Outage Analysis of Spectrum Sharing Energy Harvesting Cognitive Relays in Nakagami-m Channels

Abstract

Energy harvesting (EH) cognitive relays are an exciting solution to the problem of inefficient use of spectrum while achieving green communications and spatial diversity. In a spectrum sharing scenario, we investigate the performance of a cognitive relay network, where a secondary source communicates with its destination over Nakagami-m channels via decode-and-forward EH relays while maintaining the outage probability of the primary user below a predefined threshold. Specifically, we derive a closed-form expression for the secondary outage probability and show that it is a function of the probability of an EH relay having sufficient energy for relaying, which in turn, depends on the energy harvesting and consumption rates of the EH relay and the primary outage probability threshold. We also show that relaxing the primary outage constraint may not always benefit the cognitive EH relay network due to the limitations imposed on the relay's transmit power by the energy constraint. * The authors are with the

Interference-Assisted Wireless Energy Harvesting in Cognitive Relay Network with Multiple Primary Transceivers

“…Similarly, in cognitive radio, using energy harvesting for energy-limited relays, SUs can achieve significant performance gains [21], [22]. In [22], under spectrum sharing with a PU, an EH relay which forwards the secondary data is considered, while a tradeoff between primary interference constraint and energy constraint due to EH nature of relays is investigated in [23].…”

Interference-Aided Energy Harvesting: Cognitive Relaying With Multiple Primary Transceivers

“…In cognitive radio, using energy harvesting for energylimited relays, authors in [25]- [27] showed that SUs could achieve substantial performance gains without battery recharging or replacement. In [25], authors investigated a trade-off between the primary interference constraint and the energy constraint due to EH nature of relays and found the region of dominance for each of the constraints. The EH model considered in [25] was a generic one and did not assume any specific source of energy.…”

“…In [25], authors investigated a trade-off between the primary interference constraint and the energy constraint due to EH nature of relays and found the region of dominance for each of the constraints. The EH model considered in [25] was a generic one and did not assume any specific source of energy. In [26], authors considered the RF EH model for secondary relays, where relays harvested energy from ST's information signals using a time switching policy.…”

Outage Analysis for SWIPT-Enabled Two-Way Cognitive Cooperative Communications

“…Outage performance in a SWIPT-enabled CCRN under a Nakagami fading channel is analyzed in [9] considering decode-and-forward (DF) relaying. The authors in [10] and [11] investigate the performance of a similar SWIPT-enabled CR network in underlay mode.…”