Correction table for interferometric optical signal-to-noise ratio monitor
The present disclosure includes a computer-implemented method of correcting a measured optical signal-to-noise ratio (OSNR) comprising receiving an optical signal and measuring OSNR of the optical signal using an interferometric OSNR monitor device. The method also includes applying a correction table to the measured OSNR to generate a corrected OSNR using a controller, the correction table comprising a correction function to counteract an artifact in the measured OSNR. The method also includes storing the corrected OSNR in a non-transitory computer-readable medium. The present disclosure also includes associated devices applying the correction table and methods of generating the correction table.
1. A computing processor-implemented method for generating a correction table for correcting measured optical signal-to-noise ratio (OSNR), comprising:
receiving an optical signal;
detecting, by a controller, an artifact associated with a measured OSNR of the optical signal;
calculating, by the controller, a correction function to counteract the artifact, the correction function varying over the measured OSNR; and
storing the correction function in the correction table in a non-transitory computer readable medium;
wherein OSNR can be calculated and measured based on a set of parameters (s, a) related to the power distribution and calibration factors that can have different values for different optical signal modulation schemes.
2. The method of claim 1 , further comprising:
measuring a first OSNR with a first known value; and
measuring a second OSNR with a second known value;
wherein calculating a correction function of the artifact comprises:
determining a first difference caused by the artifact between the first OSNR and the first known value; and
determining a second difference caused by the artifact between the second OSNR and the second known value.
3. The method of claim 1 , wherein the artifact comprises one of a pass-band narrowing effect, an optical filter's frequency offset, and a transmitter's frequency offset.
4. The method of claim 3 , wherein a different correction function of the correction table is generated if the artifact comprises a pass-band narrowing effect, an optical filter's frequency offset, or a transmitter's frequency offset.
5. The method of claim 1 , wherein a different correction function is generated for different bandwidths, different powers of the optical signal, and different numbers of spans of a network traversed by the optical signal.
6. The method of claim 1 , wherein the OSNR is measured using the equation:
O
S
NR
[
dB
]
=
10
×
log
[
(
(
a
+
1
)
·
(
s
-
a
)
(
P
2
P
1
-
a
)
·
(
s
+
1
)
-
a
+
1
s
+
1
)
-
1
·
B
R
]
.
7. The method of claim 1 , wherein the correction table includes corrections for OSNR from five dB to thirty-five dB.
8. The method of claim 1 , wherein the correction table corrects the measured OSNR to within 0.5 dB of an actual OSNR.
9. A computing processor-implemented method of correcting a measured optical signal-to-noise ratio (OSNR), comprising:
receiving an optical signal;
measuring OSNR of the optical signal using an interferometric OSNR monitor device; applying a correction table to the measured OSNR to generate a corrected OSNR using a controller, the correction table comprising a correction function to counteract an artifact in the measured OSNR; and
storing the corrected OSNR in a non-transitory computer-readable medium;
wherein OSNR can be calculated and measured based on a set of parameters (s, α) related to the power distribution and calibration factors that can have different values for different optical signal modulation schemes.
10. The method of claim 9 , wherein the optical signal comprises a plurality of data-carrying wavelengths, further comprising:
separating out a first data-carrying wavelength from the optical signal;
wherein the measured OSNR is measured for the first data-carrying wavelength and associated in-band noise.
11. The method of claim 10 , wherein the optical signal comprises a plurality of data-carrying polarities, further comprising:
separating out a first polarity of the first data-carrying wavelength;
wherein the measured OSNR is measured for the first polarity of the first data-carrying wavelength and associated in-band noise.
12. The method of claim 9 , wherein the artifact comprises one of a pass-band narrowing effect, an optical filter's frequency offset, and a transmitter's frequency offset.
13. The method of claim 12 , wherein a different correction function is applied if the artifact is a pass-band narrowing effect, an optical filter's frequency offset, or a transmitter's frequency offset.
14. The method of claim 9 , wherein a different correction function is applied for different bandwidths, different powers of the optical signal, and different numbers of spans of a network traversed by the optical signal.
15. The method of claim 9 , wherein the OSNR is measured using the equation:
O
S
NR
[
dB
]
=
10
×
log
[
(
(
a
+
1
)
·
(
s
-
a
)
(
P
2
P
1
-
a
)
·
(
s
+
1
)
-
a
+
1
s
+
1
)
-
1
·
B
R
]
.
16. The method of claim 9 , wherein the correction table includes corrections for OSNR from five dB to thirty-five dB.
17. The method of claim 9 , wherein the correction table corrects the measured OSNR to within 0.5 dB of an actual OSNR.
18. A device for correcting a measured optical signal-to-noise ratio (OSNR) of an optical signal, the device comprising: a monitor device configured to generate values from which OSNR of the optical signal may be measured; a controller configured to measure the OSNR of the optical signal using the values generated by the monitor device and apply a correction table to the measure OSNR to generate a corrected OSNR, the correction table comprising a correction function to counteract an artifact in the measured OSNR; and non-transitory computer readable medium to receive the corrected OSNR from the controller and store the corrected OSNR; wherein OSNR can be calculated and measured based on a set of parameters (s, a) related to the power distribution and calibration factors that can have different values for different optical signal modulation schemes.
19. The device of claim 18 , wherein the monitor device is further configured to separate out a first data-carrying wavelength from a plurality of data-carrying wavelengths in the optical signal, and the measured OSNR is measured for the first data-carrying wavelength and associated in-band noise.
20. The device of claim 19 , wherein the monitor device is further configured to separate out a first polarity from a plurality of polarities in the optical signal, and the measured OSNR is measured for the first polarity of the first data-carrying wavelength and associated in-band noise.
21. The device of claim 18 , wherein the artifact comprises one of a pass-band narrowing effect, an optical filter's frequency offset, and a transmitter's frequency offset.
22. The device of claim 21 , wherein a different correction function is applied if the artifact is a pass-band narrowing effect, an optical filter's frequency offset, or a transmitter's frequency offset.
23. The device of claim 18 , wherein a different correction function is applied for different bandwidths, different powers of the optical signal, and different numbers of spans of a network traversed by the optical signal.
24. The device of claim 18 , wherein the OSNR is measured using the equation:
O
S
NR
[
dB
]
=
10
×
log
[
(
(
a
+
1
)
·
(
s
-
a
)
(
P
2
P
1
-
a
)
·
(
s
+
1
)
-
a
+
1
s
+
1
)
-
1
·
B
R
]
.
25. The device of claim 18 , wherein the correction table includes corrections for OSNR from five dB to thirty-five dB.
26. The device of claim 18 , wherein the correction table corrects the measured OSNR to within 0.5 dB of an actual OSNR.