If S represents the carrier synchronization at the receiver and r represents the bandwidth efficiency, then the correct statement for the coherent binary PSK is

ANS:D - r = 1.0, S is not required

The correct statement for the coherent binary PSK is that the bandwidth efficiency is 0.5, and carrier synchronization is required. Explanation The bandwidth efficiency of coherent binary PSK is 0.5, meaning that only two bits can be transmitted per symbol. This is because the phase of the carrier wave is used to transmit digital symbols, and only two phases are available.

Carrier synchronization is required for coherent binary PSK because the receiver needs to know the carrier wave's phase to correctly demodulate the received signal. Without carrier synchronization, the receiver will not be able to distinguish between the two phases and decode the received signal correctly.