This document discusses different types of analog modulation techniques used in communication systems. It defines key concepts like signals, carriers, modulation and demodulation. There are three main types of analog modulation covered - amplitude modulation, frequency modulation, and phase modulation. Each works by varying a different property of the carrier signal (amplitude, frequency, or phase respectively) according to the information-bearing signal.

2. Introduction
I. Signals
II. Carrier
Modulation and Demodulation
Types of analog modulation
technique
I. Amplitude modulation
II. Frequency modulation
III. Phase modulation

3. Signals :-
Signal is defined as the useful information which is
sanded by the transmitter and received by the
receiver.
Carrier:-
Carrier is defined as a very high frequency signal over
which information is mounted and sanded through the
channel or medium.

4. Modulation:-
Modulation is defined as the process
or phenomenon by which the signal
is mounted over the carrier signal
and the signal so obtained is called
as modulated signal.
Demodulation:-
Demodulation is defined as
extracting the original signal from the
received modulated signal.
Modulation
Demodulation

5. Analog
modulation
Amplitude
modulation
Frequency
modulation
Phase
modulation

6. Amplitude modulation (A.M.):-
In Amplitude modulation the carrier amplitude is changed according
to the signal.
Frequency modulation (F.M.):-
In Frequency modulation the carrier frequency is changed according
to the signal.
Amplitude
Time

7. Phase modulation (P.M.):-
In Phase modulation the carrier phase is changed according to the
signal.
In positive amplitude the carrier phase is same and in negative
amplitude the carrier phase is reversed to is original phase .
Amplitude
Time