Patent · US Expired

Communication apparatus for transmitting and receiving communication signals through common transmission line

US5355390A · kind A · utility

15Cited by
9References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 16, 1991
Grant dateOct 11, 1994
Priority date
Expiry dateMay 16, 2011

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L25/0292
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A transmitting circuit is provided which includes a control circuit for transmitting and receiving a communication signal. Transmit information is modulated into a trapezoidal wave signal using a waveform shaping circuit. A communication signal is first generated on the basis of the trapezoidal wave signal and transmitted to a first transmission line. From this communication signal, a second communication signal is generated having an inverted polarity waveform shape relative to the first communication signal. This inverted polarity triangular wave signal is, in turn, output from a second transmission line BUS-. In addition, a receiving circuit is provided for receiving like signals from other communication devices which share the first and second transmission lines BUS+ and BUS-. The receiving circuit includes a comparator circuit for demodulating received signals on the transmission lines to generate square wave equivalent signals which a processing unit can logically interpret. Because communication signals are transmitted (received) and derived in the described manner, they are not subject to adverse effects, such as can result from fluctuation of GND potential levels and power…

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