Patent · US Expired

Data system

US4701938A · kind A · utility

22Cited by
5References
23Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 31, 1985
Grant dateOct 20, 1987
Priority date
Expiry dateOct 31, 2005

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04Q9/14
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A data system for transmitting multi-state data streams between a data transmitting station (1,10) and a data receiving station (2), coupled together by a data transmission line (3). Associated with the data transmitting station (1,10) is an encoder (10) for encoding the data stream prior to transmission and associated with the data receiving station (2) is a decoder (23,24) for decoding the received signals. The encoder (10) comprises signal generating means (15,16,17) which selectively generates a first waveform (FIG. 2(b) (i)) corresponding to the integral of a positive pulse having a negative d.c. offset and a second waveform (FIG. 2(b) (ii)) corresponding to the integral of a negative pulse having a positive d.c. offset. The time average of each waveform and its associated d.c. offsets is substantially zero. The encoder (10) further comprises means (18) for reading the multi-state data stream and for outputting a composite waveform onto the data transmission line (3) consisting of a respective combination of the first and second waveforms for each state read from the multistate data stream. The decoder (23,24) comprises a differentiating circuit.

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