Dear Babar,
Attached is a block diagram that would help you working on SSB-SC modulation. You need to use the example library of OptiSystem for more information on how to create the PAM4 and QAM signals. The modulation in the block diagram is NRZ. You may find OptiSystem examples at the following link.
C:\Users\USER NAME\Documents\OptiSystem 16.1 Samples\Advanced modulation systems
regards,
Ahmad
