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Lecture Data communications and networks: Chapter 7 - Forouzan 

A computer network is designed to send information from one point to another. This information needs to be converted to either a digital signal or an analog signal for transmission. In this chapter, we discuss the first choice, conversion to digital signals. | Chapter 7 Transmission Media Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 7. Figure 7.1 Transmission medium and physical layer 7. Figure 7.2 Classes of transmission media 7. 7-1 GUIDED MEDIA Guided media, which are those that provide a conduit from one device to another, include twisted-pair cable, coaxial cable, and fiber-optic cable. Twisted-Pair Cable Coaxial Cable Fiber-Optic Cable Topics discussed in this section: 7. Figure 7.3 Twisted-pair cable 7. Figure 7.4 UTP and STP cables 7. Table 7.1 Categories of unshielded twisted-pair cables 7. Figure 7.5 UTP connector 7. Figure 7.6 UTP performance 7. Figure 7.7 Coaxial cable 7. Table 7.2 Categories of coaxial cables 7. Figure 7.8 BNC connectors 7. Figure 7.9 Coaxial cable performance 7. Figure 7.10 Bending of light ray 7. Figure 7.11 Optical fiber 7. Figure 7.12 Propagation modes 7. Figure 7.13 Modes 7. Table 7.3 Fiber types 7. Figure 7.14 Fiber construction 7. Figure 7.15 Fiber-optic cable connectors 7. Figure 7.16 Optical fiber performance 7. 7-2 UNGUIDED MEDIA: WIRELESS Unguided media transport electromagnetic waves without using a physical conductor. This type of communication is often referred to as wireless communication. Radio Waves Microwaves Infrared Topics discussed in this section: 7. Figure 7.17 Electromagnetic spectrum for wireless communication 7. Figure 7.18 Propagation methods 7. Table 7.4 Bands 7. Figure 7.19 Wireless transmission waves 7. Figure 7.20 Omnidirectional antenna 7. Radio waves are used for multicast communications, such as radio and television, and paging systems. Note 7. Figure 7.21 Unidirectional antennas 7. Microwaves are used for unicast communication such as cellular telephones, satellite networks, and wireless LANs. Note 7. Infrared signals can be used for short-range communication in a closed area using . | Chapter 7 Transmission Media Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 7. Figure 7.1 Transmission medium and physical layer 7. Figure 7.2 Classes of transmission media 7. 7-1 GUIDED MEDIA Guided media, which are those that provide a conduit from one device to another, include twisted-pair cable, coaxial cable, and fiber-optic cable. Twisted-Pair Cable Coaxial Cable Fiber-Optic Cable Topics discussed in this section: 7. Figure 7.3 Twisted-pair cable 7. Figure 7.4 UTP and STP cables 7. Table 7.1 Categories of unshielded twisted-pair cables 7. Figure 7.5 UTP connector 7. Figure 7.6 UTP performance 7. Figure 7.7 Coaxial cable 7. Table 7.2 Categories of coaxial cables 7. Figure 7.8 BNC connectors 7. Figure 7.9 Coaxial cable performance 7. Figure 7.10 Bending of light ray 7. Figure 7.11 Optical fiber 7. Figure 7.12 Propagation modes 7. Figure 7.13 Modes 7. Table 7.3 Fiber .