Application of Multi-Frequency Modulation (MFM) Facsimile Machines

Abstract

Multi-Frequency Modulation (MFM) has been developed at NPS using both differential quadrature-amplitude-modulation (DQAM) and differential quadrature- phase-shift-keying (DQPSK) encoding formats. This report discusses the use of each of these formats in transmitting a facsimile encoded message over a voice frequency channel. The satisfactory transmission and receipt of facsimile messages was achieved using both DQPSK and D16-QAM encoding formats. Research and testing for this report included the use of variable facsimile transmission rates in an attempt to optimize MFM operating parameters. Experimental results revealed a higher error rate when decoding messages contained similar contiguous characters.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1990
Accession Number
ADA241041

Entities

People

  • James T. Nickerson

Organizations

  • Naval Postgraduate School

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Abstracts
  • Amplitude
  • Amplitude Modulation
  • Coding
  • Communications Techniques
  • Computer Programming
  • Computers
  • Decoding
  • Digital Communications
  • Facsimile Transmission
  • Frequency
  • Frequency Modulation
  • Modulation
  • Modulators
  • Phase Shift
  • Transmitting
  • Two Dimensional

Fields of Study

  • Computer science

Readers

  • Radio communications and signal processing.