NPEDUCATIONS, Electronic circuits development, electronics tutorials, microcontroller tutorials and projects, advanced microcontroller (ARM) based tutorials and projects, Embedded c development, Embedded c for ARM cortex M, Intel IoT based projects, IoT projects, CC3200 launch pad projects, MSP430 Launchpad tutorials and projects, Tiva C launch pad tutorials and projects, 8051 tutorials and projects, sensor interfacing with microcontroller tutorials, data communications and networking tutorials, peripheral interfacing with microcontroller, led message scrolling display, arduino based tutorials and projects, intel galileo based tutorials and project, ADC interfacing tutorials, LED Blinking, LCD interfacing, Embedded System tutorials and projects, B.tech projects, M.tech projects, online Embedded C training

What is Modulation? Paper and Stone Analogy| Types, amplitude, frequency and phase modulation


What is Modulation? 

Modulation Definition:  Translation of Low Frequency signal to high frequency signal is generally referred as modulation. By doing so, we transfer the low frequency message signal to longer distances. This can be illustrated with paper and stone example as discussed below.

Basic need for Modulation:
Take a paper of some size and try to through it to 5-10 meter distance. It is impossible to through a plain paper to such longer distance, because the weight of that paper is very less. Now take a stone of some size and place the stone in the paper and enclose the stone. Now through the paper enclosed stone and then observe the distance travel by it. Obviously, the paper enclosed stone travels long distance than a plain paper because, the weight of the plain paper translated to higher weight of stone.


Modulation technique using paper and stone analogy
Modulation technique using paper and stone analogy

The same analogy can be applied to our communication systems, where message signal of lower frequency can be sent to longer distance by translating the message signal frequency to higher frequencies. This technique is called “frequency translation or modulation”.

If f1(t) is the message signal (paper) contains information to be transmitted and f2(t) as carrier signal (stone), then the modulated signal will be given as f1(t) X f2(t). The carrier signal is enclosed by the message signal.

Mathematically modulation is given by,

A simple proof for this modulation technique is shown by using a simple project DESIGN OF INFRARED IR TRANSMITTER AND RECEIVER CIRCUIT USING 555 TIMER AND TSOP1738.
In this project, we have been using 38khz as a carrier signal to transmit the IR signal over a long distance and at the same time it should detectable by the TSOP1738 infrared receiver. 

There three types of modulations
1. Amplitude modulation
2. Frequency modulation
3. phase modulation

0 comments :

Post a Comment

Thanks for visiting NPEDUCATIONS. We will contact you soon

0 comments :

Post a Comment

Thanks for visiting NPEDUCATIONS. We will contact you soon

If you really like this tutorial, Don't forget to give the comment or please subscribe to the RSS feed by submitting your E-mail or like our Facebook page.
Related Posts Plugin for WordPress, Blogger...

 
Powered by Blogger