Fiber optic network using space and wavelength multiplexed data channel arrays

• US 5,912,751 A
• Filed: 08/01/1996
• Issued: 06/15/1999
• Est. Priority Date: 05/28/1996
• Status: Expired due to Term

• Current Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Krishnamoorthy, Ashok V., Knox, Wayne H., Ford, Joseph E., Miller, David A. B., Nuss, Martin C.
• Primary Examiner(s): NEGASH, KINFE MICHAEL
• Application Number:
  US08/691,101
• Time in Patent Office: 1,048 Days
• Field of Search: 359/117, 359/123, 359/128, 359/139, 359/152
• US Class Current: 398/46
• CPC Class Codes: H04B 10/506 Multiwavelength transmitters
• CPC Class Codes: H04J 14/02 Wavelength-division multiplex systems
• CPC Class Codes: H04Q 11/0005 Switch and router aspects
• CPC Class Codes: H04Q 2011/0016 using wavelength multiplexing or demultiplexing
• CPC Class Codes: H04Q 2011/0026 using free space propagation (e.g. lenses, mirrors)

Abstract

A network for multi-bit word parallel communication between optoelectronic chips on a two dimensional array of optical input and output channels carried on a single dimension of optical fibers. Each bit of a word is carried on a different wavelength and the multiple wavelengths carrying a word are wavelength multiplexed onto a single optical fiber. Multiple fibers can be joined into a one dimensional array of fibers. A transceiver for transmitting and receiving along the optical data channels comprises an array of modulators powered by individual wavelength light beams, either from individual monochromatic light sources and a light beam from a single broadband light source made to pass through a diffraction grating. The modulators are positioned so that each modulator reflects a different wavelength light beam, thereby providing multiple optical channels. Alternatively, multiple wavelengths are generated from CMOS integrated light sources. These multiple optical channels are then collimated and guided into one single mode fiber or multiple multimode fibers at its transmitting end. At the receiving end a diffraction grating is used to separate the distinct data channels by their individual wavelengths. The multiple wavelengths are then caused to fall on an array of optical detectors spaced according to the individual wavelengths to be detected. By constructing a one dimensional array of these fibers, a two dimensional array of optical data channels is realized. The size of the array is determined by the number of fibers and the number of distinct wavelengths combined in each fiber.

Claims

1. An optical network using space and wavelength multiplexed data channel arrays, comprising:

a plurality of optical network interfaces, each of said optical network interfaces having an optoelectronic transceiver, wherein said transceiver transmits and receives multi-bit word data wherein each bit in said multi-bit word is carried on a single distinct wavelength and said multi-bit word is communicated as wavelength division multiplexed data; and

an interconnection switch for connecting one or more of said plurality of optical network interfaces.

2. A network according to claim 1 wherein communications between each of said transceivers and said interconnection switch are transported over single mode optical fiber.

3. A network according to claim 1 wherein said interconnection switch is a bit-sliced optoelectronic interconnection switch.

4. An optical network according to claim 3 wherein each of said multi-bit words comprise K bits said bit-sliced optoelectronic interconnection switch comprises:

a two dimensional array of N×

K optolectronic input devices for detecting said K bit words carried on N×

K beams of light corresponding to N data input channels of K bit streams each;

K interconnection units each having N input ports for receiving said K bit words carried on N input data channels and N output ports for transmitting said K bit words to be carried on N output data channels, each of said K interconnection units for routing one bit of each of said K bit words from each of said N input data channels to said N output data channels;

one or more controllers for determining to which of said N output channels of each of said K interconnection units to route said K bit words carried on a given input data channel; and

a two dimensional N×

K array of optoelectronic output devices for modulating said K bit words to be carried on said N output channels of K bit streams each.

5. A network according to claim 4 wherein said bit-sliced optoelectronic interconnection switch is powered by a plurality of monochromatic light sources.

6. A network according to claim 5 wherein said plurality of monochromatic light sources are CMOS integrated light sources.

7. A network according to claim 6 wherein said CMOS integrated light sources are VCSELs.

8. A network according to claim 4 wherein said bit-sliced optoelectronic interconnection switch is powered by a single broadband light beam, said single broadband light beam made to pass through a diffraction grating so as to separate said broadband light beam into a plurality of monochromatic light beams, such that each of said monochromatic light beams is incident on and reflected from a modulator, thereby transmitting a signal.

9. A network according to claim 1 wherein each of said transceivers comprise:

means for generating a plurality of monochromatic output light beams, each of said monochromatic light beams to optically encode one bit in a word,

means for guiding said plurality of said monochromatic light beams into one or more of said optical output fibers;

means for receiving one or more of said optical input fibers, each of said optical input fibers carrying wavelength division multiplexed data on a plurality of input light beams;

means for separating said input light beams into distinct monochromatic light beams; and

means for detecting said wavelength division multiplexed data carried on said distinct monochromatic light beams.

10. A network according to claim 9 wherein said means for generating a plurality of monochromatic output light beams comprises a plurality of modulators.

11. A network according to claim 10 wherein said modulators are MQW diodes.

12. A network according to claim 10 wherein said modulators are powered by a single broadband light beam and said means for generating further comprises a diffraction grating for separating said broadband light beam into multiple monochromatic light beams, so that each beam is incident on a different one of said modulators.

13. A network according to claim 12 wherein said broadband light beam has a given diameter and said means for generating step further comprises:

means for expanding said diameter of said broadband light beam; and

a filter placed at a predetermined angle to said expanded broadband light beam for separating two or more wavelengths with a desired spacing therebetween from said expanded broadband light beam.

14. A network according to claim 13 wherein said filter comprises an etalon having a dielectric substrate with front and back sides, said front and back sides being covered with partially reflective metal or dielectric coating.

15. A network according to claim 10 wherein said modulators of all of said transceivers are powered by one or more multiple monochromatic light sources.

16. A network according to claim 9 wherein said means for generating comprises a plurality of CMOS integrated light sources.

17. A network according to claim 16 wherein said CMOS integrated light sources are VCSELs.

18. A network according to claim 1 powered by a single broadband light source.