Tunable optical channel slicing and stitching to enable dynamic bandwidth allocation

Patent metadata

Field	Value
Publication number	US-10277326-B2
Application number	US-201815890211-A
Country	US
Kind code	B2
Filing date	Feb 6, 2018
Priority date	Feb 8, 2017
Publication date	Apr 30, 2019
Grant date	Apr 30, 2019

Abstract

A method for transmitting an optical signal through a first channel and a second channel includes coupling the optical signal with a first pair of comb lines separated by a spacing frequency to create an optical signal copy that is spaced from the optical signal by the spacing frequency. The method also includes filtering a first slice of the optical signal and a second slice of the optical signal copy. The method also includes transmitting the first slice of the optical signal and the second slice of the optical signal through the first channel and the second channel, respectively. The method also includes stitching the first slice of the optical signal with the second slice of the optical signal copy to generate a stitched version of the original optical signal.

First claim

What is claimed is:

1. A method for transmitting an optical signal through a first channel to take a first portion of the optical signal and a second channel to take a second portion of the optical signal, the first channel and the second channel being separated by a spacing frequency, the method comprising:
generating multiple comb lines from a comb source;
selecting, using a filter, a first pair of spacing coherent optical frequency comb lines from the multiple comb lines;
nonlinearly mixing the optical signal with the first pair of spacing coherent optical frequency comb lines separated by the spacing frequency to create an optical signal copy that is spaced from the optical signal by the spacing frequency;
filtering a first slice of the optical signal and a second slice of the optical signal copy, the first slice representing a first portion of the optical signal and the second slice representing a second complementary portion of the optical signal;
transmitting the first slice of the optical signal and the second slice of the optical signal through the first channel and the second channel, respectively; and
using nonlinear mixing to combine the first slice of the optical signal with the second slice of the optical signal copy with a second pair of spacing coherent optical frequency comb lines separated by the spacing frequency to recover the optical signal.

2. The method of claim 1 further comprising amplifying the optical signal prior to nonlinearly mixing the optical signal with the first pair of spacing coherent optical frequency comb lines.

3. The method of claim 1 wherein the filter includes a first spatial light modulator.

4. The method of claim 1 wherein nonlinearly mixing the optical signal with the first pair of spacing coherent optical frequency comb lines to create the optical signal copy includes passing the optical signal and the first pair of spacing coherent optical frequency comb lines through a first periodically poled lithium niobate waveguide having a quasi-phase matching wavelength such that a phase of the optical signal is preserved in the optical signal copy.

5. The method of claim 1 wherein filtering the first slice of the optical signal and the second slice of the optical signal copy includes tuning a phase offset between the first slice of the optical signal and the second slice of the optical signal copy based on a desire for the first slice and the second slice to be constructively combined.

6. The method of claim 1 further comprising inserting the first slice of the optical signal and the second slice of the optical signal copy to multiple signal channels for co-transmission prior to using the nonlinear mixing to combine the first slice of the optical signal with the second slice of the optical signal copy.

7. The method of claim 1 wherein using the nonlinear mixing to combine the first slice of the optical signal with the second slice of the optical signal copy includes amplifying the first slice of the optical signal with the second slice of the optical signal copy together with the first pair of spacing coherent optical frequency comb lines.

8. The method of claim 1 wherein using the nonlinear mixing to combine the first slice of the optical signal with the second slice of the optical signal copy further includes passing the separate two slices and the second pair of spacing coherent optical frequency comb lines through a second periodically poled lithium niobate waveguide having a quasi-phase matching wavelength.

9. The method of claim 1 further comprising transmitting the first slice of the optical signal through the first channel and transmitting the second slice of the optical signal copy through the second channel prior to using the nonlinear mixing to combine the first slice of the optical signal with the second slice of the optical signal copy.

10. A method for transmitting a first portion of an optical signal and a second portion of the optical signal through a first channel and a second channel, respectively, the method comprising:
generating multiple comb lines using a comb source;
selecting, using a filter, a first pair of spacing coherent optical frequency comb lines from the multiple comb lines;
identifying, at a transmitter, at least two available channels in an available optical spectrum each having an available bandwidth;
receiving, at the transmitter, a request for a new optical signal having a signal bandwidth that is greater than the available bandwidth of either of the at least two available channels;
nonlinearly mixing the new optical signal with the first pair of spacing coherent optical frequency comb lines separated by the spacing frequency to create an optical signal copy that is spaced from the new optical signal by the spacing frequency;
filtering a first slice of the new optical signal and a second slice of the optical signal copy, the first slice representing a first portion of the new optical signal and the second slice representing a second complementary portion of the new optical signal;
transmitting, by the transmitter, the at least two signal slices to a receiver via a first channel and a second channel;
receiving, by a receiver, the at least two signal slices; and
using nonlinear mixing, at the receiver, to combine the at least two signal slices to recover the new optical signal.

11. The method of claim 10 further comprising:
identifying, at the transmitter, a spacing frequency between each of the at least two available channels;
transmitting, by the transmitter, the spacing frequency to the receiver; and
receiving, by the receiver, the spacing frequency, wherein using the nonlinear mixing to combine the at least two signal slices includes using the nonlinear mixing to combine the at least two signal slices further based on the spacing frequency.

12. The method of claim 10 wherein using the nonlinear mixing to combine the at least two signal slices includes comb-based wavelength conversion using similar comb lines as the pair of spacing coherent optical frequency comb lines.

13. The method of claim 10 further comprising performing channel equalization to reduce inter-symbol-interference of the recovered new optical signal.

14. A system for transmitting an optical signal, comprising:
a transmitter having a comb source configured to generate multiple comb lines and a filter configured to select a first pair of spacing coherent optical frequency comb lines from the multiple comb lines, the transmitter being configured to:
identify at least two available channels in an available optical spectrum each having an available bandwidth,
receive a request for a new optical signal having a signal bandwidth that is greater than the available bandwidth of either of the at least two available channels,
nonlinearly mix the new optical signal with the first pair of spacing coherent optical frequency comb lines separated by the spacing frequency to create an optical signal copy that is spaced from the new optical signal by the spacing frequency,
filter a first slice of the new optical signal and a second slice of the optical signal copy, the first slice representing a first portion of the new optical signal and the second slice representing a second complementary portion of the new optical signal, and
transmit the at least two signal slices onto an optical transmission line; and

a receiver configured to:
receive the at least two signal slices via the optical transmission line, and
use nonlinear mixing to combine the at least two signal slices to recover the new optical signal.

15. The system of claim 14 wherein:
the transmit

Assignees

• Univ Southern California

Inventors

• Cao Yinwen
• Willner Alan

Classifications

• H04B10/572

  Wavelength control · CPC title

• H04B10/2507

  for the reduction or elimination of distortion or dispersion · CPC title

• H04J14/0298

  with sub-carrier multiplexing [SCM] · CPC title

• H04J14/0265 Primary

  Multiplex arrangements in bidirectional systems, e.g. interleaved allocation of wavelengths or allocation of wavelength groups · CPC title

• H04B10/506 Primary

  Multiwavelength transmitters · CPC title