Hello Jyoti Raina,
I have modified the 16 channel NRZ ideal WDM design from the library to have 4 channel at the input and find acceptable BER and Q-factor. Please have a look into this design attached herewith and respective wavelength wavelength snapshot.
The modification I have done here are following,
the transmitter output changed from 16 to 4.
deleted unnecessary blocks.
fiber centre wavelength to 1563 nm.
Dispersion compensation fiber reference wavelength to 1563 nm.
WDM demux output wavelength to the 1st two transmitted wavelength i.e. 1565 nm and 1563 nm.
Thats all.
Thanking you..
Regards,
Dhiman