I want to plot the graph between launch power per channel and required osnr at the BER of 10^-3 for advanced modulation format. for this should i use the osnr set component at the transmitter side and by varying the osnr value ,note down the BER in the BER test component or there is any other method to determine the required OSNR at the BER of 10^-3.when i use the set osnr component the BER becomes very high.
BER of 10^-3 means the exact value of 10^-3 or there is little variation like 3.2X10^-3 or any value is also acceptable.
To compare the two systems with different modulation formats wrt to osnr vs ber ,the value of the transmitter power should be same or different as the value of BER at 0 OSNR and different transmitter powers for different modulation format are different.
.