Effect of Input power on Q factor and BER

[Ahmad MustafaParticipant]

Hi,

Can anybody explain the effect of optical input power on the Q factor and BER. I do not see any effect on these two parameters as I increase the input power of my laser. The Eye height gets affected linearly however.

Thanks

[Damian MarekParticipant]

I moved this to the System section, because the Knowledge section is reserved for moderators.

Generally the BER should improve as the input power is increased. However, there is a point at which nonlinear effects will significantly degrade the signal. On another note, perhaps the change in BER is very small. To resolve the small change try increasing the sequence length, which will increase the accuracy of the BER calculation.

[PATEL BHUMITKUMAR PRAHLADBHAIParticipant]

Dear,

As power increase, non linearity increase and that will decrease the performance of the system.

But from the results i got that as power increase up to certain level, Q factor increase but after that Q downs because non linearity dominates.

[ANKITParticipant]

As such, there is no direct relation of input power with the BER and Q value, but still if you go on increasing the input power up to certain limit, the Q value gets increased and BER get decreased. But when you increase the input power, nonlinearities will knock your door. I verified this with 1.28 Tbps DWDM network.

Good luck.

Ankit

[Ahmad MustafaParticipant]

Thanks all