Method and apparatus for interdependent control of amplification and switching state in a photonic switch

Patent metadata

Field	Value
Publication number	US-11095509-B2
Application number	US-201916567343-A
Country	US
Kind code	B2
Filing date	Sep 11, 2019
Priority date	Sep 11, 2019
Publication date	Aug 17, 2021
Grant date	Aug 17, 2021

Abstract

A method and apparatus for controlling an optical switch. The switch includes a switching fabric and optical amplifiers for amplifying optical signals. A configuration for the switching fabric is generated and implemented. The configuration indicates a set of optical paths between switching fabric input ports and the output ports. Optical path losses through the switching fabric vary based on the configuration. An amplifier control signal for controlling gains of the optical amplifiers, is also provided. The configuration for the switching fabric is generated based on the gains of the optical amplifiers, the amplifier control signal is generated based on the configuration for the switching fabric, or both.

First claim

What is claimed is:

1. A controller for an optical switch, the optical switch comprising a switching fabric controllable to route optical signals from input ports to output ports, and one or more optical amplifiers for amplifying one or more of said optical signals, the controller comprising processing electronics and a control output, and configured to:
generate a configuration for the switching fabric, the configuration indicating a selected set of optical paths between the input ports and the output ports, wherein optical path losses through the switching fabric vary based on the configuration;
provide, at the control output, a switching fabric control signal for implementing the configuration for the switching fabric; and
generate and provide, at the control output, an amplifier control signal for controlling gains of the one or more optical amplifiers, to cause the gains to be above a lower gain threshold and below an upper gain threshold;
wherein the configuration for the switching fabric is generated based at least in part on the gains of the one or more optical amplifiers, the amplifier control signal is generated based on the configuration for the switching fabric, or both;
wherein the amplifier control signal is generated based at least in part on optical specifications of a transceiver operatively coupled to the optical switch;
wherein for each one of the optical signals, the transceiver has a corresponding optical bandwidth wider than a bandwidth of said one of the optical signals;
wherein the lower gain threshold is configured so that causing the gains to be above the lower gain threshold results in the amplified optical signals being sufficiently strong that a bit error rate of the transceiver is below a first bit error rate threshold; and
wherein the upper gain threshold is configured so that causing the gains to be below the upper gain threshold results in amplified spontaneous emission (ASE) noise of the optical amplifiers being sufficiently low that the bit error rate is below a second the bit error rate threshold.

2. The controller of claim 1 , wherein generating the amplifier control signal comprises:
maintaining a prior amplifier control signal as the amplifier control signal when applying the prior amplifier control signal along with the configuration for the switching fabric results in a path loss for the optical switch being below a predetermined threshold, and updating the amplifier control signal otherwise, wherein the prior amplifier control signal controls gains of the one or more optical amplifiers during implementation of a prior configuration for the switching fabric, the prior configuration being immediately prior to the configuration for the switching fabric.

3. The controller of claim 1 , wherein the configuration for the switching fabric is generated independently of the gains of the one or more optical amplifiers and the amplifier control signal is generated based on the configuration for the switching fabric.

4. The controller of claim 1 , wherein the configuration for the switching fabric is generated based at least in part on the gains of the one or more optical amplifiers.

5. The controller of claim 4 , further configured to select the configuration for the switching fabric to avoid or limit a requirement to change the gains of the one or more optical amplifiers, said requirement being necessary to maintain a predetermined performance level for the optical switch.

6. The controller of claim 1 , wherein generating the configuration for the switching fabric and generating the amplifier control signal is based on a requirement to maintain a predetermined performance metric for the optical switch.

7. The controller of claim 6 , wherein the performance metric includes one or more of: the bit error rate being below the first bit error rate threshold; an optical signal level being above a first specified threshold; an optical signal to noise ratio being above a second specified threshold; and an optical path loss being below a third specified threshold.

8. The controller of claim 1 , wherein the optical amplifiers are semiconductor optical amplifiers.

9. The controller of claim 1 , wherein the optical amplifiers are wideband, unfiltered amplifiers.

10. The controller of claim 1 , wherein the configuration for the switching fabric, the amplifier control signal, or both, are generated based at least in part on one or more of: link budget requirements; communication system performance requirements; optical specifications of the switch; and optical specifications of optical components coupled to the switch.

11. A method for controlling an optical switch, the optical switch comprising a switching fabric controllable to route optical signals from input ports to output ports, and one or more optical amplifiers for amplifying one or more of said optical signals, the method comprising:
generating a configuration for the switching fabric, the configuration indicating a selected set of optical paths between the input ports and the output ports, wherein optical path losses through the switching fabric vary based on the configuration;
providing a switching fabric control signal for implementing the configuration for the switching fabric; and
generating and providing an amplifier control signal for controlling gains of the one or more optical amplifiers, to cause the gains to be above a lower gain threshold and below an upper gain threshold,
wherein the configuration for the switching fabric is generated based at least in part on the gains of the one or more optical amplifiers, the amplifier control signal is generated based on the configuration for the switching fabric, or both;
wherein the amplifier control signal is generated based at least in part on optical specifications of a transceiver operatively coupled to the optical switch;
wherein the transceiver has an optical bandwidth wider than a bandwidth of all of said optical signals in combination;
wherein the lower gain threshold is configured so that causing the gains to be above the lower gain threshold results in the amplified optical signals being sufficiently strong that a bit error rate of the transceiver is below a first bit error rate threshold; and
wherein the upper gain threshold is configured so that causing the gains to be below the upper gain threshold results in amplified spontaneous emission (ASE) noise of the optical amplifiers being sufficiently low that the bit error rate is below the bit error rate threshold.

12. The method of claim 11 , wherein generating the amplifier control signal comprises:
maintaining a prior amplifier control signal as the amplifier control signal when applying the prior amplifier control signal along with the configuration for the switching fabric results in a path loss for the optical switch being below a predetermined threshold, and updating the amplifier control signal otherwise, wherein the prior amplifier control signal controls gains of the one or more optical amplifiers during implementation of a prior configuration for the switching fabric, the prior configuration being immediately prior to the configuration for the switching fabric.

13. The method of claim 11 , wherein the configuration for the switching fabric is generated independently of the gains of the one or more optical amplifiers and the amplifier control signal is generated based on the configuration for the switching fabric.

14. The method of claim 11 , wherein the configuration for the switching fabric is generated based at least in part on the gains of the one or more optical amplifiers.

15. The method of claim 14 , furt

Assignees

• Mansouri Rad Mohammad Mehdi
• Huawei Tech Co Ltd

Inventors

• Mansouri Rad Mohammad Mehdi

Classifications

• H04B10/293 Primary

  Signal power control · CPC title

• H04L43/0847

  Transmission error · CPC title

• H04B10/07953

  Monitoring or measuring OSNR, BER or Q · CPC title

• H04L41/0816 Primary

  the condition being an adaptation, e.g. in response to network events · CPC title

• H04Q2011/005

  Arbitration and scheduling · CPC title