Data telemetry system using diffused infrared light

• US 4,717,913 A
• Filed: 08/29/1985
• Issued: 01/05/1988
• Est. Priority Date: 08/29/1985
• Status: Expired due to Fees

• Current Assignee: Johnson Service Company
• Original Assignee: Johnson Service Company
• Inventors: Elger, Rodney R.
• Primary Examiner(s): Weldon, Ulysses
• Assistant Examiner(s): Smith, Ralph E.
• Application Number:
  US06/770,680
• Time in Patent Office: 859 Days
• Field of Search: 340/825.54, 340/825.72, 455/603, 455/606, 455/607, 455/613, 455/605, 455/617, 455/619, 455/604
• US Class Current: 340/10.1
• CPC Class Codes: G08C 23/04 using light waves, e.g. infrared
• CPC Class Codes: H04B 10/1149 Arrangements for indoor wireless networking of information
• CPC Class Codes: H04B 10/116 Visible light communication
• CPC Class Codes: H04B 10/40 Transceivers

Abstract

A data telemetry system for process control includes a point transponder adapted to receive digitally coded infrared interrogation signals. The transponder includes a first group of positive, intrinsic, negative (PIN) diodes disposed thereon for omnidirectionally detecting interrogation signals and a second group of infrared emitting diodes for generating digitally coded signals responsive to the interrogation signals. The first group and the second group of diodes define a first array of diode nodes, each node including at least one diode from each group. A transceiver includes a generally hemispherical, omnidirectional transmitting and receiving member having a third group of infrared emitting diodes disposed thereon for generating the interrogation signals and a fourth group of PIN diodes for receiving the responsive signals from the transponder. The third and fourth groups define a second array of diode nodes, each node including at least one diode from each other. The interrogation signals received at the transponder and responsive signals received at the transceiver are formed at least in part of diffuse infrared light.

Claims

1. A data telemetry system for process control comprising:

a plurality of point transponders for receiving digitally coded interrogation signals, each of said transponders including a first group of PIN diodes disposed thereon for omnidirectionally detecting said interrogation signals and a second group of IR emitting diodes disposed thereon for generating digitally coded signals responsive to said interrogation signals;

said first group and said second group defining a first array of diode nodes, each of said first array nodes being mounted upon a generally planar surface and including at least one diode of said first group and at least one diode of said second group;

each of said point transponders further including an element defined by at least three planar surfaces arranged in a polyhedran configuration, said element having a dome disposed thereover for protecting said element, wherein said dome is configured of a material to act as an optical band pass filter;

a transceiver including a generally hemispherical reflective member having a third group of IR emitting diodes disposed thereon for generating said interrogation signals and a fourth group of PIN diodes disposed thereon for receiving said responsive signals;

said third group and said fourth group defining a second array of diode nodes, each of said second array nodes including at least one diode of said third group and at least one diode of said fourth group;

each of said IR emitting diodes including a dedicated driver physically closely coupled thereto, each of said drivers comprising an integrated circuit of the MOSFET type and being powered by a pulse position modulator.

2. A data telemetry system for use in controlling heating, ventilating and air conditioning apparatus, said system including:

a point transponder for receiving digitally coded interrogation signals formed of diffuse infrared light reflected from at least one surface intermediate said transponder and a transceiver, said transponder including a body member and a head member positionably attached to said body member;

said head member including a transmitter module and a receiver module, said body member including means for modulating a signal to be directed to said transmitter module and means for demodulating an infrared light signal received at said receiver module;

said point transponder further including an element defined by at least three planar surfaces arranged in a polyhedran configuration, said element having a dome disposed thereover for protecting said element, wherein said dome is configured of a material to act as an optical band pass filter;

a transceiver for connection to a local control unit, said transceiver including a satellite having a face member and a reflective member attached to said face member, said face member being mountable to a surface within a room;

said reflective member having a group of IR emitting diodes disposed thereon for generating said interrogation signals, said diode group and said reflective member cooperating for radiating said interrogation signals in a generally hemispherical pattern bounded by said mounting surface;

said point transponder including a group of IR emitting diodes, each of said IR emitting diodes including a dedicated driver closely coupled thereto, each of said drivers comprising an integrated circuit of the MOSFET type and being powered by a pulse position modulator.