Open AccessPerformance of Two‐User Two‐Way Amplify‐and‐Forward Relaying Systems with Scheduling
Author(s) -
Fang Zhaoxi,
Li Guosheng,
Li Jun
Publication year - 2011
Publication title -
etri journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.295
H-Index - 46
eISSN - 2233-7326
pISSN - 1225-6463
DOI - 10.4218/etrij.11.0110.0622
Subject(s) - scheduling (production processes) , channel state information , computer science , round robin scheduling , upper and lower bounds , fair share scheduling , wireless , transmission (telecommunications) , bit error rate , channel (broadcasting) , computer network , mathematical optimization , distributed computing , mathematics , telecommunications , quality of service , mathematical analysis
In this paper, we study scheduling schemes for two‐user two‐way wireless relaying systems. Two transmission modes are considered: point‐to‐point direct transmission and two‐way amplify‐and‐forward relaying. An optimal scheduling scheme that opportunistically selects the best transmission mode for each user is proposed to minimize the sum bit error rate (BER). The performance lower bound of the optimal scheduling scheme is analyzed, and closed‐form expression of the lower‐bound BER is derived. However, for optimal scheduling, the scheduler requires the knowledge of channel state information (CSI) of all links. To reduce the feedback information of CSI, we also propose a suboptimal scheduling scheme that selects the transmission mode using only the CSI of two direct links. Simulation results show that there are 4 dB to 8 dB gains for the proposed optimal and suboptimal schemes over the fixed direct transmission and fixed two‐way relayed transmission scheme. The performance gap between the optimal and suboptimal scheduling schemes is small, which implies a good trade‐off between implementation complexity and system performance.