This document discusses different types of transmission media, including guided and unguided media. Guided media uses physical conduits like twisted-pair cable, coaxial cable, and fiber-optic cable to transmit signals. Unguided or wireless media transmits electromagnetic waves without a physical conductor, using radio waves, microwaves, or infrared signals. It provides details on the characteristics and applications of different guided and wireless transmission technologies.

1. 7.1
Chapter 2
Lecture 1
Transmission Media
Instructor: Tameru H. (Msc.)
Addis ababa Science and Technology University (AASTU)
Software Engineering Department

2. 7.2
Classes of transmission media

3. 7.3
GUIDED MEDIA
GUIDED MEDIA

Guided media, which are those that
Guided media, which are those that
provide a conduit from one device to
provide a conduit from one device to
another, include twisted-pair cable, coaxial
another, include twisted-pair cable, coaxial
cable, and fiber-optic cable.
cable, and fiber-optic cable.

Twisted-Pair Cable

Coaxial Cable

Fiber-Optic Cable
Guided media includes:
Guided media includes:

4. 7.4

5. 7.5
Twisted-pair cable

6. 7.6
UTP and STP cables

7. 7.7
UTP connector: RJ-45

8. 7.8
UTP performance

9. 7.9
Coaxial cable

10. 7.10
Categories of coaxial cables

11. 7.11
BNC connectors

12. 7.12
Coaxial cable performance

13. 7.13
Optical fiber

14. 7.14
Bending of light ray

15. 7.15
Propagation modes

16. 7.16
Modes

17. 7.17
Fiber types

18. 7.18
Fiber construction

19. 7.19
Fiber-optic cable connectors

20. 7.20
Optical fiber performance

21. 7.21
UNGUIDED MEDIA: WIRELESS
UNGUIDED MEDIA: WIRELESS

Unguided media transport
Unguided media transport
electromagnetic waves without using a
electromagnetic waves without using a
physical conductor. This type of
physical conductor. This type of
communication is often referred to as
communication is often referred to as
wireless
wireless communication.
communication.

Radio Waves

Microwaves

Infrared
Unguided media includes :
Unguided media includes :

22. 7.22
Electromagnetic spectrum for
wireless communication

23. 7.23
Propagation methods

24. 7.24
Bands

25. 7.25
Wireless transmission waves

26. 7.26
Radio waves

Radio waves are used for multicast
communications, such as radio and
television, and paging systems.

They can penetrate through walls.

Highly regulated.

Use omni directional antennas

27. 7.27
Omnidirectional antenna

28. 7.28
Microwaves

Microwaves are used for unicast
communication such as cellular
telephones, satellite networks,
and wireless LANs.

Higher frequency ranges cannot penetrate
walls.

Use directional antennas - point to point
line of sight communications.

29. 7.29
Unidirectional antennas

30. 7.30
Infrared

Infrared signals can be used for short-
range communication in a closed area
using line-of-sight propagation.

31. 7.31
Wireless Channels
 Are subject to a lot more errors than
guided media channels.
 Interference is one cause for errors, can be
circumvented with high SNR.
 The higher the SNR the less capacity is
available for transmission due to the
broadcast nature of the channel.
 Channel also subject to fading and no
coverage holes.