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What is OSNR-Optical Signal to Noise Ratio

This page explains basics of OSNR (Optical Signal to Noise Ratio). It mentions OPS method to measure OSNR.

OSNR is the short form of Optical Signal to Noise Ratio. It is key parameter to estimate peformance of Optical Networks. It helps in BER calculation of Optical System.

As per linear interpolation method, to measure OSNR following steps are followed:
• First Measure total Signal power in passband channel.
• Measure noise power i.e. ASE noise within the gaps between optical channels. It will have 0.1 nm of bandwidth usually.
• Now use equation mentioned below to calculate OSNR value.


OSNR measurement

Figure-1 depicts OSNR measurement with signal of interest and undesired noise power on left and right side of wanted optical signal. OSNR is expressed using following equation:
OSNR = PSIGNAL/( (PNoise(L) + PNoise(R))/2)

OPS Method to Measure OSNR

OPS stands for Optical Polarization Splitting Method. It is used to measure in-band OSNR type. It uses optical polarization controlling and splitting. Figure-2 below mentions block diagram of the OPS method used by JSDU.


OPS method to measure OSNR

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