Encyclopedia > Modulator

  Article Content

Modulation

Redirected from Modulator

In music, the term "modulation" means a key change. This article is about the concept of signal modulation in communications engineering.

Modulation describes a range of techniques for encoding information on a carrier signal, typically a sine-wave signal. A device that performs modulation is known as a modulator.

Modulation techniques include:

When OFDM is used in conjunction with channel coding techniques, it is described as 'Coded orthogonal frequency division modulation' (COFDM).

Pulse modulation techniques include:

Where the signal is a simple low speed on-off indication, as in morse code or radioteletype (RTTY) transmission, modulation is often known as 'keying' as in the terms

RTTY can also be regarded as a simple kind of pulse code modulation.

Where Morse code is used to turn the carrier wave on and off, the term used is not 'amplitude keying', but 'continuous wave' (CW) operation.

Modulation is frequently used in conjunction with various channel access methods.

See also:



All Wikipedia text is available under the terms of the GNU Free Documentation License

 
  Search Encyclopedia

Search over one million articles, find something about almost anything!
 
 
  
  Featured Article
Wheatley Heights, New York

... town is $75,076, and the median income for a family is $79,745. Males have a median income of $46,444 versus $34,000 for females. The per capita income for the town is ...

 
 
 
This page was created in 36.2 ms