I'm confused by raised-cosine-rolloff function. If the received signal is BPSK, whose symbol-shaped pulse is rectangular, what the matched filter should be? Thanks for your attention!
In the case of rectanguar shaped pulse (in time domain), the shape doesn'n respond to a raised-cosine function (in frequency domain).
If symbol shape is rectangular in time then the spectrum is a sinc function in frequency. In this case, the matched filter (in baseband) has rectangular impulse response in time domain. It is frequently implemented as an integrate-and-dump circuit.
regards