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om Zo ne C Chapter Si nh Vi en The Physical Layer SinhVienZone.com https://fb.com/sinhvienzonevn nh Vi en Zo ne Fourier Analysis Bandwidth-Limited Signals Maximum Data Rate of a Channel Si • • • C om The Theoretical Basis for Data Communication SinhVienZone.com https://fb.com/sinhvienzonevn Si nh Vi en Zo ne C om Bandwidth-Limited Signals A binary signal and its root-mean-square Fourier amplitudes (b) – (c) Successive approximations to the original signal SinhVienZone.com https://fb.com/sinhvienzonevn Si nh Vi en Zo ne C om Bandwidth-Limited Signals (2) (d) – (e) Successive approximations to the original signal SinhVienZone.com https://fb.com/sinhvienzonevn Si nh Vi en Zo ne C om Bandwidth-Limited Signals (3) Relation between data rate and harmonics SinhVienZone.com https://fb.com/sinhvienzonevn .C nh Vi en Zo ne Magnetic Media Twisted Pair Coaxial Cable Fiber Optics Si • • • • om Guided Transmission Data SinhVienZone.com https://fb.com/sinhvienzonevn Si nh Vi en Zo ne C om Twisted Pair (a) Category UTP (b) Category UTP SinhVienZone.com https://fb.com/sinhvienzonevn Si nh Vi en Zo ne C om Coaxial Cable A coaxial cable SinhVienZone.com https://fb.com/sinhvienzonevn Si nh Vi en Zo ne C om Fiber Optics (a) Three examples of a light ray from inside a silica fiber impinging on the air/silica boundary at different angles (b) Light trapped by total internal reflection SinhVienZone.com https://fb.com/sinhvienzonevn Si nh Vi en Zo ne C om Transmission of Light through Fiber Attenuation of light through fiber in the infrared region 10 SinhVienZone.com https://fb.com/sinhvienzonevn Si nh Vi en Zo ne C om Packet Switching A comparison of circuit switched and packet-switched networks 48 SinhVienZone.com https://fb.com/sinhvienzonevn om The Mobile Telephone System First-Generation Mobile Phones: Analog Voice • Second-Generation Mobile Phones: Digital Voice • Third-Generation Mobile Phones: Digital Voice and Data Si nh Vi en Zo ne C • 49 SinhVienZone.com https://fb.com/sinhvienzonevn Si nh Vi en Zo ne C om Advanced Mobile Phone System (a) Frequencies are not reused in adjacent cells (b) To add more users, smaller cells can be used SinhVienZone.com https://fb.com/sinhvienzonevn 50 Channel Categories C om The 832 channels are divided into four categories: Control (base to mobile) to manage the system • Paging (base to mobile) to alert users to calls for them • Access (bidirectional) for call setup and channel assignment • Data (bidirectional) for voice, fax, or data Si nh Vi en Zo ne • SinhVienZone.com https://fb.com/sinhvienzonevn 51 Si nh Vi en Zo ne C om D-AMPS Digital Advanced Mobile Phone System (a) A D-AMPS channel with three users A D-AMPS channel with six users (b) SinhVienZone.com https://fb.com/sinhvienzonevn 52 Si nh Vi en Zo ne C om GSM Global System for Mobile Communications GSM uses 124 frequency channels, each of which uses an eight-slot TDM system SinhVienZone.com https://fb.com/sinhvienzonevn 53 Si nh Vi en Zo ne C om GSM (2) A portion of the GSM framing structure 54 SinhVienZone.com https://fb.com/sinhvienzonevn Si nh Vi en Zo ne C om CDMA – Code Division Multiple Access (a) Binary chip sequences for four stations (b) Bipolar chip sequences (c) Six examples of transmissions Recovery of station C’s signal (d) SinhVienZone.com https://fb.com/sinhvienzonevn 55 om Third-Generation Mobile Phones: Digital Voice and Data nh Vi en Zo High-quality voice transmission Messaging (replace e-mail, fax, SMS, chat, etc.) Multimedia (music, videos, films, TV, etc.) Internet access (web surfing, w/multimedia.) Si • • • • ne C Basic services an IMT-2000 network should provide 56 SinhVienZone.com https://fb.com/sinhvienzonevn nh Vi en Zo ne C Community Antenna Television Internet over Cable Spectrum Allocation Cable Modems ADSL versus Cable Si • • • • • om Cable Television 57 SinhVienZone.com https://fb.com/sinhvienzonevn Si nh Vi en Zo ne C om Community Antenna Television An early cable television system 58 SinhVienZone.com https://fb.com/sinhvienzonevn Si nh Vi en Zo ne C om Internet over Cable Cable television 59 SinhVienZone.com https://fb.com/sinhvienzonevn Si nh Vi en Zo ne C om Internet over Cable (2) The fixed telephone system 60 SinhVienZone.com https://fb.com/sinhvienzonevn Si nh Vi en Zo ne C om Spectrum Allocation Frequency allocation in a typical cable TV system used for Internet access SinhVienZone.com https://fb.com/sinhvienzonevn 61 Si nh Vi en Zo ne C om Cable Modems Typical details of the upstream and downstream channels in North America SinhVienZone.com https://fb.com/sinhvienzonevn 62 ... radio waves follow the curvature of the earth (b) In the HF band, they bounce off the ionosphere 17 SinhVienZone.com https://fb.com/sinhvienzonevn Si nh Vi en Zo ne C om Politics of the Electromagnetic... Relaying on the ground SinhVienZone.com 25 https://fb.com/sinhvienzonevn Public Switched Telephone System nh Vi en Zo ne C om Structure of the Telephone System The Politics of Telephones The Local... from one trunk to another 29 SinhVienZone.com https://fb.com/sinhvienzonevn Si nh Vi en Zo ne C om The Politics of Telephones The relationship of LATAs, LECs, and IXCs All the circles are LEC