CA2171902A1 - Infra red communication systems - Google Patents

Infra red communication systems

Info

Publication number
CA2171902A1
CA2171902A1 CA002171902A CA2171902A CA2171902A1 CA 2171902 A1 CA2171902 A1 CA 2171902A1 CA 002171902 A CA002171902 A CA 002171902A CA 2171902 A CA2171902 A CA 2171902A CA 2171902 A1 CA2171902 A1 CA 2171902A1
Authority
CA
Canada
Prior art keywords
channel
photodetector
infra red
receiving
transmitter
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
CA002171902A
Other languages
French (fr)
Inventor
Laith Faris Samarai
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
CALEDONIAN AIRBORNE SYSTEMS Ltd
Original Assignee
CALEDONIAN AIRBORNE SYSTEMS LIMITED
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by CALEDONIAN AIRBORNE SYSTEMS LIMITED filed Critical CALEDONIAN AIRBORNE SYSTEMS LIMITED
Priority to CA002171902A priority Critical patent/CA2171902A1/en
Publication of CA2171902A1 publication Critical patent/CA2171902A1/en
Abandoned legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R3/00—Circuits for transducers, loudspeakers or microphones
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/02—Constructional features of telephone sets
    • H04M1/04—Supports for telephone transmitters or receivers
    • H04M1/05—Supports for telephone transmitters or receivers specially adapted for use on head, throat or breast
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R5/00—Stereophonic arrangements
    • H04R5/033—Headphones for stereophonic communication
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R2420/00—Details of connection covered by H04R, not provided for in its groups
    • H04R2420/07—Applications of wireless loudspeakers or wireless microphones

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Health & Medical Sciences (AREA)
  • Otolaryngology (AREA)
  • Optical Communication System (AREA)

Abstract

A transmitter (10) and one or more receivers (12) are linked by infra red transmission via LED (14) and photodiode (16). In normal use, in-flight entertainment is modulated on left and right channels to give stereo sound on a user's earphones (28a, 28b). Transmitter public address signal on one channel and a code signal on the other channel. At the receiver (12), the code is detected (at 36) to operate receiver switching means (38) which disable the user's volume controls (30), thus ensuring that the public address message is heard at full volume. Also described are improved infrared signal receiving arrangements mitigating the effects of ambient light interference.

Claims (11)

1. A communication system comprising a master station including a transmitter, and a plurality of receiving stations, each receiving station having a respective individual volume control; and the master station includes means for overriding the volume controls of the receiving stations.
2. A system according to claim 1, which uses infra red transmission between the transmitter and the receiving stations.
3. A system according to claim 1 or claim 2, which is a stereo system having two channels and the overriding means comprises:
means in the master station for transmitting a code signal on one channel, and means in each receiving station responsive to said code signal to disable said one channel and to bypass the volume control of the other channel.
4. A system according to claim 3, in which the code signal is a continuous monotone.
5. A receiving apparatus for use in an infra red communication system, the apparatus being in the form of a head set having left and right earpieces joined by a head band, the apparatus including a plurality of photodetectors positioned on the head set and facing in different directions.
6. Apparatus according to claim 5, in which there are four photodetectors positioned one at the front and one at the rear of each earpiece.
7. Apparatus according to claim 5 or claim 6, including circuit means operating to reduce the signal from a given photodetector as the light incident thereon increases.
8. Apparatus according to claim 7, in which the circuit means comprises a feed-forward system.
9. Apparatus according to claim 8, in which the feed forward system, for each photodetector, includes a load element which provides a load resistance which varies inversely with the output current of the photodetector.
10. Apparatus according to claim 9, in which the load element is a bipolar transistor.
11. Apparatus according to claim 10, including a constant current source connected in parallel with the photodetector to the transistor emitter.
CA002171902A 1996-03-15 1996-03-15 Infra red communication systems Abandoned CA2171902A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CA002171902A CA2171902A1 (en) 1996-03-15 1996-03-15 Infra red communication systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CA002171902A CA2171902A1 (en) 1996-03-15 1996-03-15 Infra red communication systems

Publications (1)

Publication Number Publication Date
CA2171902A1 true CA2171902A1 (en) 1997-09-16

Family

ID=4157756

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002171902A Abandoned CA2171902A1 (en) 1996-03-15 1996-03-15 Infra red communication systems

Country Status (1)

Country Link
CA (1) CA2171902A1 (en)

Similar Documents

Publication Publication Date Title
US4959828A (en) Multi-channel infrared cableless communication system
MY105660A (en) Wireless headphones
JP2005515662A5 (en)
JP2970844B2 (en) Optical receiver and optical network system using the same
CA2171902A1 (en) Infra red communication systems
EP0740894B1 (en) Infrared communication system
US5483371A (en) Lightwave distribution system for audio and video services and terminal equipment therefor
CA2314854A1 (en) Optical communication system optically combining both baseband and passband signals
JPH04243331A (en) Optical wireless transmitter
RU543U1 (en) Stereo IR sound transmission system
JP4076406B2 (en) Audio transmitter
KR200281232Y1 (en) Wireless Remote controller having audio signal receiver
GB2279195A (en) Infra-red headphones
JPS57103445A (en) Optical communication device
JPS6253032A (en) Optical fiber two-way transmission system
JPH11308687A (en) Infrared-ray synchronizing type remote control transmitter-receiver
JP2004254207A (en) Infrared wireless headphone device
JPH08204650A (en) Point-multipoint optical transmission system
RU2223604C1 (en) Wireless optical communication system
JPH0396022A (en) Optical transmission stereo reproduction device
Griese Conference Systems Using Infrared Light Techniques
JP2003163987A (en) Rear entertainment system
JPS63208395A (en) Receiver for wireless system
JPS58125919A (en) Transmitting device
JP2006222767A (en) Multi-channel infrared receiver and multi-channel infrared transmitting/receiving system

Legal Events

Date Code Title Description
FZDE Discontinued