Types of Pulse Amplitude Modulation
Given below are the Types of Pulse Amplitude Modulation
- Single-Pulse Amplitude Modulation (SPAM) –One pulse is used to represent each symbol in SPAM. This pulse’s amplitude varies based on the incoming signal. Generally, each pulse’s duration matches the period of a symbol.
- Double-Pulse Amplitude Modulation (DPAM)- DPAM is an advanced variant of PAM in which two pulses are used to represent each symbol. There is a specific amount of time between these pulses. Each pulse in the pair has its amplitude altered to reflect various amplitude levels. When it involves strength against channel limitations and noise performance, DPAM is preferable over SPAM.
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