Open AccessErgodic and outage capacities of relaying channels in spectrum‐sharing constrained systems
Author(s) -
Ben Fredj Kaïs,
Aïssa Sonia,
Musavian Leila
Publication year - 2013
Publication title -
iet communications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.355
H-Index - 62
eISSN - 1751-8636
pISSN - 1751-8628
DOI - 10.1049/iet-com.2011.0006
Subject(s) - transmitter , relay , fading , rayleigh fading , computer science , nakagami distribution , transmitter power output , ergodic theory , node (physics) , topology (electrical circuits) , transmission (telecommunications) , interference (communication) , channel (broadcasting) , computer network , relay channel , telecommunications , power (physics) , mathematics , physics , mathematical analysis , quantum mechanics , combinatorics
This study investigates the capacity of multiple relay channels in different fading and shadowing environments under spectrum‐sharing constraints. The authors consider that a secondary user (SU) is allowed to share the spectrum band with a primary user (PU) provided that the SU's transmit power remains below an interference power threshold set by the PU. Considering a scenario where the SU's transmitter and receiver cannot communicate directly, a relay node, chosen among a set of K terminals, helps transmitting data from the SU's transmitter to the destination. The SU's transmitter and chosen relay node adapt their corresponding transmission parameters so as to satisfy the interference‐power constraint at the PU's receiver. The authors derive closed‐form expressions for the ergodic capacity of the SU's channel in Rayleigh fading, Nakagami‐ m fading and lognormal shadowing environments. They further obtain the outage capacity assuming the aforementioned environments and the above‐mentioned spectrum‐sharing limitations. Numerical results are provided to reinforce our theoretical derivations.