• DocumentCode
    940965
  • Title

    Multifrequency tone detection by zero-interval analysis

  • Author

    Smith, C.S.A.

  • Author_Institution
    Post Office Research Department, Ipswich, UK
  • Volume
    13
  • Issue
    1
  • fYear
    1977
  • Firstpage
    3
  • Lastpage
    4
  • Abstract
    An algorithm is presented which enables a microprocessor to analyse the zero intervals of the multifrequency signals from a pushbutton telephone. A model has shown that, with a 100 kHz clock, the component frequencies of any signal can be predicted to within ±1% from a 30 ms sample, but the speech immunity requires improvement.
  • Keywords
    computerised signal processing; signal detection; telephone sets; microprocessor; multifrequency tone detection; pushbutton telephone; zero interval analysis;
  • fLanguage
    English
  • Journal_Title
    Electronics Letters
  • Publisher
    iet
  • ISSN
    0013-5194
  • Type

    jour

  • DOI
    10.1049/el:19770003
  • Filename
    4240326
    • Link To Document
    https://search.isc.ac/dl/search/defaultta.aspx?DTC=49&DC=940965