Assume that an AM system operates with an index
of 0.6 and that the message signal is 12 cos (8π) . Compute the efficiency, the detection gain in dB, and the output SNR in decibels relative to the baseband performance PT /N0W. Determine the improvement (in decibels) in the output SNR that results if the modulation index is increased from 0.6 to 0.9.