Chapter2
- 2. The Theoretical Basis for Data Communication Fourier Analysis Bandwidth-Limited Signals Maximum Data Rate of a Channel
- 3. Bandwidth-Limited Signals A binary signal and its root-mean-square Fourier amplitudes. (b) – (c) Successive approximations to the original signal.
- 9. 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.
- 11. Fiber Cables (a) Side view of a single fiber. (b) End view of a sheath with three fibers.
- 12. Fiber Cables (2) A comparison of semiconductor diodes and LEDs as light sources.
- 15. Wireless Transmission The Electromagnetic Spectrum Radio Transmission Microwave Transmission Infrared and Millimeter Waves Lightwave Transmission
- 17. Radio Transmission (a) In the VLF, LF, and MF bands, radio waves follow the curvature of the earth. (b) In the HF band, they bounce off the ionosphere.
- 18. Politics of the Electromagnetic Spectrum The ISM bands in the United States.
- 21. Communication Satellites Communication satellites and some of their properties, including altitude above the earth, round-trip delay time and number of satellites needed for global coverage.
- 24. Low-Earth Orbit Satellites Iridium (a) The Iridium satellites from six necklaces around the earth. (b) 1628 moving cells cover the earth.
- 26. Public Switched Telephone System Structure of the Telephone System The Politics of Telephones The Local Loop: Modems, ADSL and Wireless Trunks and Multiplexing Switching
- 27. Structure of the Telephone System (a) Fully-interconnected network. (b) Centralized switch. (c) Two-level hierarchy.
- 28. Structure of the Telephone System (2) A typical circuit route for a medium-distance call.
- 29. Major Components of the Telephone System Local loops Analog twisted pairs going to houses and businesses Trunks Digital fiber optics connecting the switching offices Switching offices Where calls are moved from one trunk to another
- 30. The Politics of Telephones The relationship of LATAs, LECs, and IXCs. All the circles are LEC switching offices. Each hexagon belongs to the IXC whose number is on it.
- 31. The Local Loop: Modems, ADSL, and Wireless The use of both analog and digital transmissions for a computer to computer call. Conversion is done by the modems and codecs.
- 32. Modems (a) A binary signal (b) Amplitude modulation (c) Frequency modulation (d) Phase modulation
- 34. Modems (3) (a) V.32 for 9600 bps. (b) V32 bis for 14,400 bps. (a) (b)
- 49. The Mobile Telephone System First-Generation Mobile Phones: Analog Voice Second-Generation Mobile Phones: Digital Voice Third-Generation Mobile Phones: Digital Voice and Data
- 50. Advanced Mobile Phone System (a) Frequencies are not reused in adjacent cells. (b) To add more users, smaller cells can be used.
- 51. Channel Categories 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
- 52. D-AMPS Digital Advanced Mobile Phone System (a) A D-AMPS channel with three users. (b) A D-AMPS channel with six users.
- 53. GSM Global System for Mobile Communications GSM uses 124 frequency channels, each of which uses an eight-slot TDM system
- 54. GSM (2) A portion of the GSM framing structure.
- 55. CDMA – Code Division Multiple Access (a) Binary chip sequences for four stations (b) Bipolar chip sequences (c) Six examples of transmissions (d) Recovery of station C’s signal
- 56. Third-Generation Mobile Phones: Digital Voice and Data Basic services an IMT-2000 network should provide High-quality voice transmission Messaging (replace e-mail, fax, SMS, chat, etc.) Multimedia (music, videos, films, TV, etc.) Internet access (web surfing, w/multimedia.)