From Bluetooth to WIFI
Connection technologies
Radio frequency Bands;
The RF Spectum extends from 3kHz to 300GHz. The most important are those (for this subject)
these bands are unlicend:
The 2.4 - 2.5 GHz for IEEE 802.11b, Bluetooth and Home Cordless phones and microwave ovens
And the 5Ghz for IEEE 802.11.
Bluetooth
A wireless interconnect technology standard, designed to replace the many cables we need to connect devices. This technology will let you walk into a room and communicate with your PC or other Bluetooth-compliant devices. The Bluetooth specification was created in February 1998 by a consortium comprising inventive minds from Ericsson, IBM, Intel, Nokia and Toshiba
The odd name is derived from an aggressive Viking king so fond of blueberries that they stained his teeth.
Bluetooth is a good, low-power data/voice transmission standard that will be a real boon for certain applications. Imagine a cell phone or pager that automatically transfers to vibrate mode when you enter a restaurant or theater. Or a laptop and GPS (global positioning system) that automatically feed a display in your car for directions. One of Bluetooth's design strengths is its low cost. The Bluetooth SIG says integrating this technology should add only $5 to the cost of a unit.
Bluetooth operates in the 2.4 Ghz band and got 3 power classes:
Class 1: 100 milliwatt, 20 dBm, 1Mbs, 100 Meters
Class 2: 2.5 milliwatt, 4 dBm, 1Mbs, 10 Meters
Class 3: 1 milliwatt, 0 dBm, 1Mbs, 10 Meters
The speed of 1Mbs and the distances are under optimal conditions, normaly a speed of 700-800 Kbs is more likely
Bluetooth traffic has 2 types; Voice and data. Voice traffic has a much lower tolerance for interference than does data traffic.
The security of the bluetooth network is less than wonderful. You have 3 types;
Level 1: No security.
Level 2: Service-level-enforced security. Security is established after channel negotiation.
Level 3: Link-level-enforced security
The second level is the most used.
and for those who wanna know;
there are 5 stages of activity of a bluetooth network: standby, inquire, page, connect and park/hold.
Standby is a radio waiting to join a piconet (PAN).
Inquire is a radio seeking other radios to connect.
Page is a master radio asking to connect to a specific radio.
Connect is a radio active on a piconet as a master, slave or simultaneous.
Park/hold is a low-power connected state.
IEEE 802.11a, b, g,... or WIFI
Wifi is much more faster than Bluetooth with speeds up to 11-54 Mbs and a operation range of 400 meters.
There are some basic differences between. Bluetooth is designed for connecting 2 or more devices for sharing data and voice and Wifi is more designed to connect a whole network.
the standards from a to g are updates on speed and security;
802.11a
An IEEE specification for wireless networking that operates in the 5 GHz frequency range (5.725 GHz to 5.850 GHz) with a maximum 54 Mbps data transfer rate. The 5 GHz frequency band is not as crowded as the 2.4 GHz frequency, because the 802.11a specification offers more radio channels than the 802.11b. These additional channels can help avoid radio and microwave interference.
802.11b
International standard for wireless networking that operates in the 2.4 GHz frequency range (2.4 GHz to 2.4835 GHz) and provides a throughput of up to 11 Mbps. This is a very commonly used frequency. Microwave ovens, cordless phones, medical and scientific equipment, as well as Bluetooth devices, all work within the 2.4 GHz frequency band.
802.11g
Similar to 802.11b, but this standard provides a throughput of up to 54 Mbps. It also operates in the 2.4 GHz frequency band but uses a different radio technology in order to boost overall bandwidth.
WIMAX or Super WIFI
Wimax is a technologie that allows to provide internetconnection of a hole city. It has a speed of 70Mbs and it can carry signals over distances of 50Km. This a direct threat to the 3G network althow it can't carry voice, it can be used for VOIP (voice over IP). This technologie is just in developing fase and will be available at the beginning of 2005.
IR of Infrared
Infrared uses the invisable red light to communicate with devices. it need a staight line up between transmitter and reciever within 1 meter. The speed can go up to 4Mbs (high speed infrared connection) but normaly with mobile phones the speed is not more then 115Kbs.
