1. The document introduces radio communication and its history, including early experiments by Maxwell, Hertz, Tesla, and Marconi in the late 19th century. 2. It describes the classification of radio waves by frequency range and the basic mechanisms, components, and uses of radio transmitters, receivers, and technology like amplitude modulation and frequency modulation. 3. Advantages of radio communication are its low cost and ability to transmit without wires, while disadvantages are low data rates and inability to transmit video or images. Future technologies discussed include cognitive radio networks.

1. Welcome To E-Shop
Presentation

2. Presented By
Hossain Md Sazzat 13-24552-2
BSc. In EEE
Faculty: A.H.M Shatil

3. Introduction
1 .Radio is the radiation of electromagnetic
signals through the atmosphere or free space.
2. The transmission and reception of
electromagnetic waves of radio frequency,
especially those carrying sound messages.

4. Brief History
Early radio testing scenario from AT & T Lab

5. History
** In 1873 James Clerk Maxwell showed mathematically
that electromagnetic waves could propagate through free
space.
** The first intentional transmission of a signal by means
of electromagnetic waves was performed in an experiment
by David Edward Hughes around 1880.
** In 1888 Heinrich Rudolf Hertz was able to prove
transmitted electromagnetic waves in an experiment
confirming Maxwell's theory of electromagnetism.

6. History
** Nikola Tesla experimentally demonstrated the
transmission and radiation of radio frequency energy in
1892 .
** 1895, Marconi built a wireless system capable of
transmitting signals at long distances (1.5 mi. / 2.4 km).
** From Marconi's experiments, the phenomenon that
transmission range is proportional to the square of antenna
height is known as "Marconi's law".

7. Classification of radio waves
Class
1 .Very Low Frequency
2.Low frequency
3. Medium frequency
4.High frequency
5.Very high frequency
6.Ultra high frequency
7.Super high frequency
Frequency Range
10 to 30 kHz
30 to 300 kHz
300 to 3000 kHz
3 to 30 MHz
30 to 300 MHz
300 to 3000 MHz
3000 to 30000 MHz

8. Mechanism

9. A transducer is a device that converts one form
of energy to another

10. Modulation
Amplitude Modulation

11. Frequency Modulation

12. Radio transmitter

13. Radio receiver

14. Different types of Transmitters
and Receivers
 Radio Frequency (RF) Chain
 Modulation Chain
 TRF Receiver
 Super heterodyne Receiver

15. TRF Receiver

16. Superheterodyne Receiver

17. Different component of a radio
receiver

18. Uses of radio waves
 Here are some common uses
1 . Wireless technology
2. Mobile telephone communication
3 .television
4 .Radar
5 .radio waves in space
6 .WiFi
And many ,many Others

25. Advantages
 It’s also a cheap form of communication and it travels
through the air so no wires are needed.
 Radio communication can be possible where any
satellite and cell phone service are not available.

26. Disadvantages
 It has low frequency so it can't transmit a lot of data
one time.
 In this communication system we can’t transfer video
or picture only voice signal can be transferred.

27. Future Technology for Radio
Communication
Cognitive Radio Networks
 Cognitive radios have the ability to monitor, sense, and
detect the conditions of their operating environment.
 A cognitive radio is an intelligent radio that can be
programmed and configured dynamically. Its
transceiver is designed to use the best wireless
channels .

28. Conclusion
 The radio communications has been used over a
hundred years now.
 The uses of radio communication increasing day by
day & its being used by a wide range of electronic
sector.
 This technology is upgrading to give us better
satisfaction

29. References
[1 ] Microphone IMAGE. Posted by Tom (2007). Houston’s
Clear Thinkers. Weblog [Online] August 22. Available
from:
http://blog.kir.com/archives/2007/08/sports_talk_rad.asp
[Accessed 22/01/11]
[ 2] National Astronauts and Space Administration. [Web
Definition] [Accessed 22/01/11] Available form:
http://science.hq.nasa.gov/kids/imagers/ems/radio.html
[3] National Astronauts and Space Administration(2010).
[Online Image] [Accessed 22/01/11] Available form:
http://science.hq.nasa.gov/kids/imagers/ems/radio.html