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Is this value for non linear coefficient practical?

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(joined May 2014)
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I use 100 Gb/s QPSK signal transmitted over 1000 km of SMF and the effect of non-linearity when calculating Q-factor appears at 3 dB when using non-linear coefficient n2=1e-19 ,Aeff=80 , are this parameters practical ? as the typical value of n2 around 3e-20 but it doesn’t affect the value of Q-factor (non linearity doesn’t appear).

Responses (7):

    • #20063
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      mai fouad
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      I use 100 Gb/s QPSK signal transmitted over 1000 km of SMF and the effect of non-linearity when calculating Q-factor appears at 3 dB when using non-linear coefficient n2=1e-19 ,Aeff=80 , are this parameters practical ? as the typical value of n2 around 3e-20 but it doesn’t affect the value of Q-factor (non linearity doesn’t appear).

    • #20064
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      Abdallah Ismail
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      If the units of the values that you’ve mentioned above for n2 in m2/W and for Aeff in um2
      you’ll find that gamma will be equal to 5 (1/(w.km)) and this a very large value that will affect Q factor.
      The possible reason that i think,perhaps you use a DSP component that has a phase correction algorithm (CPE) which correct the phase error due to the nonlinearity and you should disable it in the DSP.

      +1
    • #20066
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      Abhishek Shrama
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      Abdallah i have n2= 26×10^-21 and Aeff =80 then how to calculate value x/Km/W???
      What is formula to calculate Gamma??

    • #20076
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      Abhishek Shrama
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      can we take vary value of gamma arbitrarily??
      I saw it to be 1.3/km/w and 5 in some paper. can I change it ?

    • #20079
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      Abdallah Ismail
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      It is a characteristic of fiber depend on the manufacture

    • #21603
      Ajay Vyas
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      Thanking you sir
      this is very useful to solve my problem

    • #21607
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      Alessandro Festa
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      Dear Mai, you are not mentioning the launch power level into the fiber…if it is too low, Q-factor may not be affected by non-linearity.

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