08-11-2012, 05:09 PM
Wireless Communications
[attachment=38637]
How Wireless Technology is Used
Wireless
Describes devices and technologies that are not connected by a wire
Wireless communications
Transmission of user data without the use of wires
Wireless data communications technologies include:
Bluetooth
Wireless LAN and WAN
Satellite
Cellular
A Wireless World
Wireless devices
Distance: 300 feet (90 meters)
Bandwidth: 54 Mbps
Can also include Voice over IP (VoIP)
Wireless network interface card (Wireless NIC)
Sends and receives data over radio waves
Smartphone
Combination mobile phone and personal digital assistant (PDA)
Bluetooth and Ultra Wide Band
Radio frequency identification device (RFID) tags
Small chips containing radio transponders
Can be used to track inventory
Bluetooth and Ultra Wide Band (UWB)
Wireless standards designed for very short ranges
Communicate using small, low-power transceivers
Link manager
Special software that helps identify other Bluetooth devices
Satellite Networks
Used to transmit data over very long distance
Repeater
Located in the satellite itself
Simply “repeats” the same signal to another location
Used to transmit data from one earth station to another
Transmission time is approximately 250 milliseconds
Cellular Networks
Modern cellular telephone network
Built around the concept of low power transmitters
With each “cell” handling a number of users
Transmission towers are spread throughout a geographical area
The same radio frequency channels can be reused by another tower
Located a few miles away to avoid interference
Maximizes the use of a limited range of frequency channels
Wireless Local Area Networks
Wireless Local Area Network (WLAN)
Extension of a wired LAN
Connecting to it through a device called a wireless access point
Access point (AP)
Relays data signals between all of the devices in the network
Each computer on the WLAN has a wireless network interface card (NIC)
With an antenna built into it
Fixed Broadband Wireless
Integrated Services Digital Networks (ISDN)
Transmit at 256 Kbps over regular phone lines
T1 lines
Transmit at 1.544 Mbps
Cable modems and digital subscriber lines (DSL)
Generally only available in residential areas
Maximum transmission speed is only about 8 Mbps
Wireless Wide Area Network
Hypertext Markup Language (HTML)
Standard language for displaying content from the Internet
Microbrowser
Miniaturized version of a Web browser
Wireless Application Protocol version 2.0 (WAP2)
Provides a standard way to transmit, format, and display Internet data
For small wireless devices such as cell phones
[attachment=38637]
How Wireless Technology is Used
Wireless
Describes devices and technologies that are not connected by a wire
Wireless communications
Transmission of user data without the use of wires
Wireless data communications technologies include:
Bluetooth
Wireless LAN and WAN
Satellite
Cellular
A Wireless World
Wireless devices
Distance: 300 feet (90 meters)
Bandwidth: 54 Mbps
Can also include Voice over IP (VoIP)
Wireless network interface card (Wireless NIC)
Sends and receives data over radio waves
Smartphone
Combination mobile phone and personal digital assistant (PDA)
Bluetooth and Ultra Wide Band
Radio frequency identification device (RFID) tags
Small chips containing radio transponders
Can be used to track inventory
Bluetooth and Ultra Wide Band (UWB)
Wireless standards designed for very short ranges
Communicate using small, low-power transceivers
Link manager
Special software that helps identify other Bluetooth devices
Satellite Networks
Used to transmit data over very long distance
Repeater
Located in the satellite itself
Simply “repeats” the same signal to another location
Used to transmit data from one earth station to another
Transmission time is approximately 250 milliseconds
Cellular Networks
Modern cellular telephone network
Built around the concept of low power transmitters
With each “cell” handling a number of users
Transmission towers are spread throughout a geographical area
The same radio frequency channels can be reused by another tower
Located a few miles away to avoid interference
Maximizes the use of a limited range of frequency channels
Wireless Local Area Networks
Wireless Local Area Network (WLAN)
Extension of a wired LAN
Connecting to it through a device called a wireless access point
Access point (AP)
Relays data signals between all of the devices in the network
Each computer on the WLAN has a wireless network interface card (NIC)
With an antenna built into it
Fixed Broadband Wireless
Integrated Services Digital Networks (ISDN)
Transmit at 256 Kbps over regular phone lines
T1 lines
Transmit at 1.544 Mbps
Cable modems and digital subscriber lines (DSL)
Generally only available in residential areas
Maximum transmission speed is only about 8 Mbps
Wireless Wide Area Network
Hypertext Markup Language (HTML)
Standard language for displaying content from the Internet
Microbrowser
Miniaturized version of a Web browser
Wireless Application Protocol version 2.0 (WAP2)
Provides a standard way to transmit, format, and display Internet data
For small wireless devices such as cell phones