Simplified designs for AAPP soft decision threshold decoders

Author

Gagnon, F. ; Batani, N. ; Dam, T.Q.

Author_Institution

Dept. of Electr. Eng., Ecole de Technol. Superieure, Montreal, Que., Canada

Volume

43

Issue

38020

fYear

1995

Firstpage

743

Lastpage

750

Abstract

New designs for soft-decision threshold decoders are developed to significantly reduce the complexity and increase the coding gain as compared to previously proposed architectures. The approximate a posteriori probability (AAPP) decoder considered here is a digital approximation of the a posteriori probability (APP) decoder introduced by Massey (1976). These designs are useful for high-rate self-orthogonal convolutional codes with a long constraint length. The study case considered in this paper is for a rate 23/24, constraint length 4056 code used in a typical microwave digital radio. The new decoder architecture provides a four-fold decrease in complexity and an additional 0.3 dB coding gain as compared to previous designs.<>

Keywords

VLSI; convolutional codes; decoding; digital radio; maximum likelihood estimation; microwave links; AAPP decoder; APP decoder; VLSI; a posteriori probability decoder; approximate a posteriori probability; coding gain; complexity reduction; decoder architecture; high-rate codes; long constraint length; microwave digital radio; self-orthogonal convolutional codes; soft decision threshold decoders; Convolutional codes; Decoding; Digital communication; Gain;

fLanguage

English

Journal_Title

Communications, IEEE Transactions on

Publisher

ieee

ISSN

0090-6778

Type

jour

DOI

10.1109/26.380103

Filename

380103