Radio frequency Bands;
The RF Spectum extends from 3kHz to 300GHz. The most important are those (for this subject)
these bands are unlicend:
The 2.4 - 2.5 GHz for IEEE 802.11b, Bluetooth and Home Cordless phones and microwave ovens
And the 5Ghz for IEEE 802.11.
Bluetooth
A wireless interconnect technology standard, designed to replace the many cables we need to connect devices. This technology will let you walk into a room and communicate with your PC or other Bluetooth-compliant devices. The Bluetooth specification was created in February 1998 by a consortium comprising inventive minds from Ericsson, IBM, Intel, Nokia and Toshiba
The odd name is derived from an aggressive Viking king so fond of blueberries that they stained his teeth.
Bluetooth is a good, low-power data/voice transmission standard that will be a real boon for certain applications. Imagine a cell phone or pager that automatically transfers to vibrate mode when you enter a restaurant or theater. Or a laptop and GPS (global positioning system) that automatically feed a display in your car for directions. One of Bluetooth's design strengths is its low cost. The Bluetooth SIG says integrating this technology should add only $5 to the cost of a unit.
Bluetooth operates in the 2.4 Ghz band and got 3 power classes:
Class 1: 100 milliwatt, 20 dBm, 1Mbs, 100 Meters
Class 2: 2.5 milliwatt, 4 dBm, 1Mbs, 10 Meters
Class 3: 1 milliwatt, 0 dBm, 1Mbs, 10 Meters
The speed of 1Mbs and the distances are under optimal conditions, normaly a speed of 700-800 Kbs is more likely
Bluetooth traffic has 2 types; Voice and data. Voice traffic has a much lower tolerance for interference than does data traffic.
The security of the bluetooth network is less than wonderful. You have 3 types;
Level 1: No security.
Level 2: Service-level-enforced security. Security is established after channel negotiation.
Level 3: Link-level-enforced security
The second level is the most used.
and for those who wanna know;
there are 5 stages of activity of a bluetooth network: standby, inquire, page, connect and park/hold.
Standby is a radio waiting to join a piconet (PAN).
Inquire is a radio seeking other radios to connect.
Page is a master radio asking to connect to a specific radio.
Connect is a radio active on a piconet as a master, slave or simultaneous.
Park/hold is a low-power connected state.
IEEE 802.11a, b, g,... or WIFI
Wifi is much more faster than Bluetooth with speeds up to 11-54 Mbs and a operation range of 400 meters.
There are some basic differences between. Bluetooth is designed for connecting 2 or more devices for sharing data and voice and Wifi is more designed to connect a whole network.
the standards from a to g are updates on speed and security;
802.11a
An IEEE specification for wireless networking that operates in the 5 GHz frequency range (5.725 GHz to 5.850 GHz) with a maximum 54 Mbps data transfer rate. The 5 GHz frequency band is not as crowded as the 2.4 GHz frequency, because the 802.11a specification offers more radio channels than the 802.11b. These additional channels can help avoid radio and microwave interference.
802.11b
International standard for wireless networking that operates in the 2.4 GHz frequency range (2.4 GHz to 2.4835 GHz) and provides a throughput of up to 11 Mbps. This is a very commonly used frequency. Microwave ovens, cordless phones, medical and scientific equipment, as well as Bluetooth devices, all work within the 2.4 GHz frequency band.
802.11g
Similar to 802.11b, but this standard provides a throughput of up to 54 Mbps. It also operates in the 2.4 GHz frequency band but uses a different radio technology in order to boost overall bandwidth.
WIMAX or Super WIFI
Wimax is a technologie that allows to provide internetconnection of a hole city. It has a speed of 70Mbs and it can carry signals over distances of 50Km. This a direct threat to the 3G network althow it can't carry voice, it can be used for VOIP (voice over IP). This technologie is just in developing fase and will be available at the beginning of 2005.
IR of Infrared
Infrared uses the invisable red light to communicate with devices. it need a staight line up between transmitter and reciever within 1 meter. The speed can go up to 4Mbs (high speed infrared connection) but normaly with mobile phones the speed is not more then 115Kbs.
mobilelife - 2004-12-30 16:42
Trackback URL:
http://mobilelife.twoday.net/stories/456417/modTrackback