Mani Raj Paul - Difference Between PAM, PWM & PPM Modulations

 Sr. No.
             Parameter PAM PWM PPM
1 Type of Carrier Train of Pulses Train of Pulses Train of Pulses
2 Variable Characteristic of the Pulsed Carrier Amplitude Width Position
3 Bandwidth Requirement Low High High
4 Noise Immunity Low High High
5 Information Contained in Amplitude Variations Width Variations Position Variations
6 Power efficiency (SNR) Low Moderate High
7 Transmitted Power Varies with amplitude of pulses Varies with variation in width Remains Constant
8 Need to transmit synchronizing pulses Not needed Not needed Necessary
9 Bandwidth depends on Bandwidth depends on the width of the pulse Bandwidth depends on the rise time of the pulse Bandwidth depends on the rise time of the pulse
10 Transmitter power Instantaneous transmitter power varies with the amplitude of the pulses Instantaneous transmitter power varies with the amplitude and width of the pulses Instantaneous transmitter power remains constant with the width of the pulses
11 Complexity of generation and detection Complex Easy Complex
12 Similarity with other Modulation Systems Similar to AM Similar to FM Similar to PM

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