1. What is Blue Tooth ? Blue tooth is a cable replacement technology that can be used to connect almost any device to any other devices. Blue tooth is the implementation of a protocol defined by IEEE 802.15 standard. WPAN Wireless Personal Area Network.

2.  Short Range wireless (10 – 100 m).  Low Power Transmission (1 – 100 m W).  Lower Data Rates < 1 Mbps like audio, text, graphics & even Video  Using 2.4 GHz ISM Band.  FHSS over 79 Chls (1 MHz each), 1600 hops/sec, to avoid freq selective fading & provide security.  Non Line Of sight communication. What is Blue Tooth ?

3. Blue Tooth Logo showing Blue tooth enabled devices i.e. home appliances, Laptop/PDA/ Palm top/Desktop etc

4. History Of Blue Tooth  Blue Tooth Technology was originally started by the Eriksson company. It is named for Blaatand King of Denmark (Blue Tooth in English).  SIG (Special Interest Group) in May 1998  Founding Members :- Erikson, Toshiba, Intel, IBM, Nokia.  Now all of biggest companies in Telecom Business joined the SIG – 1500 Members.

5. Blue Tooth Architecture Blue Tooth defines two types of Networks. 1- Pico Nets (Adhoc Network )  A small net.  A Piconet can have up to 8 stations – one of which is called Master, the rest are called Active Slaves.  All the stations synchronize their clocks / hoping sequences with (as set by Master).  Pico Net can have only one Master Station.

6. Parked Slave Although a Pico net can have a max of seven slaves, an additional slaves can be in parked state. A Slave in Parked state is synchronized with Master but cannot take part in communication until it is moved from the parked state in to active state. Pico Net

7. The communication between the master & the slaves can be one to one & one to many. A Slave may only communicate with Master& may only communicate when granted permission by the Master.

8. Scatter Net  Piconets can be combined to form what is called a Scatter Net. A slave station in one piconet can become the master in another piconet.  This station can receive messages from the master of first piconet (as a slave) and acting as a master deliver it to slaves in the second piconet.  A station can be a member of two piconets.

9. Co-existence Of BT in Wi-Fi N/Ws  Wi-Fi Networks 802.11 use also 2.5 GHz Band same as used in Blue tooth Networks.  There is a possible chance of interference with each other.  Can be controlled by reducing transmit power of Blue tooth devices ( 1-100 mW) while in case of Wi-Fi transmitters (1-4 W).

10. Blue Tooth Applications Internet Bridge: Use your portable PC to surf internet any where. Whether you are connected wirelessly through mobile fone or through a wired connection (PSTN, xDSL, ISDN)

11. Blue Tooth Applications Data Access Point: LAN access replaces a cable with a blue tooth link.

12. Interactive Conference: In meeting /conference, you can share information instantly with other participants. Users are able to transfer files a business cards, fone records or larger files between them. You can also operate a projector remotely without wire connectors. NLOS Environment Blue tooth can replace a wired /IR link to transferring files b/w devices. Professor & class example. Blue Tooth Applications

13. Delayed Messages/Emails: Compose email on yours PC while you are in plan. When you land & switch yours mobile fone ON, the messages will be sent immediately. Cordless Desktop Connect your Laptop/Desktop cordlessly to printer, scanner, keyboard & mouse. Blue Tooth Applications

14. The Ultimate Headset : The blue tooth headset can create an audio link to other Blue tooth equipped devices. Make & receive calls from headset connected remotely to cell fone/PSTN.

15. Automatic Synchronization Blue tooth can provide convenient file synchronization between several devices. For Example :- Office desktop & PDA, Home Desktop & PDA. Blue Tooth Applications

16. Health Care Center: Monitoring devices can communicate with sensor devices in IC Units. Security Devices : Installed Sensors i.e. door opening, smoke detector for security purposes may communicate with Main Room. Blue Tooth Applications

17. Misc Applications: A BT enabled PDA can be used for accessing flight information at an airport. Ordering of an electronic menu at a Resturant. Obtaining information about players when attending a sport event. Blue Tooth Applications

18. In shopping Mall, it will provide all information about items to be sold. Blue Tooth Home Network: When you are entering in yours home, you can open garage door, home door electronically, turn on home appliances i.e oven, lights, fans, ACs. To set the alarm Joy sticks & Loud speakers. Blue Tooth Applications

