Switching Between Data Transmission and Energy Harvesting
Abstract
Energy efficiency has become an encouragement, and more than this, a requisite for the design of the next-generation wireless communication standards. In this paper, a dual-hop cognitive (secondary) relaying system is considered, incorporating multiple amplify-and-forward relays, a rather cost-effective solution. First, the secondary relays sense the wireless channel, scanning for a primary network activity, and then convey their reports to a secondary base station (SBS). Afterward, the SBS, based on these reports and its own estimation, decides cooperatively the presence of primary transmission or not. In the former scenario, all the secondary nodes start to harvest energy from the transmission of primary nodes. In the latter scenario, the system initiates secondary communication via a best relay selection policy. Performance evaluation of this system is thoroughly investigated, by assuming realistic channel conditions, i.e., non-identical link distances, Rayleigh fading, and outdated channel estimation. The detection and outage probabilities as well as the average harvested energy are derived as new closed-form expressions. In addition, an energy-efficiency optimization problem is analytically formulated and solved, while a necessary condition in terms of power consumption minimization for each secondary node is presented. From a green communication standpoint, it turns out that energy harvesting greatly enhances the resources of secondary nodes, especially when primary activity is densely present.
Year
DOI
Venue
2015
10.1109/JSAC.2016.2611841
IEEE Journal on Selected Areas in Communications
Keywords
Field
DocType
Sensors,Relays,Energy harvesting,Wireless communication,Data communication,Wireless sensor networks,Optimization,Green communications,Energy efficiency
Base station,Wireless,Rayleigh fading,Data transmission,Efficient energy use,Energy harvesting,Computer network,Communication channel,Mathematics,Relay
Journal
Volume
Issue
ISSN
abs/1507.06396
12
0733-8716
Citations 
PageRank 
References 
4
0.40
37
Authors
4
Name
Order
Citations
PageRank
Nikolaos I. Miridakis115118.40
Theodoros A. Tsiftsis21406116.77
George C. Alexandropoulos375945.84
Mérouane Debbah48575477.64