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									  Bluetooth Wireless
     Technology


prepared by: Hossam El-moshrify
Introduction.
Why We use Bluetooth.
Frequency Allocation.
Bluetooth Network Topology.
Overview of the Bluetooth Protocol Architecture.
Error correction code in Bluetooth.
Bluetooth & other Wireless technologies.
Conclusion.
Bluetooth Birth
  Q: What is Bluetooth?   A: Connect without cables
  Q: What does it do?
  A: Cable replacement & wireless ad hoc connectivity
  Q: To whom is it intended?   A: Mobile users

  Q: Where does the name “Bluetooth” come from?
A: Harald Blaatand/ Scandinavia
  Q: Who is Bluetooth?     A: The Bluetooth SIG.
    The Bluetooth Special Interest Group (SIG)
Nine Promoters


           Founders                      Y2K Additions

And over   2000 additional SIG members
              What is Bluetooth
                Good For?
No Wires!
 In the home
 On the move
Personal Area Networking (PAN)
Enabling a collection of YOUR personal devices to
 cooperatively work together
Locality sensitive services
Visibility and access to additional resources, but only
 when they are within range and useful to you
                    Bluetooth @ Home
Digital Camera         NO WIRES
                        Computer


                                                         Scanner


   Inkjet
   Printer
                                                   xDSL
                                                Access Point




Home Audio System                     PDA             Cordless Phone
                                   Cell Phone          Base Station
                        MP3
                       Player
                   On the Move
Car Audio System


                                PDA
                             Cell Phone




                   Headset
                                            Pay Phone
                                          & Access Point

 MP3
Player
                                                 Hotel Phone
                                Laptop          & Access Point
         Bluetooth in Computer Products

Computer devices            Computer applications
•   Laptop computers        • Peripheral connectivity
                               – Printers
•   PDAs/HPCs                  – Scanners
•   Desktop PCs                – Video projectors
•   Broadband access        • Network access
    points                     – Broadband access points
                               – Packet radio cellular phones
    – Ethernet/xDSL/cable   • File synchronization
• Printers                     – Calendars
• Scanners                     – Contact management
• Video projectors          • File transfer
                               – VCards
                               – MP3
                               – Digital pictures
              Bluetooth in Telephone and
                 Consumer Products
Telephone devices        Telephone applications
• Cellular handsets      • Hands free use
• Wireless headsets      • File synchronization
• PSTN access points        – Calendars
   – Payphones              – Contact management
   – Hotel/home phones
                         Consumer applications
Consumer devices         • File transfer
• Digital cameras           – MP3
• MP3 audio players         – Digital pictures
• Home audio systems     • Peripheral connectivity
                            – Keyboard/mouse/remote
                            – Printer
             Bluetooth system is based on a low   cost
        short range radio-link which enables devices to
        communicate wirelessly via short range radio link.

         The Bluetooth is a universal radio interface on the
               GHz frequency band facilitating wireless
    Globally 2.4
  communication of data and voice in stationary and mobile
                           environments.

This chip is tiny, low-power consuming and
can be easily imbedded
 in existing electronic devices.
           Strength of Bluetooth
        1- Cheap Initial costs $ 20 Future target $ 5
2- Tiny It is only 10.2 *14* 1.6 mm. Easy implementation.
                   3- low-power consumption
            Bluetooth radio consumes less than 3% of
    the power compared to that of modern mobile phone .
                 4- It works all over the world
                  Operates on ISM radio band.
                        -Unlicensed band.
   5- Supports point-to-point & point-to-multi-point
                         communication.
 6- High Security - It allows authentication & encryption.
                - Protection against interference.
                         7- High speed .
           - Current speed up to 1 Mbps (723.2 Kbps)
30     300                3           30         300          3          30        300    3          30        300
Hz     Hz                kHz         kHz         kHz         MHz        MHz        MHz   GHz        GHz        GHz


               Voice                                                          VH               SH         EH
     ELF     Frequency         VLF         LF          MF          HF                UHF
                                                                               F                F          F

                                                             890
                                                             MHz

                                              TV
                                                               GSM                       ISM
                                             UHF
                                           470         812              960
                                           MHz         MHz              MHz              2.4
                                                                                         GHz
  Ad hoc client/server
topology, 8 active & up to 256
parked devices per piconet.
  1 master per piconet
“speaking” to slaves via TDM.
  Multiple piconets up to 13
per scatternet.
          Bluetooth Addressing
The following device addresses are used in a
Bluetooth system:
                   BD_ADDR
                   AM_ADDR
                   PM_ADDR
                   AR_ADDR
    The master uses AM_ADDR to address
         each active slave in the piconet
    How Bluetooth Works

