Conformance testing method and apparatus, and storage medium

Patent metadata

Field	Value
Publication number	US-11764871-B2
Application number	US-202217709036-A
Country	US
Kind code	B2
Filing date	Mar 30, 2022
Priority date	Apr 27, 2018
Publication date	Sep 19, 2023
Grant date	Sep 19, 2023

Abstract

A conformance testing method including: obtaining a testing symbol pattern in an optical signal; performing equalization compensation on the testing symbol pattern; generating a testing eye pattern; calculating a value of a first parameter based on the testing eye pattern and a noise enhancement coefficient, where the first parameter is used to determine a transmitter dispersion eye pattern closure degree of the optical transmitter; and when the value of the first parameter is less than or equal to a preset threshold, determining that conformance testing on the optical signal succeeds.

First claim

What is claimed is:

1. A transmitter dispersion eye pattern closure degree testing method, comprising:
obtaining, from an optical transmitter, a testing symbol pattern in an optical signal;
performing equalization compensation on the testing symbol pattern to obtain an equalized testing symbol pattern;
generating a testing eye pattern through composition using the equalized testing symbol pattern; and
calculating, based on the testing eye pattern and a noise enhancement coefficient that corresponds to the equalization compensation, a value of a first parameter, wherein the first parameter is for determining a transmitter dispersion eye pattern closure degree of the optical transmitter.

2. The transmitter dispersion eye pattern closure degree testing method of claim 1 , wherein conformance testing on the optical transmitter succeeds when the optical signal is transmitted by the optical transmitter under highest relative intensity noise and the value of the first parameter is less than or equal to a preset threshold.

3. The transmitter dispersion eye pattern closure degree testing method of claim 1 , wherein calculating the value of the first parameter comprises:
constructing, based on the testing eye pattern, a first histogram of a first sampling window, a second histogram of a second sampling window, a third histogram of a third sampling window, and a fourth histogram of a fourth sampling window, wherein the first sampling window and the second sampling window are vertically symmetrically distributed on a left part of the testing eye pattern, and wherein the third sampling window and the fourth sampling window are vertically symmetrically distributed on a right part of the testing eye pattern;
determining a first standard deviation based on the first histogram, the second histogram, the third histogram, the fourth histogram, and the noise enhancement coefficient, wherein the first standard deviation is a smaller value in a second standard deviation and a third standard deviation, wherein the second standard deviation is of a second highest additive noise that can be supported by the optical transmitter when the first sampling window and the second sampling window reach a target bit error rate, and wherein the third standard deviation is of a third highest additive noise that can be supported by the optical transmitter when the third sampling window and the fourth sampling window reach the target bit error rate;
determining, based on the first standard deviation, a standard deviation of a first highest additive noise that can be supported by the optical transmitter when the target bit error rate is reached; and
determining the value of the first parameter based on the standard deviation of the first highest additive noise.

4. The transmitter dispersion eye pattern closure degree testing method of claim 3 , wherein determining the first standard deviation comprises:
determining the second standard deviation based on the first histogram, the second histogram, and the noise enhancement coefficient;
determining the third standard deviation based on the third histogram, the fourth histogram, and the noise enhancement coefficient; and
using the smaller value in the second standard deviation and the third standard deviation as the first standard deviation.

5. The transmitter dispersion eye pattern closure degree testing method of claim 4 , wherein all sampling points in the first sampling window are located on an upper eyelid on the testing eye pattern and are higher than an average optical power of the testing eye pattern, wherein all sampling points in the second sampling window are located on a lower eyelid on the testing eye pattern and are lower than the average optical power of the testing eye pattern, and wherein determining the second standard deviation comprises:
determining a first histogram distribution function of the first sampling window based on the first histogram;
determining a second histogram distribution function of the second sampling window based on the second histogram; and
determining the second standard deviation based on the first histogram distribution function, the second histogram distribution function, the target bit error rate, and a normal distribution curve function, wherein the normal distribution curve function is based on the noise enhancement coefficient, the average optical power of the testing eye pattern, and the second standard deviation.

6. The transmitter dispersion eye pattern closure degree testing method of claim 5 , further comprising determining the normal distribution curve function according to a formula comprising:

Q
⁡

(
x
)

=

∫
x
∞

⁢

(

-

z
2

/
2

)

2
⁢
π

⁢
d
⁢
z

,

wherein Q(x) is the normal distribution curve function, wherein

x
=

y
-

p

a
⁢
v
⁢
e

C

e
⁢
q

·

σ
L

,

wherein y is an independent variable of x, wherein a value range of y is an interval between a largest value and a smallest value in optical power values corresponding to the sampling points in the first sampling window and the second sampling window, wherein P ave is the average optical power of the testing eye pattern, wherein σ L is the second standard deviation, wherein C eq is the noise enhancement coefficient, and wherein z is an integral variable of the normal distribution curve function.

7. The transmitter dispersion eye pattern closure degree testing method of claim 6 , wherein determining the second standard deviation comprises determining, through numerical simulation, that the second standard deviation meets a first formula comprising:

Assignees

• Huawei Tech Co Ltd

Inventors

• Zheng Jianyu
• Li Shengping
• Yang Ting

Classifications

• H04B10/0795 Primary

  Performance monitoring; Measurement of transmission parameters · CPC title

• H04B10/0799 Primary

  Monitoring line transmitter or line receiver equipment · CPC title

• H04B10/541

  Digital intensity or amplitude modulation · CPC title

• H04B10/6161

  Compensation of chromatic dispersion · CPC title

• H04B10/6971

  using equalisation · CPC title