System and method for determining nonlinear mitigation perturbative distortion coefficients using a received optical signal

Patent metadata

Field	Value
Publication number	US-9906309-B2
Application number	US-201514675187-A
Country	US
Kind code	B2
Filing date	Mar 31, 2015
Priority date	Mar 31, 2015
Publication date	Feb 27, 2018
Grant date	Feb 27, 2018

Abstract

A processor circuit is provided in a coherent optical receiver module. The processor receives a series of electrical signals over a time period, representative of a series of optical signals received at instants of time within the time period. Each of the electrical signals is indicative of a respective one of a plurality of points on an IQ plane, each of the points being spaced from one of a plurality of predetermined points in the IQ plane by a corresponding one of a plurality of distortion values. In addition, the processor circuit calculates one or more perturbative coefficients based on one or more of the distortion values and determines data from the series of electrical signals based on the perturbative coefficient.

First claim

What is claimed is:

1. A method, comprising:
receiving a series of optical signals with a coherent optical receiver module;
generating a series of electrical signals in response to the received optical signals;
receiving, with a processor circuit in the coherent optical receiver module, a series of electrical signals over a time period, representative of the series of optical signals received at instants of time within the time period, each of the electrical signals being indicative of a respective one of a plurality of points on an IQ plane, each of the points corresponding to a respective one of the series of optical signals and being spaced from a respective one of a plurality of predetermined points in the IQ plane by a corresponding one of a plurality of distortion values;
calculating, with the processor circuit, perturbative coefficients, c m,n px ; and
determining, with the processor circuit, data from at least one of the series of electrical signals based on the perturbative coefficient, wherein the perturbative coefficients, c m,n px , satisfies:

c

m
,
n

px

=

1
T

⁢

∑

t
=
0

T
-
1

⁢

Δ
⁢

⁢

u

t
,
x

A

n
,
p

⁢

A

m
+
n

,
p

*

⁢

A

m
,
x

where p is a polarization of the optical signals,
where m denotes a moving forward in time,
where n denotes a moving backward in time,
where T is a number of the series of electrical signals averaged, and
where t is Δu t,x is at a particular point of time, and
where Δu t,x is one of the plurality of distortion values.

2. The method of claim 1 , wherein prior to determining the data from the series of electrical signals based on the perturbative coefficient, the method comprises determining, with the processor circuit, nonlinear offsets based on the perturbative coefficient, and wherein determining the data from the series of electrical signals is based on the nonlinear offsets based on the perturbative coefficient.

3. The method of claim 1 , wherein determining the data further comprises modifying the data to conform to the predetermined points.

4. The method of claim 1 , wherein determining the data occurs before correction of the data with Forward Error Correction.

5. The method of claim 1 , wherein determining the data occurs after correction of the data with Forward Error Correction.

6. The method of claim 1 , wherein calculating, with the processor circuit, further comprises using least mean squares techniques applied to a determination of the distortion value over the time period.

7. A coherent optical receiver module comprising:
a plurality of photodiodes that receive a series of optical signals and generate a series of electrical signals; and
one or more processor circuits configured to:
receive the series of electrical signals over a time period, representative of a series of optical signals received at instants of time within the time period, each of the electrical signals being indicative of a respective one of a plurality of points on an IQ plane, corresponding to a respective one of the series of optical signals and each of the points being spaced from one of a plurality of predetermined points in the IQ plane by a corresponding one of a plurality of distortion values;
calculate perturbative coefficients, c m,n px ; and

determine data from at least one of the series of electrical signals based on the perturbative coefficient, wherein the perturbative coefficients, c m,n px , satisfy:

c

m
,
n

px

=

1
T

⁢

∑

t
=
0

T
-
1

⁢

Δ
⁢

⁢

u

t
,
x

A

n
,
p

⁢

A

m
+
n

,
p

*

⁢

A

m
,
x

where p is a polarization of the optical signals,
where m denotes a moving forward in time,
where n denotes a moving backward in time,
where T is a number of the series o

Assignees

• Infinera Corp
• Infinera Corp

Inventors

• Mertz Pierre Herve
• Karar Abdullah
• Awadalla Ahmed

Classifications

• H04B10/6163 Primary

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