Patent · US Expired

Facsimile communication system

US3974326A · kind A · utility

7Cited by
4References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 6, 1976
Grant dateAug 10, 1976
Priority date
Expiry dateJan 6, 1996

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N1/419
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A black and white facsimile communication system wherein the document to be transmitted is scanned line by line, the scanner signals are sampled to obtain pulse sequences having a constant number of pulses for every line. The pulse sequences are converted into codewords for redundancy reduction. The codewords are transmitted and, in the receiver, reconverted into pulse sequences which control reproduction. Before reproduction every pulse sequence obtained by reconversion is tested whether it contains the correct number of pulses. If that is not the case, the last reproduced line is reproduced again instead of the line received with an error.

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