abstract
| - These terms are traditionally used in connection with radio receivers, but many other systems use many kinds of demodulator. Another common one is in a modem, which is a contraction of the terms modulator/demodulator.
- Demodulation is the act of extracting the original information-bearing signal from a modulated carrier wave.
- Demodulation is the act of removing the modulation from an analog signal to get the original baseband signal back. Demodulating is necessary because the receiver system receives a modulated signal with specific characteristics and it needs to turn it to base-band. There are several ways of demodulation depending on what parameters of the base-band signal are transmitted in the carrier signal, such as amplitude, frequency or phase. For example, if we have a signal modulated with a lineal modulation, like AM (Amplitude Modulated), we can use a synchronous detector. On the other hand, if we have a signal modulated with an angular modulation, we must use an FM (Frequency Modulated) demodulator or a PM (Phase Modulated) demodulator. There are different kinds of circuits that make these functions. An example of a demodulation system is a modem, which receives a telephone signal (electrical signal) and turns this signal from the wire net into a binary signal for the computer. A demodulator is an electronic circuit used to recover the information content from the carrier wave of a signal. The term is usually used in connection with radio receivers, but there are many kinds of demodulators used in many other systems. Another common one is in a modem, which is a contraction of the terms modulator/demodulator.
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