Sir I would like to know relation between LAUNCHED POWER and receiver sensitivity. Whether receiver sensitivity and received power are same? For back to back and fiber based setup, where curve pattern will be samr or different. For dual polarization dschemes, e.g. DP-BPSK,DP-QPSK etc , I observ a linear relation. But on adding set OSNR, relation still remains linear. I am confused ,because set osnr intrroduces some noise. still linear relation? why? what should I do to improve it.
Attched image is for 80km fiber length DP-QPSK.with set osnr 11-16dB.
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