This document section discusses different types of transmission media, including guided media like twisted-pair cable, coaxial cable, and fiber-optic cable. It also discusses unguided or wireless media that transmit electromagnetic waves without a physical conductor, including radio waves, microwaves, and infrared signals. Guided media provide a conduit to transmit signals from one device to another, while wireless media transport signals through the air using electromagnetic waves and antennas.

1. 7.1
Chapter 7
Transmission Media
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2. 7.2
Figure 7.1 Transmission medium and physical layer

3. 7.3
Figure 7.2 Classes of transmission media

4. 7.4
7-1 GUIDED MEDIA7-1 GUIDED MEDIA
Guided media, which are those that provide a conduitGuided media, which are those that provide a conduit
from one device to another, include twisted-pair cable,from one device to another, include twisted-pair cable,
coaxial cable, and fiber-optic cable.coaxial cable, and fiber-optic cable.
Twisted-Pair Cable
Coaxial Cable
Fiber-Optic Cable
Topics discussed in this section:Topics discussed in this section:

5. 7.5
Figure 7.3 Twisted-pair cable

6. 7.6
Figure 7.4 UTP and STP cables

7. 7.7
Table 7.1 Categories of unshielded twisted-pair cables

8. 7.8
Figure 7.5 UTP connector

9. 7.9
Figure 7.6 UTP performance

10. 7.10
Figure 7.7 Coaxial cable

11. 7.11
Table 7.2 Categories of coaxial cables

12. 7.12
Figure 7.8 BNC connectors

13. 7.13
Figure 7.9 Coaxial cable performance

14. 7.14
Figure 7.10 Bending of light ray

15. 7.15
Figure 7.11 Optical fiber

16. 7.16
Figure 7.12 Propagation modes

17. 7.18
Table 7.3 Fiber types

18. 7.19
Figure 7.14 Fiber construction

19. 7.20
Figure 7.15 Fiber-optic cable connectors

20. 7.21
Figure 7.16 Optical fiber performance

21. 7.22
7-2 UNGUIDED MEDIA: WIRELESS7-2 UNGUIDED MEDIA: WIRELESS
Unguided media transport electromagnetic wavesUnguided media transport electromagnetic waves
without using a physical conductor. This type ofwithout using a physical conductor. This type of
communication is often referred to as wirelesscommunication is often referred to as wireless
communication.communication.
Radio Waves
Microwaves
Infrared
Topics discussed in this section:Topics discussed in this section:

22. 7.23
Figure 7.17 Electromagnetic spectrum for wireless communication

23. 7.25
Table 7.4 Bands

24. 7.26
Figure 7.19 Wireless transmission waves

25. 7.27
Figure 7.20 Omnidirectional antenna

26. 7.28
Radio waves are used for multicast
communications, such as radio and
television, and paging systems.
Note

27. 7.29
Figure 7.21 Unidirectional antennas

28. 7.30
Microwaves are used for unicast
communication such as cellular
telephones, satellite networks,
and wireless LANs.
Note

29. 7.31
Infrared signals can be used for short-
range communication in a closed area
using line-of-sight propagation.
Note