Methods, Systems and Devices for Optical-Signal-to-Noise-Ratio Monitoring

Patent metadata

Field	Value
Publication number	US-2016142133-A1
Application number	US-201414221124-A
Country	US
Kind code	A1
Filing date	Mar 20, 2014
Priority date	Mar 20, 2013
Publication date	May 19, 2016
Grant date	—

Abstract

A device for optical-signal-to-noise (OSNR) monitoring can include: a delay-line interferometer configured to connect with a tunable optical filter; and two or more power detectors to measure outputs of the interferometer; wherein one or more parameters are optimized for different transmission baud rates to improve accuracy. In addition, a method can include: connecting an input of a delay-line interferometer with an output of a tunable optical filter, and an output of the delay-line interferometer with an input of a power detector, to form an optical-signal-to-noise (OSNR) monitoring apparatus; optimizing one or more parameters of the OSNR monitoring apparatus for different transmission baud rates to improve accuracy.

First claim

What is claimed is:

1 . A device for optical-signal-to-noise (OSNR) monitoring, the device comprising:
a delay-line interferometer configured to connect with a tunable optical filter; and two or more power detectors to measure outputs of the interferometer; wherein one or more parameters are optimized for different transmission baud rates to improve accuracy.

2 . The device of claim 1 , wherein a delay value of the delay-line interferometer is optimized based on phase fluctuations, a monitored channel, and a center frequency for the monitored channel.

3 . The device of claim 2 , wherein a voltage of the delay-line interferometer is tuned so that a power difference between constructive and destructive ports is maximized.

4 . The device of claim 3 , wherein filter bandwidth and filter shape are optimized.

5 . The device of claim 4 , wherein the device is capable of achieving <0.5 dB error for signals with <22 dB actual OSNR.

6 . The device of claim 5 , configured to measure OSNR on high-bit-rate pol-muxed QPSK and QAM data in WDM channels.

7 . The device of claim 6 , configured to measure OSNR based on (i) measured power at a constructive port, (ii) measured power at a destructive port, (iii) a ratio between the measured power at the constructive port and the measured power at the destructive port, and (iv) a noise distribution ratio for a case when only ASE (Amplified Spontaneous Emission) noise is transmitted.

8 . The device of claim 1 , wherein a voltage of the delay-line interferometer is tuned so that a power difference between constructive and destructive ports is maximized.

9 . The device of claim 8 , wherein filter bandwidth and filter shape are optimized.

10 . The device of claim 8 , configured to measure OSNR based on (i) measured power at a constructive port, (ii) measured power at a destructive port, (iii) a ratio between the measured power at the constructive port and the measured power at the destructive port, and (iv) a noise distribution ratio for a case when only ASE (Amplified Spontaneous Emission) noise is transmitted.

11 . The device of claim 1 , wherein filter bandwidth and filter shape are optimized.

12 . The device of claim 11 , wherein the device is capable of achieving <0.5 dB error for signals with <22 dB actual OSNR.

13 . The device of claim 11 , configured to measure OSNR based on (i) measured power at a constructive port, (ii) measured power at a destructive port, (iii) a ratio between the measured power at the constructive port and the measured power at the destructive port, and (iv) a noise distribution ratio for a case when only ASE (Amplified Spontaneous Emission) noise is transmitted.

14 . The device of claim 1 , configured to measure OSNR on high-bit-rate pol-muxed QPSK and QAM data in WDM channels, wherein the device is capable of achieving <0.5 dB error for signals with <22 dB actual OSNR.

15 . The device of claim 1 , configured to measure OSNR based on (i) measured power at a constructive port, (ii) measured power at a destructive port, (iii) a ratio between the measured power at the constructive port and the measured power at the destructive port, and (iv) a noise distribution ratio for a case when only ASE (Amplified Spontaneous Emission) noise is transmitted.

16 . A method comprising:
connecting an input of a delay-line interferometer with an output of a tunable optical filter, and an output of the delay-line interferometer with an input of a power detector, to form an optical-signal-to-noise (OSNR) monitoring apparatus; optimizing one or more parameters of the OSNR monitoring apparatus for different transmission baud rates to improve accuracy.

17 . The method of claim 16 , wherein the optimizing comprises optimizing a delay value of the delay-line interferometer based on phase fluctuations, a monitored channel, and a center frequency for the monitored channel.

18 . The method of claim 16 , wherein the optimizing comprises tuning a voltage of the delay-line interferometer so that a power difference between constructive and destructive ports is maximized.

19 . The method of claim 16 , wherein the optimizing comprises optimizing filter bandwidth and filter shape.

20 . The method of claim 16 , comprising measuring OSNR based on (i) measured power at a constructive port, (ii) measured power at a destructive port, (iii) a ratio between the measured power at the constructive port and the measured power at the destructive port, and (iv) a noise distribution ratio for a case when only ASE (Amplified Spontaneous Emission) noise is transmitted.

Assignees

• Univ Southern California

Inventors

• Chitgarha Mohammad Reza
• Khaleghi Salman
• Almaiman Ahmed
• Willner Alan E

Classifications

• H04J14/0227

  Operation, administration, maintenance or provisioning [OAMP] of WDM networks, e.g. media access, routing or wavelength allocation · CPC title

• H04B10/07953 Primary

  Monitoring or measuring OSNR, BER or Q · CPC title