Jamali, V.Michalopoulos, D. S.Uysal, MuratSchober, R.2016-02-162016-02-162015978-146736540-621540217http://hdl.handle.net/10679/2468https://doi.org/10.1109/ISWCS.2015.7454354Due to copyright restrictions, the access to the full text of this article is only available via subscription.In this paper, we propose and analyze a novel q-duplex radio frequency/free space optical (RF/FSO) relaying protocol for a mixed RF and hybrid RF/FSO communication system. In our scheme, several mobile users transmit their data over an RF link to a relay node (e.g. a small cell base station) and the relay forwards the information to a destination (e.g. a macro cell base station) over a hybrid RF/FSO backhaul link. The RF links are full-duplex with respect to the FSO link and half-duplex with respect to each other, i.e., either the user-relay RF link or the relay-destination RF link is active. Depending on the channel statistics, the q-duplex relaying protocol may reduce to full-duplex relaying, when the quality of the FSO link is sufficiently high, or to half-duplex relaying, when the FSO link becomes unavailable due to severe atmospheric conditions. We derive an analytical expression for the end-to-end outage probability of the proposed protocol when the fading for the user-relay RF link, the relay-destination RF link, and the relay-destination FSO link are modelled as Rayleigh, Ricean, and Gamma-Gamma distributed, respectively. Our simulation results confirm the analytical derivations and reveal the effectiveness of the proposed q-duplex protocol and its superiority compared to existing schemes.enginfo:eu-repo/semantics/restrictedAccessConference paper31632000038048090006410.1109/ISWCS.2015.7454354Free-space optical communicationGamma distributionMobile radioOptical linksProtocolsRadio linksRelay networks (telecommunication)Telecommunication network reliability2-s2.0-84984977849