INTERCOM TRANSCEIVER WITH FIBER OPTIC LINK

• US 20130287400A1
• Filed: 03/13/2013
• Published: 10/31/2013
• Est. Priority Date: 04/26/2012
• Status: Active Grant

• Current Assignee: Grass Valley Canada (Belden Inc.)
• Original Assignee: Miranda Technologies Partnership
• Inventors: Hurwitz, James Bennett, Pelletier, David Charles
• Granted Patent: US 9,143,233 B2
• Time in Patent Office: Days
• US Class Current: 398/79
• CPC Class Codes: H04B 10/2575 Radio-over-fibre, e.g. radio frequency signal modulated onto an optical carrier
• CPC Class Codes: H04B 10/25751 Optical arrangements for CATV or video distribution adaptations of television systems for optical transmission H04N7/22
• CPC Class Codes: H04B 10/2589 Bidirectional transmission
• CPC Class Codes: H04J 2203/0001 Provisions for broadband connections in integrated services digital network using frames of the Optical Transport Network [OTN] or using synchronous transfer mode [STM], e.g. SONET, SDH
• CPC Class Codes: H04M 11/025 Door telephones adapted for television H04N7/186

Abstract

A system and method for carrying a downstream optical signal and an upstream optical signal on a fiber optic link is disclosed. The system and method includes a first transceiver unit that receives an input communication signal from at least one external communication device at an electrical input port, a transmitter that converts the input communication signal into an optical signal and transmits the optical signal as an downstream optical signal on a fiber optic link, a receiver at the second transceiver unit that receives the downstream optical signal and converts the downstream optical signal into an electrical communication signal, and a first circuit in the second transceiver unit that determines whether the second transceiver couples the electrical communication signal to a two wire intercom circuit or a four wire intercom circuit.

Claims

1. A system for carrying a downstream optical signal and an upstream optical signal on a fiber optic link between a first transceiver unit coupled to a first intercom system and a second transceiver unit coupled to a second intercom system, the system comprising:

a first transceiver unit that receives an input communication signal from at least one external communication device at an electrical input port;

a transmitter that converts the input communication signal into an optical signal and transmits the optical signal as a downstream optical signal on a fiber optic link coupled between the first transceiver unit and the second transceiver unit;

a receiver at the second transceiver unit that receives the downstream optical signal and converts the downstream optical signal into an electrical communication signal;

a first circuit in the second transceiver unit that determines whether the second transceiver unit couples the electrical communication signal to a two wire intercom circuit or a four wire intercom circuit; and

an output port on the second transceiver unit that outputs either a two wire intercom signal or a four wire intercom signal to an external communication device based on the first circuit determination.

2. The system of claim 1, further comprising a second circuit in the second transceiver unit that selects a communication protocol for the electrical communication signal.

3. The system of claim 2, further comprising a third circuit in the second transceiver unit that determines whether the second transceiver unit couples the electrical communication signal to a four wire intercom station circuit or a four wire intercom matrix circuit in the case that the first circuit determines the electrical communication signal is coupled to a four wire intercom circuit.

4. The system of claim 3, further comprising a fourth circuit in the second transceiver unit that determines a power source for an external communication device coupled to the electrical communication signal in the case that the first circuit determines the electrical communication signal is coupled to a two wire intercom circuit.

5. The system of claim 4, wherein the first circuit determination is based on a switch position of a first switch located on an external surface of the second transceiver unit, the second circuit determination is based on a switch position of a second switch located on the external surface of the second transceiver unit, the third circuit determination is based on a switch position of a third switch located on an external surface of the second transceiver unit, and the fourth circuit determination is based on a switch position of a fourth switch located on an external surface of the second transceiver unit.

6. The system of claim 4, wherein the power source is one of a battery contained within the exterior surface of the transceiver unit and an external direct current power supply.

7. The system of claim 1, wherein the fiber optic link is a single mode fiber.

8. The system of claim 1, wherein the input communication signal comprises an intercom audio channel.

9. The system of claim 1, wherein the input communication signal comprises a plurality of intercom audio channels time division multiplexed prior to optical to electrical conversion at the first transceiver.

10. The system of claim 9, wherein the input communication signal further comprises a data signal time division multiplexed with the plurality of audio channels prior to optical to electrical conversion at the first transceiver.

11. The system of claim 1, further comprising an input/output port at the second transceiver coupled to the fiber-optic link.

12. The system of claim 11, further comprising a wavelength division multiplexer coupled to the fiber input/output port at the second transceiver for multiplexing the downstream optical signals and the upstream optical signals to permit bidirectional communication on the single fiber optic cable.

