Methods and apparatus for underwater wireless optical communication

• US 20050232638A1
• Filed: 04/04/2005
• Published: 10/20/2005
• Est. Priority Date: 04/02/2004
• Status: Abandoned Application

• Current Assignee: Woods Hole Oceanographic Institution
• Original Assignee: Woods Hole Oceanographic Institution
• Inventors: Zhang, Jack, Fucile, Paul, Tivey, Maurice, Sichel, Enid
• Application Number:
  US11/099,013
• Publication Number:
  US 20050232638A1
• Time in Patent Office: Days
• US Class Current: 398/140
• CPC Class Codes: H04B 13/02 Transmission systems in which the medium consists of the earth or a large mass of water thereon, e.g. earth telegraphy

Abstract

Low-power, wireless, underwater communication devices with communication capabilities without requiring precision underwater navigation. In one aspect, the systems and methods described herein relate to a transmitter which wirelessly transmits data underwater using light-emitting diodes and a receiver which wirelessly receives data emitted from light-emitting diodes using a photodiode. In one embodiment the light-emitting diodes are blue and in another embodiment the light-emitting diodes are red. The receiving photodiode can, for example, be a silicon photodiode. In yet other embodiments the transmitter transmits data to the receiver according to a standard protocol, for example, the IRDA protocol. In one embodiment the transmitter can communicate with receivers as far as 5 to 10 meters away from the transmitter.

Claims

1. A communication system, comprising

an optical transducer having an optical transmitter with a single or array of light emitting diodes for generating light within a bandwidth of approximately 400-700 nm,

an optical receiver with a single or array of photo detector elements of the type capable of detecting light within the communication bandwidth, and

a face plate with a lens disposed in front of the array of receiving photo diodes,

a watertight housing sealed to the optical transducer and defining an interior chamber, and

a circuit in electrical communication with the optical transmitter and the optical receiver and a communication controller for driving the array of light emitting diodes according to the IRDA communication protocol.

2. A communication system according to claim 1, further comprising

A power cell disposed within the watertight housing and electrically coupled to the circuit and to the optical-transducer to provide power thereto.

3. A communication system according to claim 2, wherein the power cell is selected from the group consisting of a battery or other stored energy source.

4. A communication system according to claim 1, wherein the watertight housing is dimensionally adapted to fit on a manipulator of the type used with an underwater vehicle or in an underwater environment.

5. A communication system according to claim 1, further comprising

a clamp coupled to the watertight housing for securing the watertight housing to a moveable or stationary member.

6. A communication system according to claim 1, wherein the optical transmitter comprises an array of multiple light emitting diodes.

7. A communication system according to claim 1 wherein

the circuit includes a driver for driving the array of multiple light emitting diodes to transmit data at a rate of between 9600 BAUD (Bits Per Second) to 4 NBAUD.

8. A communication system according to claim 1, wherein light emitting diodes to transmit data at a rate of between 9600 BAUD (Bits Per Second) to 4 MBAUD.

9. A communication system according to claim 1, wherein the lens comprises a light collecting lens disposed in front of the array of light emitting diodes for collecting light to direct light onto receiving photodiode.

10. A communication system according to claim 1, further comprising

A telemetry interface for exchanging data to a location external to the watertight housing.

11. A communications system according to claim 1, further comprising

an acoustic sound generator coupled to the photodetector so that a person in a submarine guiding the light beam between the transmitter and the receiver can receive a feedback message to keep the light beam hitting the receiver and maintain a communication link.

12. A communications system according to claim 1, further comprising

a low power sleep mode allowing the communication module to turn itself off by timed prearrangement or by lack of incoming signals.

13. A communications system according to claim 12, further comprising

a wake-up processor for causing the device to enter into an active state in response to being interrogated by a light beam from the transmitter or by incoming signals to the detector or by prearranged timing.

17. A communication device, comprising

a plurality of optical communication devices as recited in claim 1,

a data communication network interconnected among the plurality of optical communication devices.

18. A communication device as recited in claim 17, further comprising

a data hub for providing data communication among a plurality of devices.

19. A communication device as recited in claim 17, further comprising

a plurality of sensors coupled in a data communicating relationship with the data communication network.

14. A sensor, comprising

a sensing transducer of the type capable of measuring a physical parameter and generating an information signal representative of that physical parameter, and

an optical communication system having

an optical transducer with a single or array of light emitting diodes for transmitting a communication signal within a wavelength bandwidth of between 400-700 nm, a single or array of photo detectors of the type capable of detecting light within a bandwidth of between 400-700 mm, and a face plate being transmissive to light and having a lens disposed in front of the array of light emitting diodes for collecting light to focus the light onto the photodiode,

a circuit in electrical communication with the optical transducer, the array of light emitting diodes and the array of photodetectors, and

a watertight housing surrounding the optical communication system and the sensing transducer.

15. A sensor according to claim 14, wherein the sensing transducer comprises a plurality of sensing transducers.

16. A sensor according to claim 15, wherein the sensing transducer comprises a network having a plurality of distributed sensing transducers,

20. A method for manufacturing a communications device, comprising

forming an optical transmitter from a single or array of light emitting diode(s) capable of generating light within a bandwidth of approximately 400-700 nm,

forming an optical receiver with a single or array of photo detector(s) elements of the type capable of detecting light of a wavelength within the communication bandwidth, and

disposing the optical transmitter and the optical receiver within a watertight housing and placing a face plate with a lens in front of the array of light emitting diode(s) and photodiodes,

providing a watertight housing sealed to the optical transducer and defining an interior chamber, and disposing therein a circuit in electrical communication with the optical transmitter and the optical receiver and a communication controller for driving the LED array according to the IRDA communication protocol.

21. A method according to claim 20, comprising the further step of coupling a sensor to the communication device.

22. A method according to claim 20, comprising the further step of providing a data terminal for communicating data to a source that is external to the watertight housing.

23. A method according to claim 22, comprising the further step of providing a data network capable of communicating data among multiple devices.