Iterative equalization with adaptive soft feedback

Author

Gerstacker, Wolfgang H. ; Müller, Ralf R. ; Huber, Johannes B.

Author_Institution

Dept. of Electr. & Electron. Eng., Canterbury Univ., Christchurch, New Zealand

Volume

48

Issue

9

fYear

2000

fDate

9/1/2000 12:00:00 AM

Firstpage

1462

Lastpage

1466

Abstract

In this letter, a novel equalization algorithm applying soft-decision feedback and designed for binary transmission is introduced. In contrast to conventional decision-feedback equalization (DFE), iterations are necessary, because a simple matched filter serves as feedforward filter, which collects signal energy, but creates noncausal intersymbol interference. The rule for generating soft decisions is adapted continuously to the current state of the algorithm. In most cases, standard DFE methods are clearly outperformed. For a class of certain channel impulse responses, performance of maximum-likelihood sequence estimation is attained, in principle. The high performance of the scheme is explained using results from neural network theory

Keywords

adaptive equalisers; feedback; intersymbol interference; iterative methods; matched filters; maximum likelihood sequence estimation; transient response; adaptive soft feedback; binary transmission; channel impulse responses; equalization algorithm; feedforward filter; iterative equalization; maximum-likelihood sequence estimation; neural network theory; noncausal intersymbol interference; performance; signal energy; simple matched filter; soft-decision feedback; Adaptive equalizers; Algorithm design and analysis; Channel estimation; Decision feedback equalizers; Delay estimation; Intersymbol interference; Iterative algorithms; Matched filters; Maximum likelihood estimation; Neural networks;

fLanguage

English

Journal_Title

Communications, IEEE Transactions on

Publisher

ieee

ISSN

0090-6778

Type

jour

DOI

10.1109/26.870012

Filename

870012