Pulse Amplitude Modulation
What factors affect pulse amplitude modulation?
The amplitude of the pulse carrier varies in the pulse amplitude modulation, or PAM, approach and is proportional to the instantaneous amplitude of the message signal.
What is Aperture effect in pulse amplitude Modulation?
When the sample window width during demodulation might result in distortion or mistakes in the recovered signal, this is known as the aperture effect in pulse amplitude modulation, or PAM. When the sampling rate is low or the modulation frequency is high, this impact is more apparent. Precise time-based synchronization, suitable demodulation methods, and sampling window width optimization are essential to mitigate this.
How is PAM different from PWM and PPM?
Pulse Width Modulation (PWM) varies the width of pulses, Pulse Position Modulation (PPM) varies the position of pulses, while PAM varies the amplitude of pulses.
Pulse Amplitude Modulation
Pulse Amplitude Modulation (PAM) is a key modulation technique used in digital communication for transmitting analog data and is one of the most widely used types of analog-to-digital conversion. Its process is simple where the amplitude of a sequence of pulses changes with the instantaneous amplitude of the analog message signal. The analog signal that is to be modulated is sampled by a sequence of pulses that are amplitude-modulated on the carrier to produce the amplitude-modulated pulses.
The analog signal is sampled at regular intervals to enable the amplitude of pulses due to be produced by the carrier to be varied. The sampled values are quantized to a specific number of quantization levels or discrete levels whereupon the process is repeated. Due to its simplicity of implementation and analysis, PAM is often employed in many applications including digital communication, audio transmission, and instrumentation among others. One of the biggest drawbacks of PCM is its sensitivity towards channel errors, as poor-quality channels will introduce noise and distortion, particularly over larger distances and lower data rates.
Table of Content
- What is PAM?
- PAM Block Diagram
- Types
- Mathematical expression
- Construction
- PAM Circuit
- Solved Examples on PAM
- Applications
- Advantages
- Disadvantages