Question: The description given above of the process in Figure for recovery of the transmitted message assures that the transmitter and receiver have access to a common clock (so that each may generate the function coswet). The scheme is referred to as synchronous demodulation for this reason. If there is a timing error between the transmitter and receiver, the receiver implements the above scheme with a shifted sinusoid in the demodulator shown in Figure.
Show that in this case the recovered message is diminished by a factor of cos(α) over the result in the ideal case.