Cognitive Multi-Relay Transmission over Asymmetric Fading Channels with Imperfect CSI

  • Nguyen Hong Giang Telecommunications University, Nha Trang, Vietnam
  • Vo Nguyen Quoc Bao Posts and Telecommunications Institute of Technology, Vietnam
  • Hung Nguyen-Le The University of Danang, Vietnam


Outage performance of a cognitive multi-relay system using imperfect channel state information (CSI) of interfering links is formulated in this paper. In the considered cognitive system, it is assumed that wireless channels in the secondary network (source-to-relay and relay-to-destination links) experience Rician fading whereas interfering channels between primary and secondary networks undergo Rayleigh fading. Under the assumption of asymmetric fading, an outage probability (OP) expression of the secondary network is approximately formulated. Analytical OP values are in good agreement with related empirical ones in low signal-to-noise ratio (SNR) regimes. As a result, the approximate OP expression can be used to quantify the effect of asymmetric fading channels and CSI imperfection on the performance of cognitive multi-relay systems in practical SNR ranges.


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How to Cite
GIANG, Nguyen Hong; QUOC BAO, Vo Nguyen; NGUYEN-LE, Hung. Cognitive Multi-Relay Transmission over Asymmetric Fading Channels with Imperfect CSI. Journal of Science and Technology: Issue on Information and Communications Technology, [S.l.], v. 3, n. 1, p. 46-50, mar. 2017. ISSN 1859-1531. Available at: <>. Date accessed: 24 mar. 2023. doi: