Directions: It consists of two statements, one labelled as the ‘Statement (I)’ and the other as ‘Statement (II). Examine these two statements carefully and select the answer using the codes given below:

Statement (I): PAM, PWM and PPM modulation belong to analog modulation and the PCM modulation belongs to the digital modulation.

Statement (II): PAM, PWM and PPM modulations are similar to AM, FM and PM modulation.

PAM (Pulse Amplitude Modulation): In analog modulation, if the amplitude of a pulse or duration of a pulse is varied according to the instantaneous values of the baseband modulating signal, then such a technique is called as Pulse Amplitude Modulation (PAM). This is similar to AM modulation in which the carrier amplitude varies according to the modulating signal.

PWM (Pulse Width Modulation): It is a process in which output signals of low frequency are generated from the input pulse of high frequency. This is similar to the FM modulation technique.

PPM (Pulse Position Modulation): Pulse Position Modulation (PPM) is an analog modulating scheme in which the amplitude and width of the pulses are kept constant, while the position of each pulse, with reference to the position of a reference pulse, varies according to the instantaneous sampled value of the message signal. This makes it similar to a Phase modulation.

PCM (Pulse Code Modulation): It is a technique by which an analog signal gets converted into digital form to have signal transmission through a digital network. ∴ This belongs to a digital modulation scheme.