try this code
OutputPort1.Sampled.Signal=InputPort1.Sampled.Signal;
[OutputPort1 = InputPort1;] delete this not need
[y=OutputPort1.Sampled.Signal;] what the value of y ,you must define this in optisystem or define here in matlab as y=10
OutputPort1.Sampled.Signal=InputPort1.Sampled.Signal+1;
what the meaning of code stage no. 3 and 4
