owh..i see...tq GaoMing....
if u dont mind i would like to ask u come question. hopefuly u can help me...
1) what is the function of the real-imaginary to complex and complex to Real-imaginary in this operation.
2) why there is some noise at the output from scope after u put the RRC filter? i only can get a good QPSK signal if i remove the RRC filter.
3) why after we put the RRC filter, the scatter plot change being distribute?
4) what is the different between eye diagram of Q and I? or it is same between I and Q?