Paper Info
Title
A Factor Graph Approach to Joint OFDM Channel Estimation and Decoding in Impulsive Noise Environments
Abstract
We propose a novel receiver for orthogonal frequency division multiplexing (OFDM) transmissions in impulsive noise environments. Impulsive noise arises in many modern wireless and wireline communication systems, such as Wi-Fi and powerline communications, due to uncoordinated interference that is much stronger than thermal noise. We first show that the bit-error-rate optimal receiver jointly estimates the propagation channel coefficients, the noise impulses, the finite-alphabet symbols, and the unknown bits. We then propose a near-optimal yet computationally tractable approach to this joint estimation problem using loopy belief propagation. In particular, we merge the recently proposed “generalized approximate message passing” (GAMP) algorithm with the forward-backward algorithm and soft-input soft-output decoding using a “turbo” approach. Numerical results indicate that the proposed receiver drastically outperforms existing receivers under impulsive noise and comes within 1 dB of the matched-filter bound. Meanwhile, with $N$ tones, the proposed factor-graph-based receiver has only $O(N\\log N)$ complexity, and it can be parallelized.
Year
DOI
Venue
2014
10.1109/TSP.2013.2295063
Signal Processing, IEEE Transactions  
Keywords
Field
DocType
OFDM modulation,channel estimation,error statistics,graph theory,impulse noise,message passing,turbo codes,GAMP algorithm,OFDM channel estimation,Wi-Fi communications,bit-error-rate optimal receiver,factor graph approach,finite-alphabet symbols,forward-backward algorithm,generalized approximate message passing algorithm,impulsive noise environments,joint estimation problem,near-optimal yet computationally tractable approach,orthogonal frequency division multiplexing transmissions,powerline communications,propagation channel coefficients,soft-input soft-output decoding,thermal noise,turbo approach,wireless communication systems,wireline communication systems,OFDM,factor-graphs,generalized approximate message passing (GAMP),impulsive noise,iterative receivers,sum-product algorithm,uncoordinated interference
Factor graph,Computer science,Control theory,Turbo code,Noise (electronics),Communications system,Algorithm,Theoretical computer science,Impulse noise,Decoding methods,Orthogonal frequency-division multiplexing,Belief propagation
Journal
Volume
Issue
ISSN
62
6
1053-587X
Citations 
PageRank 
References 
27
1.01
24
Authors
3
Name
Order
Citations
PageRank
Marcel Nassar126020.34
Philip Schniter2162093.74
B. L. Evans32819228.43