Improved HF modem using convolutional coding

Author

Honary, B. ; Zolghadr, E. ; Darnell, M. ; Maundrell, M.

Author_Institution

Dept. of Eng., Warwick Univ., Coventry, UK

Volume

4

Issue

2

fYear

1992

fDate

4/1/1992 12:00:00 AM

Firstpage

73

Lastpage

82

Abstract

The paper describes the design of a digitally implemented modem for use over HF (2-30 MHz) radio channels. As a completely digital approach offers the prospect of a number of significant improvements, a new digital multifrequency-shift-keying (MFSK) modem has been developed that employs a novel digital processing procedure termed code-assisted bit synchronisation (CABS). Signal detection is achieved via a set of noncoherent correlators, whilst symbol synchronisation and error correction are performed using a soft-decision Viterbi decoder. Practical tests of modem show that it operates effectively under both additive white Gaussian noise and real HF channel conditions

Keywords

digital radio systems; encoding; error correction; frequency shift keying; modems; synchronisation; 2 to 30 MHz; additive white Gaussian noise; code-assisted bit synchronisation; convolutional coding; digital multifrequency-shift-keying; digital radio modem; error correction; noncoherent correlators; real HF channel conditions; signal detection; soft-decision Viterbi decoder; symbol synchronisation;

fLanguage

English

Journal_Title

Electronics & Communication Engineering Journal

Publisher

iet

ISSN

0954-0695

Type

jour

Filename

139156