13. The system of claim 2, wherein the first circuit determination and the second circuit determination are received as switch control signals at a processing circuit that transmits circuit control signals based on the switch control signals to internal circuits within the second transceiver unit to electrically couple the electrical communication signal to an output port of the second transceiver unit.

14. A method of carrying a downstream optical signal and an upstream optical signal on a fiber optic link between a first transceiver coupled to a first intercom system and a second transceiver coupled to a second intercom system, the method comprising:

receiving an input communication signal from at least one external communication device at an electrical input port of a first transceiver unit;

converting the input communication signal into an optical signal;

transmitting the optical signal as a downstream optical signal on a fiber optic link coupled between the first transceiver unit and the second transceiver unit;

receiving the optical signal as a downstream optical signal at the second transceiver unit;

converting the downstream optical signal into an electrical communication signal;

coupling the electrical communication signal to one of a two wire intercom circuit and a four wire intercom circuit determined by a first circuit in the second transceiver unit; and

transmitting one of a two wire intercom signal or a four wire intercom signal to an external communication device based on the first circuit determination.

15. The method of claim 14, further comprising determining a communication protocol for the electrical communication signal at a second circuit in the second transceiver unit;

16. The method of claim 15, further comprising determining, at a third circuit in the second transceiver unit, whether the second transceiver unit couples the electrical communication signal to a four wire intercom station circuit or a four wire intercom matrix circuit if the first circuit determines the electrical communication signal is coupled to a four wire intercom circuit.

17. The method of claim 16, further comprising determining, at a fourth circuit in the second transceiver unit, a power source for an external communication device coupled to the electrical communication signal if the first circuit determines the electrical communication signal is coupled to a two wire intercom circuit.

18. The method of claim 17, wherein the first circuit determination is based on a switch position of a first switch located on an external surface of the second transceiver unit, the second circuit determination is based on a switch position of a second switch located on the external surface of the second transceiver unit, the third circuit determination is based on a switch position of a third switch located on an external surface of the second transceiver unit, and the fourth circuit determination is based on a switch position of a fourth switch located on an external surface of the second transceiver unit.

19. The method of claim 17, wherein the power source is one of a battery contained within the exterior surface of the transceiver unit and an external direct current power supply.

20. The method of claim 14, wherein the fiber optic link is a single mode fiber.

21. The method of claim 14, wherein the input communication signal comprises an intercom audio channel.

22. The method of claim 14, wherein the input communication signal comprises a plurality of audio channels time division multiplexed prior to optical to electrical conversion.

23. The method of claim 22, wherein the input communication signal further comprises a data signal time division multiplexed with the plurality of audio channels prior to optical to electrical conversion.

24. The method of claim 14, further comprising an input/output port at the second transceiver unit coupled to the fiber-optic cable.

25. The method of claim 20, further comprising a wavelength division multiplexer coupled to the fiber input/output port at the second transceiver unit for multiplexing the downstream optical signals and the upstream optical signals to permit bidirectional communication on the single fiber optic cable.

26. The method of claim 15, wherein the first circuit determination and the second circuit determination are received as switch control signals at a processing circuit that transmits circuit control signals based on the switch control signals to internal circuits within the second transceiver unit to electrically couple the electrical communication signal to an output port of the second transceiver unit.

27. A system receiving a downstream optical signal at a transceiver unit coupled to an intercom system, the system comprising:

a receiver at the transceiver unit that receives the downstream optical signal and converts the downstream optical signal into an electrical communication signal;

a first circuit in the transceiver unit that determines whether the transceiver unit couples the electrical communication signal to a two wire intercom circuit or a four wire intercom circuit; and

an output port on the transceiver unit that outputs either a two wire intercom signal or a four wire intercom signal to an external communication device based on the first circuit determination.

28. The system of claim 27, further comprising a second circuit in the transceiver unit that selects a communication protocol for the electrical communication signal.

29. The system of claim 28, further comprising a third circuit in the transceiver unit that determines whether the transceiver unit couples the electrical communication signal to a four wire intercom station circuit or a four wire intercom matrix circuit in the case that the first circuit determines the electrical communication signal is coupled to a four wire intercom circuit.

30. The system of claim 29, further comprising a fourth circuit in the transceiver unit that determines a power source for an external communication device coupled to the electrical communication signal in the case that the first circuit determines the electrical communication signal is coupled to a two wire intercom circuit.

31. The system of claim 30, wherein the first circuit determination is based on a switch position of a first switch located on an external surface of the transceiver unit, the second circuit determination is based on a switch position of a second switch located on the external surface of the transceiver unit, the third circuit determination is based on a switch position of a third switch located on an external surface of the transceiver unit, and the fourth circuit determination is based on a switch position of a fourth switch located on an external surface of the transceiver unit.