Paper Info
Title
Coding Performance For Signal Dependent Channels In Visible Light Communication System
Abstract
Avalanche photo-diodes (APD) are widely employed in visible light communication (VLC) systems. Experiments show that under official illuminance APD shot noise can not be ignored due to the multiplication process. Under VLC dual-purpose illumination, symbols on different constellation points inevitably experience different levels of noise. In such a signal dependent noise channel, traditional log likely-hood ratio (LLR) calculation for decoder assuming signal independent noise will cause performance loss. In this work, we first investigate the general signal dependent Gaussian channel. The optimal LLR calculation for decoder is then derived. We further analyze the extrinsic information transfer chat to find the decoding thresholds. Finally a modified minimum sum algorithm is suggested with reduced complexity. Numerical simulations show that, with a regular (3,6) low-density parity check (LDPC) code of block length 20000, our proposed scheme can achieve 0.7dB gain over the scheme designed for signal independent noise.
Year
Venue
Keywords
2015
2015 IEEE GLOBAL CONFERENCE ON SIGNAL AND INFORMATION PROCESSING (GLOBALSIP)
VLC, APD, shot noise, LDPC code
Field
DocType
Citations 
Parity bit,Low-density parity-check code,Communication channel,Algorithm,Theoretical computer science,Modulation,Visible light communication,Decoding methods,Shot noise,Signal transfer function,Mathematics
Conference
0
PageRank 
References 
Authors
0.34
5
6
Name
Order
Citations
PageRank
Ming Yuan100.34
Xiaoshi Sha200.34
Xiao Liang34410.89
Ming Jiang419831.08
Jiaheng Wang577151.96
Chunming Zhao667164.30