Here is a good example of CSP at work. Imagine two BPSK signals with different symbol rates and slightly different center frequencies. Looking at the combined BPSK signals - created with mksig.py -d, ...
Subscribe here to receive similar articles over e-mail whenever Krishna Pillai publishes an article on his site. The article compares various digital modulation schemes like BPSK, QPSK, PAM, 16PSK, ...