Hello Chetan
There are few examples in OptiSystem on OCDMA that can be found in the example library at:
C:\Users\xxxxxxx\Documents\OptiSystem 15.2 Samples\Metro and access systems\PON and CDMA systems
and
C:\Users\xxxxxxxx\Documents\OptiSystem 15.2 Samples\Software interworking\OptiGrating
You may use the base design to example to 5 users.
Which OptiSystem version are you using?
Regards,
Ahmad