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A Modulation PPT (PowerPoint Presentation) typically covers the concept of modulation in communication systems. Modulation is the process of varying a carrier signal to transmit information efficiently over long distances. Here's a structured outline for your Modulation PPT:

Title Slide
Title: Modulation in Communication Systems
Subtitle: Types, Techniques, and Applications
1. Introduction to Modulation
Definition of modulation
Importance of modulation in communication
Examples of modulation in daily life (Radio, TV, Mobile Networks)
2. Need for Modulation
Overcoming signal transmission limitations
Efficient use of bandwidth
Reducing noise and interference
Multiplexing different signals
3. Types of Modulation
A. Analog Modulation
Amplitude Modulation (AM) – Explanation, waveform, advantages & disadvantages
Frequency Modulation (FM) – Explanation, waveform, advantages & disadvantages
Phase Modulation (PM) – Explanation, waveform, advantages & disadvantages
B. Digital Modulation
Amplitude Shift Keying (ASK)
Frequency Shift Keying (FSK)
Phase Shift Keying (PSK)
Quadrature Amplitude Modulation (QAM)
4. Modulation Techniques
Carrier signal characteristics
Waveforms of different modulation techniques
Comparison of modulation types
5. Applications of Modulation
Broadcasting (Radio & TV)
Mobile communication (2G, 3G, 4G, 5G)
Satellite communication
Internet data transmission
6. Advantages & Disadvantages of Modulation
Improved signal transmission
Reduced interference
Efficient bandwidth utilization
Complexity in receiver design
7. Conclusion
Summary of key points
Future trends in modulation (5G, Optical Communication, IoT)
Q&A session

1. 1
Amplitude ModulationAmplitude Modulation

2. 2
ContentContent
•What is Modulation
•Amplitude Modulation (AM)
•Mathematical expresion
•Frequency modulation (FM) and Phase
modulation (PM)
•Mathematical expression
•Super – heterodyne receiver
•Digital modulation

3. 3
What is ModulationWhat is Modulation
•Modulation
–In the modulation process, some characteristic
of a high-frequency carrier signal (bandpass), is
changed according to the instantaneous
amplitude of the information (baseband) signal.
•Why Modulation
–Suitable for signal transmission (distance…etc)
–Multiple signals transmitted on the same channel
–Capacitive or inductive devices require high
frequency AC input (carrier) to operate.
–Stability and noise rejection

4. 4
About ModulationAbout Modulation
•Application Examples
–broadcasting of both audio
and video signals.
–Mobile radio communications,
such as cell phone.
•Basic Modulation Types
–Amplitude Modulation: changes the amplitude.
–Frequency Modulation: changes the frequency.
–Phase Modulation: changes the phase.

5. Example Amplitude modulation

6. 6
Amplitude ModulationAmplitude Modulation
•The amplitude of high-carrier signal is
varied according to the instantaneous
amplitude of the modulating message
signal m(t).
Carrier Signal: or
Modulating Message Signal: or
The AM Signal:
cos(2 ) cos( )
(): cos(2 ) cos( )
() [ ()]cos(2 )
c c
m m
AM c c
ft t
mt f t t
s t A mt ft
 
 
 

7. 7
Amplitude ModulationAmplitude Modulation
•The AM signal is generated using a
multiplier.
•All info is carried in the amplitude of
the carrier, AM carrier signal has
time-varying envelope.
•In frequency domain the AM
waveform are the lower-side
frequency/band (f
c - f
m), the carrier
frequency f
c
, the upper-side
frequency/band (f
c + f
m).

8. 8
Spectrum powerSpectrum power
•It is important to use as high percentage of
modulation as possible (k=1) while ensuring
that over modulation (k>1) does not occur.
•The sidebands contain the information and have
maximum power at 100% modulation.
•Useful equation
P
t = P
c(1 + m
2
/2)
P
t
=Total transmitted power (sidebands and
carrier)
P
c = Carrier power