modulation and demodulation

Demodulation - Demodulation is the process of recovering the signal intelligence from a modulated carrier wave. This process, also called detection, is the reverse process of modulation..

Demodulation is the process of recovering the signal intelligence from a modulated carrier wave. This process, also called detection, is the reverse process of modulation..

The wireless signal consists of radio frequency (high frequency) carrier wave modulated by audio frequency (low frequency). The diaphragm of a telephone receiver or a loud speaker cannot vibrate with high frequency. Moreover, this frequency is beyond the audible range of human ear. So, i..

c . In amplitude modulation, the amplitude of the wave is varied duplicating faithfully the fluctuations of the message. At the receiver these variations are detected or demodulated i.e., the message is removed from the carrier. (Although the more precise terms are demodul..

It is also referred to as pulse-width modulation. It varies the pulse length or duration around a fixed value. This may be done by shifting either the leading or trailing edge, or both, as a function of the sampled amplitude. Greater channel band width is required than for PAM. Design mu..

The 'modem' is a contraction of the term modulator-demodulator. It is a conversion that facilitates the transmission and reception of the data over the public switched telephone network (PSTN..

For demodulation, the modulated wave is fed to a circuit. This circuit is called detector. The output of the detector must have the same variations as the signal that modulated the carrier. If the variation in the output of the detector is not the same, then we say th..

What is a Modem? - A modem (a modulator/demodulator) lets you connect your computer to a standard telephone line so that you can transmit and receive electronically transmitted data. It is the key that unlocks the world of the Internet and its World Wide Web, commercial online services, e..

Basic Principles of Wireless Radio Communication - Let us now discuss the basic principles of wireless radio communications. We shall mainly concentrate on the principle of amplitude modulation and demodulation. The simplest scheme of wireless communication would be to convert t..

How Modems Work? - When a modem first makes a connection, you will hear screeching sounds coming from the modem. These are digital signals coming from the computer to which you are connecting being modulated into audible sounds. The modem sends a higher-pitched tone to represent the digit..