19. RF Baseband Audio Link Manager L2CAP Data Control Blue Tooth Layers RFCOMM SDP IP Applications

20. Blue Tooth Layers Radio Layer  Equivalent to Physical layer of Internet Model  Deals with Radio specifications  2.4 GHz Band  FHSS Used at Radio Layer  Frequency hoping shift keying method.  Blue tooth hops 1600 times /sec,625 usec  fc = 2402 + n n= 0,1,2 ………  Modulation GFSK Gaussian Frequency Shift Keying  Bit 1 is representing by a freq dev above carrier  Bit 0 is representing by a freq dev below carrier

21.  Modulation GFSK Gaussian Frequency Shift Keying  Bit 1 is representing by a freq dev above carrier  Bit 0 is representing by a freq dev below carrier.  Blue Tooth Transmitter classes  Class-1 : 100 mW, Dist = 100 m  Class-2 : 1 mW, Dist = 1m  Topology :  Up to simultaneously links in a logical star.  Pico net access TDD-TDMA  Carrier spacing = 1 Mhz Blue Tooth Layers

22. Base band Layer It is equivalent to MAC layer in LANs. Access Method is FH-TDD-TDMA. Half duplex, At a time in one direction. Master & Slave communicate with each other using time slots. Slaves cannot communicate with each other. At a time, one freq is used either master sends frame to slave or vice versa. Blue Tooth Layers

23. FH-TDD-TDMA. Advantage Of FH-TDD-TDMA It provides resistance to interference & multipath effects. It provides a form of multiple access among co-located devices in different piconets

24. Single Slave Communication m s1s1 s2s2 625 sec f1 f2 f3 f4 1600 hops/sec f5 f6 FH/TDD

25. Single Slave Communication Master uses even slots (0,2,4…) & slaves uses odd numbered slots (1,3,5,…). In slot 0, master sends and slave receives. In slot 1, slave sends and master receives. And Cycle is repeated.

26. Multi Slave Communication  For more than one slave.  The Master uses even number slots, but slave sends in the next odd numbered slot if the packet in the previous slot was addressed to it.  All Slave listens on even numbered slots but only one slave sends in any odd numbered slot.  It is similar to Poll/Select operation. When the master selects a slave, it polls it & next time slot is reserved for the poll station to send its frame.  If no frame to send, the channel will be silent.

27. Multi Slot Frame A frame in Base band layer can be one of three types: One Slot Three Slot Five Slot Total Frame time is 625 u sec. 259 u sec is required for hopping & control mechanism. Actual data time in frame = 625 – 259 = 366 us mean 366 bits. For A Three slots, 3 x 625 – 259 = 1616 bits.

28. For Five slot frame, 5x 625-259 = 2866 bits. It remains at the same hop ( at the same carrier freq). Multi slot packets

29. m s1s1 s2s2 625 sec f1 f4 f5 f6 FH/TDD Data rate depends on type of packet

30. Packet Format Access code Header Payload 72 bits 54 bits 0 - 2745 bits Synchronization identification Filtering Address Packet Type Flow control ARQ SEQN HEC Error correction 1/3 rate FEC 2/3 rate FEC ARQ scheme for the data Smaller than an ATM cell ! Notice that there is no protocol type field

31. Physical Link Types  Synchronous Connection Oriented (SCO) Link slot reservation at fixed intervals slot reservation at fixed intervals No ARQ, No CRCNo ARQ, No CRC FEC (optional)FEC (optional) 64 Kbps64 Kbps

32. Asynchronous Connection-less (ACL) Link Asynchronous Connection-less (ACL) Link Polling access methodPolling access method ARQ, CRCARQ, CRC FEC (optional)FEC (optional) Symmetric data rate 108 - 433 KbpsSymmetric data rate 108 - 433 Kbps Asymmetric data rate up to 723 KbpsAsymmetric data rate up to 723 Kbps Physical Link Types

33. L2CAP Layer Logical Link Layer & Adoption Protocol : It is roughly equivalent to LLC sub layer. It is used for data exchange on an ACL Link. DutiesMultiplexing Segmentation & Reassembly QoS Group Management.

34. Blue Tooth Material 1-Slides&2-Book Data Communication & Networking Ch-15 By Forouzan