Patent · US Expired

Wide-angle, high-speed, free-space optical communications system

US5606444A · kind A · utility

107Cited by
5References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 20, 1994
Grant dateFeb 25, 1997
Priority date
Expiry dateOct 20, 2014

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04B10/40
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A free-space optical communications system for transmitting data between an aircraft computer system (14) and a ground-based computer system (12). The system includes a pair of corresponding optical transmitters (36) and optical receivers (38) that transmit and receive optical signals transmitted between the two computer systems. Included within each optical transmitter is one or more light-emitting diodes (42) that produce optical signals corresponding to the data to be transmitted. A beam-forming horn (44) is bonded directly to the light-emitting diodes to direct the optical signal uniformly over a target area. The optical receiver includes one or more infrared windows (50) to reduce the mount of ambient light received by the optical receiver. A compound parabolic concentrator (64) collects light transmitted from the optical transmitter and directs the light onto an avalanche photodiode (66), which includes thermal bias compensation. An AC network couples the output signal of the photodiode to a transimpedance amplifier (70). An optional optical shroud (34) surrounds the optical transmitters and receivers to further reduce the amount of ambient light that is received by the optic…

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