Open AccessOptimising energy efficiency of LDPC coded chase combining HARQ system
Author(s) -
Wu Yue,
Yang Hongwen
Publication year - 2015
Publication title -
electronics letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.375
H-Index - 146
eISSN - 1350-911X
pISSN - 0013-5194
DOI - 10.1049/el.2014.4462
Subject(s) - retransmission , low density parity check code , additive white gaussian noise , hybrid automatic repeat request , computer science , efficient energy use , transmission (telecommunications) , energy (signal processing) , algorithm , signal to noise ratio (imaging) , electrical efficiency , coding gain , electronic engineering , channel (broadcasting) , power (physics) , decoding methods , mathematics , telecommunications , statistics , engineering , physics , electrical engineering , quantum mechanics
The energy efficiency of the low‐density parity check (LDPC) coded chase combining hybrid automatic repeat request (HARQ) system over the additive white Gaussian noise channel is analysed. The energy efficiency can be improved by increasing the maximum transmission number ( K ) and reducing the transmit power. The asymptotic energy efficiency corresponding to K = ∞ equals the reciprocal of the threshold signal‐to‐noise ratio of the forward error correction code, which does not depend on the falling speed of the word error ratio. When the retransmission number is relatively small, optimising equal transmit power and variable transmit power can improve the energy efficiency by up to 10 and 18% respectively, compared with minimum equal power transmission.