Real-Time Recognition of Manual Morse Telegraphy Using Nonlinear Estimation and Viterbi Decoding.

Abstract

This report describes the analysis and design of a sophisticated real-time detector and decoder for manually-sent Morse code signals transmitted via high-frequency radio circuits. The system software is designed to run if required in a distributed computer network such as the DCN and can provide simultaneous multicircuit decoding capabilities, using a multiplexed analog-digital converter and multiple terminals, in a single machine. The system uses the principles of optimum filtering and receiver design, including matched filtering and Viterbi decoding. The statistical structure of the Morse process is encapsulated in a Markov model which includes a-priori probabilities and transition probabilities reflecting the entire alphabetical structure of the code. A key component in the design is a new algorithm, called ratio-weighted estimation (RWE) which provides extremely fast adaptation to the time-varying Morse code parameters typical of multioperator circuits.

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Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1977
Accession Number
ADA051001

Entities

People

  • David L. Mills

Organizations

  • University of Maryland

Tags

Communities of Interest

  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Analogs
  • Automatic Gain Control
  • Computer Programming
  • Computer Programs
  • Computers
  • Converters
  • Decoding
  • Detectors
  • Filtration
  • Frequency
  • Markov Models
  • Morse Code
  • Operating Systems
  • Probability
  • Processing Equipment
  • Signal Processing
  • Test Equipment

Fields of Study

  • Engineering

Readers

  • Calculus or Mathematical Analysis
  • Computer Science.
  • Radio communications and signal processing.