Open AccessImproving capacity for physical network coding with lattice strategies in two‐way fading channels
Author(s) -
Zhan Ao,
Wu Chengyu,
Shi Qingjiang,
Xu Weiqiang
Publication year - 2017
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.2016.1262
Subject(s) - fading , codebook , relay , lattice (music) , modulo , computer science , algorithm , topology (electrical circuits) , coding gain , channel (broadcasting) , mathematics , telecommunications , decoding methods , power (physics) , discrete mathematics , combinatorics , physics , quantum mechanics , acoustics
In this study, the capacity problem in a two‐way fading channel is considered. The authors propose amplify‐and‐forward with lattice codes (AF&LC), exploiting a modulo operation at the relay. Without destroying the construct of codebook, the modulo operation reduces the power of the received signals, and thus achieves a larger power‐scaled gain than the amplified‐and‐forward with random codes (AF&RC). It is proved that AF&LC outperforms AF&RC in the high signal‐to‐noise ratio (SNR) regime by employing theoretical analyses. By simulating one‐dimension lattice codes, AF&LC achieves about 1.5 dB SNR gain over AF&RC with error probability 10 −2 . Compared with decode‐and‐forward with lattice codes (DF&LC) and fixed modulo‐and‐forward (FMF), AF&LC achieves larger rate region which is closer to upper bound in some scenarios. Moreover, AF&LC can work in fading two‐way channels without feedback schemes, which is easier to be implemented than DF&LC, FMF and compress‐and‐forward.