Hello,
I am studying the impact of fiber nonlinearity in CO-OFDM system. I wonder whether the level of fiber nonlinear impact depends on modulation index or not. I assume that the OFDM signal swing totally fall in linear area of MZM, but I am not sure if the impact of fiber nonllinearity only reply on launch power just before going to the fibre, or also depends on modulation index although signal peak to peak is on the linear region of MZM.
I saw some examples with OFDM, and the common characteristic of all OFDM signal in these examples is that there is an amplifier before MZM with the very small coefficient (0.008, for example), it make the OFDM swing is really small compare to linear region of MZM ( let say 0 to 5, for example).
Someone can advise on my concern? thank you
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