Patent · US Expired

Infrared echo canceling

US5838471A · kind A · utility

16Cited by
3References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 27, 1996
Grant dateNov 17, 1998
Priority date
Expiry dateJun 27, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04B10/11
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

An infrared data communications system employs echo cancellation to remove echo signals of infrared transmissions received by an infrared receiver transducer. A version of the data pulse signal to be transmitted is subtractively combined with the received data pulse signal in order to remove echos of the transmitted signal from the received data pulse signal. A pulse stretcher circuit is utilized to increase the pulse width duration of the version of the data pulse signal to be combined with the received data pulse signal in order to ensure correct timing and cancellation of received echo signals over a range of echo signal propagation delay time.

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