news details |
|
|
| "How Blue Tooth Works" | | | D.K Mota | 11/20/2011 9:54:08 PM |
| Blue tooth is an open standard and specification for
small form factor, low cost and short range radio
links links between Mobile PCS, low cost and short range radio links between Mobile Phones and other portable devices. This Technology allows user to form wireless connections between various communication devices to transmit voice and data.
In 1998, five companies as Blue tooth Promoters:-
Ericsson, IBM, INTEL, NOKIA and Toshiba organized jointly. Three companies "LUCENT" "MICROSOFT" and "Motorola was joined by othe4r member adopter companies and the first version came in 1999.
Blue tooth radio is built into a small microchip and operates in 2.4 Gzs Band. It use frequency hopping spectrum which changes its signal 1600 times per second which helps t avoid interception by un authorized Parties. The software controls and identity conding" built into each microchip ensure that only those units preset by their owners can communicate. It can support point to multipoint connections and data transfer within Ten mts distance with a power boost. The technology uses " Omni directional" radio waves, upto 7 slaves devices can be set to communicate with master Radio in one devices can be set to communicate with master Radio in one device.
Blue tooth Protocols are designated to operate in 2.4 Gzs ISM band. Each Chl is 1MHZS wide and so there are 79 diff. Chls. Spread spectrum Technologies help to avoid interference between Radio Technologies. A Blue tooth device changes its frequency 1600 times/ Sec Interfrence often occurs in a small Portion of frequency band so hopping between different frequencies makes Chl. In sensitive corrupt packets are resent on another frequency on which same interference may not exist. Master device decides on a hopping scheme that is related to its internal clock. And the slave calculates an offset difference between master and slave clocks and uses this information to determine the frequency to which it will hope.
This is possible by embedding a tiny in expensive chip in a short range Transceiver ito a mobile. The device which initiates the connection is called "MASTER" device and the connected devices are called slaves.
If a person is trying to connect his services (Known device) Then the master device will send a page command which checks whether the device is within the range. If so connection is established.
Despite of Master/ Slave designation, the network behaves more of peer to peer relation. Each device has equal access to the entire network. A slave device in a net work can establish connections ot other networks also me advantages are as under.
Blue tooth Technology supports all multimedia applications.
The flexible Network that allows upto 8 devices to share the information.
Power consumption is low.
And lastly it has a support of security considerations like "Encryption"
Author is Sub Div Engineer BSNL Leased Lines N/Works Gandhi Nagar Jammu
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
| |
|
|
|
|
 |
|
|
|
|
STOCK UPDATE |
|
|
 |
| BSE
Sensex |
 |
| NSE
Nifty |
|
|
| |
CRICKET UPDATE |
|
|
|
|
| |
| |
|
|
| |
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
