Open AccessUnderlay cognitive relay networks with imperfect channel state information and multiple primary receivers
Author(s) -
Huang Haiyan,
Li Zan,
Si Jiangbo,
Guan Lei
Publication year - 2015
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.2014.0429
Subject(s) - underlay , computer science , interference (communication) , relay , cognitive radio , channel (broadcasting) , computer network , context (archaeology) , channel state information , co channel interference , power control , topology (electrical circuits) , telecommunications , power (physics) , signal to noise ratio (imaging) , wireless , engineering , electrical engineering , physics , paleontology , quantum mechanics , biology
In this study, the authors investigate the effect of imperfect channel state information (CSI) on underlay cognitive radio networks in the presence of multiple primary users (PUs). Particularly, with multiple proactive partial decode‐and‐forward (DF) relays available, both the relay selection channels and interference channels are assumed to be imperfect. In this context, firstly, based on the instantaneous CSI (ICSI) of interference channels, exact closed form expressions for the outage probability (OP) and the interference probability (IP) are derived, where IP is used as a performance metric to quantify the impact of harmful interference caused by secondary user (SU) on PUs. It is shown that, when the ICSI of interference channels are imperfect, the secondary networks always interfere with PUs' communications. Then, to reduce the harmful interference caused by secondary nodes, we propose an adaptive power control scheme relying on the partial CSI (PCSI) of interference channels. Finally, simulation results verify the accuracy and effectiveness of the author's analytical study, and indicate the proposed scheme strikes a good tradeoff between the interference introduced by secondary nodes on PUs and SU's performance.