Types of Sampling Techniques
There are two types of sampling techniques :
- Flat Top PAM
- Natural PAM
Flat Top PAM
With a rectangular pulse of a defined size and duration applied across channels, the Flat Top PAM (pulse amplitude modulation) technique does the whole job perfectly. To achieve successful implementation of both transverse sampling and the required frequency range, each pulse carries the coded sample value.
The flat top pulse of the PAM builds the constancy in the signal’s amplitude over the pulse of duration that in turn makes this signal suitable for telecommunication applications.
Natural PAM
Pulse amplitude modulation, that naturally does not have shaping technique is the Natural PAM. It is not an encoding but uses the waves peaks of the nature. In demodulation, the samples individual amplitude are equal to the peak amplitude of a segment of the wave, which makes demodulation. It has the weakness of distortion and noise although its form is very simple. It appears with a multiple utilize case as simple bit transmission and/or low-cost data solutions, where the highly accurate signal retrieval is not required and the system complexity must be excluded.
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