Modulation is the addition of information to an
electronic or optical carrier signal. It is a process of mixing a signal with a
sinusoid to produce a new signal.
In electronics and telecommunications, modulation is the
process of varying one or more properties of a periodic waveform, called the
carrier signal, with a modulating signal that typically contains information to
be transmitted
There are 3 basic types of modulation:
Amplitude
Modulation
A type of modulation where the amplitude of the carrier
signal is modulated (changed) in proportion to the message signal while the
frequency and phase are kept constant.
Frequency
Modulation
A type of modulation where the frequency of the carrier
signal is modulated (changed) in proportion to the message signal while the
amplitude and phase are kept constant.
Phase
Modulation
A type of modulation where the phase of the carrier
signal is varied accordance to the low frequency of the message signal is known
as phase modulation.
