Paper Info
Title
Ergodic Capacity Comparison of Different Relay Precoding Schemes in Dual-Hop AF Systems With Co-Channel Interference
Abstract
In this paper, we analyze the ergodic capacity of a dual-hop amplify-and-forward relaying system, where the relay is equipped with multiple antennas and subject to co-channel interference and the additive white Gaussian noise. Specifically, we consider three heuristic precoding schemes, where the relay first applies the: 1) maximal-ratio combining (MRC); 2) zero-forcing (ZF); and 3) minimum mean-squared error (MMSE) principle to combine the signal from the source, and then steers the transformed signal toward the destination with the maximum ratio transmission (MRT) technique. For the MRC/MRT and MMSE/MRT schemes, we present new tight analytical upper and lower bounds for the ergodic capacity, while for the ZF/MRT scheme, we derive a new exact analytical ergodic capacity expression. Moreover, we make a comparison among all three schemes, and our results reveal that, in terms of the ergodic capacity performance, the MMSE/MRT scheme always has the best performance and the ZF/MRT scheme is slightly inferior, while the MRC/MRT scheme is always the worst one. Finally, the asymptotic behavior of ergodic capacity for the three proposed schemes are characterized in large N scenario, where N is the number of relay antennas. Our results reveal that, in the large N regime, both the ZF/MRT and MMSE/MRT schemes have perfect interference cancellation capability, which is not possible with the MRC/MRT scheme.
Year
DOI
Venue
2014
10.1109/TCOMM.2014.2329492
Communications, IEEE Transactions  
Keywords
DocType
Volume
Amplify-and-forward systems,Spread spectrum communication,Encoding
Journal
62
Issue
ISSN
Citations 
7
0090-6778
32
PageRank 
References 
Authors
1.02
31
6
Name
Order
Citations
PageRank
Guangxu Zhu134324.03
Caijun Zhong22007120.77
Himal A. Suraweera32639117.31
Z. Zhang42308198.54
Chau Yuen54493263.28
Rui Yin612911.38