Telecom, Wireless & Networks

1. Telecom, Wireless & Networks Fundamentals Media, Devices, and Software Wireless Telecommunications Networks and Distributed Computing Please discontinue use of cell phone and turn off ringer Chapter 5

2. Telecommunications Telecommunications: The electronic transmission of signals over a medium for communications. (cables or air) Sender and Receiver must “speak” the same language.

3. Voice Communication It has been said that only about 16% of spoken communication is verbal Sound waves demo demo Wave characteristics: Frequency Amplitude Phase

4. Types of Signals • Analog Signal: transmit sound using continuously varying levels of voltage. • Digital Signal: transmits data using two discrete states of voltage: high and low

5. Modulation More about waves Different waves Electromagnetic waves Analog modulation AM FM Examples

6. Digital Modulation What might FSK Look like?

7. Signal Frequency Frequency: the speed at which a signal changes from high to low. Bandwidth: the range of signal frequencies that can be sent over a given medium at the same time. Often expressed as bits per second Broadband: typically 2 – 5 Mbps

8. 5.2 Networking Media, Devices, and Software The fundamental components of telecommunications networks Key Terms • Twisted pair cable • Coaxial cable • Fiber-optic cable • Radio wave • Modem • Network adapter • Microwave transmission • Communications satellite • Ethernet

9. Networking Media • Twisted Pair Cable • Coaxial Cable • Fiber Optic Cable Used for traditional phone lines, twisted pairs of wires in plastic sheathing. Used for home cable TV, thick copper core wire – faster than twisted pair. Thin strands of glass are used to send light beams – highest bandwidth cable, most expensive. • Radio Waves Electromagnetic waves transmitted through the air at various frequencies.

10. Radio Waves Radio waves use differing frequencies to carry many types of information: AM & FM Radio Short Wave & CB Radio Television Broadcasts Garage Doors Openers Baby Monitors Cordless Phones Cell Phones Radio Controlled Cars and Airplanes Global Positioning Systems Wireless Computer Networks Microwave Communications http://electronics.howstuffworks.com/radio-spectrum1.htm

11. 300 GHz 30 GHz 2.9 GHz Deep space radio communications (2.29-2.3 GHz) Wi-fi Wireless Networks (2.4 GHz) Global Positioning System 1.23 and 1.58 GHz Air traffic Control (960-1,215 MHz) 900-MHz cordless phones Cell Phones (824-849 MHz) 328.6 MHz TV CH 7-13 (174-220 MHz) FM Radio (88-108 MHz) TV CH 2-6 (54-88 MHz) Cordless Phones (40-50 MHz) 30 MHz CB Radio (26.96-27.41 MHz) 3 MHz AM Radio (535-1700 kHz) 300kHz 30 kHz The complete picture 10 kHz The Radio Spectrum

12. Networking Devices Modem: modulates and demodulates signals from one form to another. Network Adapter: Expansion card, or external device installed on a computing device used to connect to a network.

13. Networking Devices Network Control Devices: Hub/Switch Controls flow of data between devices on a network Router Routs packets to destinations and connects one network to another Wireless Access Point Allows devices to connect wirelessly to a wired network

15. Microwave Communications High-frequency radio signals sent up to 30 miles through the air.

16. Microwave Communications ! Line-of-sight communications

17. Microwave Communications SatelliteTransmission Line-of-sight required

18. 5.3 Wireless Telecommunications Technologies Key Terms • Cellular network • Cellular carrier • Global positioning system • Wireless fidelity (wi-fi) • WiMAX • Bluetooth • Radio frequency identification • Near-field communication (NFC)

19. Cell Phone Technologies A cellular network is a radio network in which a geographic area is divided into cells, with a transmission tower and station at the center of each cell, to support mobile communications.

20. Cell Phone Technologies A cellular carrier is a company that builds and maintains a cellular network and provides cell phone service to the public.

21. GSM and CDMA Digital networking standards for cell phone networks are GSM and CDMA. GSM is the most popular global standard for mobile phones The CDMA networking standard is predominantly used in the United States where it is in equal competition with GSM.

22. GSM and CDMA GSM Phones include a subscriber identity module (SIM) for security and convenient data transfer between phones.

23. Wireless Technologies The Global Positioning System (GPS) uses satellites to pinpoint the location of receivers on earth. Aircraft Navigation How GPS works

24. Wireless Technologies Wireless Fidelity (IEEE 802.11s), or Wi-fi, is wireless networking technology that makes use of access points to connect devices to networks. AccessPoint • 250-1,000 ft range • 802.11b 4.5 Mbps • 802.11g 11 Mbps • 802.11n 74 Mbps • www.boingo.com

25. Wireless Technologies WiMAX (IEEE 802.16) is the next generation broadband technology that is both faster and has a longer range than Wi-fi – 31 miles! Seattle’s Space Needle To Become WiMax Antenna http://en.wikipedia.org/wiki/WiMAX

26. Wireless Technologies Bluetooth is wireless technology that enables a wide variety of digital devices to communicate directly. • 33 ft range • 1 Mbps • www.bluetooth.com

27. Bluetooth

28. Wireless Technologies Infrared (IrDA) technology utilizes infrared rays to send data over a short distance wirelessly. • 14 ft range • Narrow-angle cone (30o) • Line-of-sight • 4-16 Mbps • www.mzoop.com

29. Wireless Comparison