            Operational States

D
                    Master
        F                                   N
                    Active Slave    M

                    Parked Slave*
                    Standby*            P
O
                * Low power state
    J
            I                                   Q
                             C
        In the beginning


D
        F                                               N
                    H
                                G           M



                        A                           P
                                        B
O
            E
                            K
    J                                           L
                I                                       Q
                                    C
          Inquiry
Discovering Who’s Out There
                                                    Note that a device can
                                                     be “Undiscoverable”
D
                F                                                     N
                            H
                                        G               M



                                A                                P
                                                B
O
                    E
                                    K
      J                                                     L
                        I                                               Q
                                            C
    10 meters
                Paging
           Creating a Piconet

D
                F                                               N
                            H
                                        G           M



                                A               B           P
O
                    E
                                    K
      J                                                 L
                        I                                       Q
                                            C
    10 meters
             Paging
      A Simplistic Illustration

D
                F                                               N
                            H
                                        G           M



                                A               B           P
O
                    E
                                    K
      J                                                 L
                        I                                       Q
                                            C
    10 meters
      Expanding a Piconet (1)


D
                F           H                                   N
                                        G           M



                                A               B           P
O
                    E               K
      J                                                 L
                        I                                       Q
                                            C
    10 meters
                        Parking


D               F           H                                   N
                                        G           M



                                A               B           P
O
                    E               K
      J                                                 L
                        I                                       Q
                                            C
    10 meters
    Expanding a Piconet (2)


D               F           H                               N
                                    G           M



                            A               B           P
O
                    E           K
      J                                             L
                        I                                   Q
                                        C
    10 meters
            Scatternets


D
        F           H
                                G           M           N



                        A
                                        B
O                                                   P
            E               K
    J                                           L
                I
                                    C                   Q
    Advanced Scatternets


D
        F           H                               N
                            G           M



                    A                           P
                                    B
O
            E           K
    J                                       L
                I                                       Q
                                C
            Bluetooth
8       Applications

    RFCOMM/SDP/TCS/SDP

          L2CAP

            HCI

        Link Manager

       Link Controller
         Baseband

1          Radio
           BaseBand and LM
            The Baseband defines packet formats, physical
            and logical channels and the different
modes of operation which support the transfer of voice
and data.
Audio is needed to transfer voice. The bluetooth specs
follow the GSM recommendations. The Link Manager
(LM) is specified software that handles link authentication,
piconet management, and link setup and configuration.
                 HCI and L2CAP
          The Host Controller Interface (HCI) provides a
          common interface between the Bluetooth host
device (Laptop) and the Bluetooth module.
The Link Layer Control and Adaptation (L2CAP) is
specified to provide a common base for data
communication.
L2CAP distinguishes between the higher level protocols,
and segments and re-assembles packets.
                RFCOMM & SDP
          RFCOMM is a simple transport protocol which
          emulates the serial ports and used for example
in a laptop to printer connection.
RFCOMM provides compatibility with legacy
applications that uses the serial port.
The Service Discovery Protocol (SDP) allows applications
to discover which services are available and to determine
the characteristics of these services
Complete Protocol Stack
 A number of other protocols
  are available for different
  applications, for example:
   OBEX (Object exchange
    protocol) used for file
           transfer.
   TCP/IP used for internet
         applications.
  AT commands to support
  user terminal control. For
 example, entering a PIN for
        Authentication
              Timing & sync.
SCO & ACL links.
          ERROR CORRECTION CODE in
                               BLUETOOTH
Forward Error Correction (FEC) - 1/3 rate 2/3 rate.
Automatic Repeat reQuest (ARQ)
The packet header is always encoded using 1/3 rate FEC.
The payload can either be uncoded or encoded using 1/3 or 2/3.
by a shortened Hamming code (10,15) code
ARQ SCHEME:
DM, DH and the data field of DV packets are transmitted and retransmitted until
acknowledgement of a successful reception is returned by the destination (or timeout is
exceeded).
A cyclic redundancy check (CRC) code is added to the packet to determine the payload
is correct or not.
The ARQ scheme only works on the payload in the packet (only that payload which has
a CRC).
The packet header and the voice payload are not protected by the
ARQ scheme.
               Conclusion
•   Bluetooth technology is the best for (PAN).
•   The Bluetooth is a universal radio interface on the
•   Globally 2.4 GHz frequency
•   Supports point-to-point & point-to-multi-point
    communication
•   Cheap ,Tiny, low-power consumption , High Security ,
    High speed .
•   1 master per piconet “speaking” to slaves up to 7
•    Multiple piconets up to 13 per scatternet.

								
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