Classifier for high speed voiceband digital data modem signals

Number of patents in Portfolio can not be more than 2000

United States of America Patent

PATENT NO 4979211
SERIAL NO

07534321

Stats

ATTORNEY / AGENT: (SPONSORED)

Importance

Loading Importance Indicators... loading....

Abstract

See full text

An unknown voiceband digital data modem signal is classified as being generated by one of a plurality of possible digital data modem signal sources, e.g., CCITT V.29, CCITT V.32, CCITT V.33 or the like digital data modems. Classification is achieved by employing a blind, i.e., self-recovering, adaptive equalizer to remove effects of linear channel impairments and to generate a sequence of magnitude estimates at the symbol rate of the unknown voiceband digital data modem signal. The sequence of magnitude estimates is compared to predetermined representations of known possible voiceband digital data modem signals and the results of the comparison are used to identify the digital data modem signal source of the signal. In one example, the predetermined representations are templates of conditional density functions of magnitude estimates obtained from known voiceband digital data modem signals generated by corresponding digital data modem signal sources. The symbol rate detector detects bit rate and type of modulation.

Loading the Abstract Image... loading....

First Claim

See full text

Family

Loading Family data... loading....

Patent Owner(s)

Patent OwnerAddress
AT&T BELL LABORATORIESNEW YORK UNITED STATES NEW YORK

International Classification(s)

  • [Classification Symbol]
  • [Patents Count]

Inventor(s)

Inventor Name Address # of filed Patents Total Citations
Benvenuto, Nevio Mestre, IT 8 240
Goeddel, Thomas W Fair Haven, NJ 9 192

Cited Art Landscape

Load Citation

Patent Citation Ranking

Forward Cite Landscape

Load Citation