Power Control in an Optical Fiber Network

Patent metadata

Field	Value
Publication number	US-2018343078-A1
Application number	US-201715796393-A
Country	US
Kind code	A1
Filing date	Oct 27, 2017
Priority date	May 24, 2017
Publication date	Nov 29, 2018
Grant date	—

Abstract

Multiple receivers are comprised in a flexible coherent transceiver of a multi-span optical fiber network. Each of the multiple receivers is operative to handle communications on a respective channel. The multiple receivers measure optical characteristics. For each of the multiple receivers, the optical characteristics include optical nonlinear interactions on the respective channel, the optical nonlinear interactions being at least partially dependent from one span to another span. An optical power of a signal on each of the multiple channels is adjusted as a function of the optical characteristics.

First claim

What is claimed is:

1 . A method of power control in a multi-span optical fiber network, the method comprising:
measuring optical characteristics in multiple receivers comprised in a flexible coherent transceiver of the multi-span optical fiber network, each of the multiple receivers operative to handle communications on a respective channel; and adjusting an optical power of a signal on each of the multiple channels as a function of the optical characteristics, wherein for each of the multiple receivers, the optical characteristics include optical nonlinear interactions on the respective channel, the optical nonlinear interactions being at least partially dependent from one span to another span.

2 . The method as recited in claim 1 , wherein for each of the multiple receivers, the optical characteristics include accumulated cross-phase modulation on the respective channel due to other channels.

3 . The method as recited in claim 1 , wherein for each of the multiple receivers, the optical characteristics include accumulated self-phase modulation on the respective channel.

4 . The method as recited in claim 1 , wherein for each of the multiple receivers, the optical characteristics include accumulated amplified spontaneous emission on the respective channel.

5 . The method as recited in claim 1 , wherein the optical power that is adjusted is the optical launch power.

6 . The method as recited in claim 1 , wherein adjusting the optical power includes adjusting loss values of a wavelength selective switch (WSS) component.

7 . The method as recited in claim 1 , wherein adjusting the optical power includes adjusting a total launch power.

8 . The method as recited in claim 1 , wherein adjusting the optical power includes adjusting a target total optical power or a target gain of an optical pre-amplifier device comprised in another flexible coherent transceiver of the multi-span optical fiber network.

9 . The method as recited in claim 1 , wherein adjusting the optical power includes adjusting a total received power at the flexible coherent transceiver.

10 . The method as recited in claim 1 , wherein adjusting the optical power includes adjusting a common target total optical power or a fixed target gain of multiple optical amplifier devices in the multi-span optical fiber network.

11 . The method as recited in claim 1 , wherein adjusting the optical power is a bounded step change.

12 . The method as recited in claim 11 , wherein adjusting the optical power includes:
using measurements of the optical characteristics to evaluate gradients of an objective function; and determining a direction of the bounded step change from one or more dimensions of the gradients.

13 . The method as recited in claim 12 , wherein the objective function incorporates a value function of margin determined by the multiple receivers.

14 . The method as recited in claim 13 , wherein the value function is a concave value function.

15 . An apparatus comprising:
a processor configured to receive measurements of optical characteristics from a flexible coherent transceiver of a multi-span optical fiber network, the measurements of optical characteristics having been measured in multiple receivers comprised in the flexible coherent transceiver, each of the multiple receivers operative to handle communications on a respective channel, the processor configured to apply a control algorithm that adjusts an optical power of a signal on each of the multiple channels as a function of the optical characteristics, wherein for each of the multiple receivers, the optical characteristics include optical nonlinear interactions on the respective channel, the optical nonlinear interactions being at least partially dependent from one span to another span.

16 . The apparatus as recited in claim 15 , wherein for each of the multiple receivers, the optical characteristics include accumulated cross-phase modulation on the respective channel due to other channels.

17 . The apparatus as recited in claim 15 , wherein for each of the multiple receivers, the optical characteristics include accumulated self-phase modulation on the respective channel.

18 . The apparatus as recited in claim 15 , wherein the optical power that is adjusted is the optical launch power.

19 . The apparatus as recited in claim 15 , wherein the control algorithm adjusts the optical power by adjusting a total launch power.

20 . The apparatus as recited in claim 15 , wherein the control algorithm adjusts the optical power by adjusting a total received power at the flexible coherent transceiver.

Assignees

• Roberts Kim B
• Harley James
• Zhuge Qunbi
• Reimer Michael Andrew
• Osullivan Maurice
• Ciena Corp

Inventors

• Roberts Kim B
• Harley James
• Zhuge Qunbi
• Reimer Michael Andrew
• O'Sullivan Maurice

Classifications

• H04B10/2935

  with a cascade of amplifiers · CPC title

• H04B10/2941

  using an equalising unit, e.g. a filter (H04B10/296 takes precedence) · CPC title

• H04B10/2537

  due to scattering processes, e.g. Raman or Brillouin scattering · CPC title

• H04B10/0795

  Performance monitoring; Measurement of transmission parameters · CPC title

• H04B10/07953

  Monitoring or measuring OSNR, BER or Q · CPC title