Patent · US Expired

Digital communication device

US5818870A · kind A · utility

15Cited by
21References
38Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 22, 1991
Grant dateOct 6, 1998
Priority date
Expiry dateAug 22, 2011

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04Q2213/297
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A digital communication device of the present invention is provided with a modulation circuit for modulating a digital transmit signal, a first interpolater for converting the modulated signal in frequency, a coding circuit for coding the signal converted in frequency into an audio PCM transmission code with reference to a voice companding code table, a decoding circuit for decoding a coded audio PCM receive code into a digital signal with reference to the voice companding code table, a second interpolater for converting the decoded digital signal in frequency, and a demodulation circuit for demodulating the converted signal, and digitally performs modem modulation/demodulation and voice codec processing.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.