1. BLUETOOTH WIRELESS TECHNOLOGY
Maureen Stella B. Lim

2. What is Bluetooth?
A way to form connections between electronic devices in close proximity
Cable-replacement technology
It is a radio-frequency technology that uses the 2.4 GHz Industrial-Scientific-Medical (ISM) band
To be Bluetooth certified, a device must pass interoperability testing by the Bluetooth Special Interest Group (SIG), thus assuring that products meeting the specification will be able to interact with all other Bluetooth-certified products.

3. Bluetooth
ideal for small devices, short range, and low power radio links
fit for connecting PCs and laptop computers, phones, printers, and cameras.
Low power Bluetooth devices have a range of about 30 feet.

4. Bluetooth Features Wireless and automatic Inexpensive
The ISM band that Bluetooth uses is regulated, but unlicensed.
Handles both voice and data
Signals are omni-directional
Uses frequency hopping

5. Network Topology M S M S S
Piconet
Scatternet

6. Packets All data on the piconet channel are conveyed in packets
Each packet consists of three entities
Acces Code = used for timing synchronization, offset compensation, paging and inquiry
Header = information for packet acknowledgment, numbering, flow control, slave address, error check
Payload = voice field or data field

7. Radio Frequency and Spectrum Hopping
Uses fast acknowledgment and frequency-hopping
Bluetooth divides the 2.4 GHz frequency band into 79 channels (from to GHz)
Jumps to a new frequency after every packet

8. Physical Channel
Piconets are formed by two or more Bluetooth devices using the same channel
The channel is represented by a pseudo-random hopping sequence
Hopping sequence - unique for each piconet and determined by the Bluetooth device address of the master
Phase - determined by the Bluetooth clock of the master M S
Piconet
Master
Slave

9. Physical Channel
The channel is divided into time slots, each 625 microseconds long
Time-division multiplexing (TDM) scheme = a master device always uses an even-numbered slot when it transmits, and a slave uses an odd-numbered slot.

10. Physical Links 1. Synchronous Connection Oriented (SCO)
Symmetric point-to-point link
Carries voice information
Reserved time slots to guarantee timely transmission
Works at 64 Kb/s

11. Physical Links 2. Asynchronous Connection Less (ACL)
Primarily for data
Established on a per-slot basis
Support point-to-multipoint transmissions
A slave can only transmit only after receiving a packet from a master
For this purpose, the master can send a polling packet
Can transmit as much as 721 Kb/s in one direction

12. Physical Links

13. Connection Set-up Step 1: Inquiry procedure
Source: inquiry state = sends out inquiry packets
Destination: inquiry scan state
Destination: inquiry response state = sends an inquiry reply to the source

14. Connection Set-up Step 2: Paging Procedure Source pages another device
Destination receives page
Destination replies
Source sends an FHS packet to the destination
Destination sends second reply
Destination and source then switch to the source channel parameters

15. Error Checking 1/3 Forward Error Checking (FEC) 2/3 FEC
Implemented by repeating three bits at a time
2/3 FEC
Generator polynomial is used to encode 10 bit code to 15 bit code
Automatic Repeat Request
requires that the header error and cyclic redundancy checks are okay

16. Whose teeth are blue?
10th century Scandinavian king, Harald Bluetooth managed to unite several unruly kingdoms. Thus, Bluetooth is a reference to the taming of a myriad of unruly competing standards by defining one world-wide specification.