Slide 1Slide 2Slide 3Slide 4Slide 5Slide 6Slide 7Slide 8Slide 9Slide 10Slide 11Slide 12Slide 13Slide 14Slide 15Slide 16Slide 17Slide 18Slide 19Slide 20Slide 21Slide 22Slide 23Slide 24Slide 25Electromagnetic spectrum for wireless communicationSlide 27Slide 28Slide 29Slide 30Example: Omnidirectional antennaSlide 32Slide 33Slide 34Slide 35Example: Unidirectional AnntenaExample: Homemade Unidirectional Antenna - Can antennaExample: Homemade Unidirectional AntennaAdvantages and Disadvantages Wireless Communication7.1Chapter 7Transmission MediaCopyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.7.2Figure 7.1 Transmission medium and physical layer7.3Figure 7.2 Classes of transmission media7.47-1 GUIDED MEDIA7-1 GUIDED MEDIAGuided media, which are those that provide a conduit Guided 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 CableCoaxial CableFiber-Optic CableTopics discussed in this section:Topics discussed in this section:7.5Figure 7.3 Twisted-pair cable7.6Figure 7.4 UTP and STP cables7.7Table 7.1 Categories of unshielded twisted-pair cables7.8UTP cables1 – Jacket2 – Solid twisted pair3 – Spacer7.9SSTP cables1 – Jacket2 – Shield-braid3 – Shield-foil4 – Stranded twisted pair7.10Figure 7.5 UTP connector7.11Figure 7.6 UTP performance7.12Figure 7.7 Coaxial cable7.13Table 7.2 Categories of coaxial cables7.14Figure 7.8 BNC connectors7.15Figure 7.9 Coaxial cable performance7.16Figure 7.10 Bending of light ray7.17Figure 7.11 Optical fiber7.18Figure 7.12 Propagation modes7.19Figure 7.13 Modes7.20Table 7.3 Fiber types7.21Figure 7.14 Fiber construction7.22Figure 7.15 Fiber-optic cable connectors7.23Figure 7.16 Optical fiber performance7.247-2 UNGUIDED MEDIA: WIRELESS7-2 UNGUIDED MEDIA: WIRELESSUnguided media transport electromagnetic waves Unguided media transport electromagnetic waves without using a physical conductor. This type of without using a physical conductor. This type of communication is often referred to as wireless communication is often referred to as wireless communication.communication.Radio WavesMicrowavesInfraredTopics discussed in this section:Topics discussed in this section:7.25Figure 7.17 Electromagnetic spectrum for wireless communication7.26Electromagnetic spectrum for wireless communication7.27Figure 7.18 Propagation methods7.28Table 7.4 Bands7.29Figure 7.19 Wireless transmission waves7.30Figure 7.20 Omnidirectional antenna7.31Example: Omnidirectional antenna Use:Wireless router7.32Radio waves are used for multicast communications, such as radio and television, and paging systems.Note7.33Figure 7.21 Unidirectional antennas7.34Microwaves are used for unicast communication such as cellular telephones, satellite networks,and wireless LANs.Note7.35Infrared signals can be used for short-range communication in a closed area using line-of-sight propagation.Note7.36Example: Unidirectional AnntenaUse:Wireless link connecting two remote WLANs7.37Example: Homemade Unidirectional Antenna - Can antenna7.38Example: Homemade Unidirectional AntennaUse:Cellular Anntena TowerAdvantages and Disadvantages Wireless CommunicationAdvantagesUser MobilityEasy to installReduced costScalabilityDisadvantagesHigh data error rateLower transmission data ratesSecurityBattery of Mobile DevicesHealth