Sattam Al-Sahli

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Bluetooth

• Sattam Al-Sahli 237929
• Emad Al-Hemyari 246410

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Contents

• Introduction
• What is Bluetooth?
• The Name Bluetooth?
• Bluetooth Architecture
• Radio Layer
• Base band Layer
• Link Manager Protocol (LMP)
• Logical Link Control and Adaptation Protocol
• Profiles Applications Layer
• Operation between Devices
• Operation between Layers
• MATLAB Simulation
• Conclusion

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Introduction

• Bluetooth is a wireless protocol utilizing
  short-range communications technology for both
  voice and data transmissions over short distances
  from fixed or mobile devices, creating wireless
  personal area networks (PANs).
• It has been named after Harald Bluetooth who was
  the king of Denmark around the turn of the last
  millennium.

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Bluetooth Architecture

• Bluetooth is both a hardware-based radio system
  and a software stack that specifies the linkages
  between layers. This supports flexibility in
  implementation across different devices and
  platforms. It also provides robust guidelines for
  maximum interoperability and compatibility.

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Bluetooth Architecture Radio Layer

• The Bluetooth Radio (layer) is the lowest defined
  layer of the Bluetooth specification.
• The Bluetooth transceiver device operates in the
  2.4GHz ISM band.
• It does the modulation and demodulation of data
  into RF signals for transmission in the air.
• The radio layer describes the physical
  characteristics of the Bluetooth
  receiver-transmitter components.
• These include modulation characteristics, radio
  frequency tolerance, and sensitivity level.

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Bluetooth Architecture Radio LayerTransmitter
Characteristics

• The Bluetooth radio accomplishes spectrum
  spreading by frequency hopping or FDM
• In 79 hops. In France, a 23-hop system is used.
• Displaced by 1 MHz as a guard band.
• Starting at 2.402GHz and finishing at 2.480GHz.
• Power Classes

Type Characteristics
Class 1 Long range (100m) devices, with a max output power of 20 dBm.
Class 2 Ordinary range devices (10m) devices, with a max output power of 4 dBm.
Class 3 Short range devices (10cm) devices, with a max output power of 0 dBm.

• The Bluetooth radio module uses Gaussian
  Frequency Shift Keying.
• Radio Frequency Tolerance of 75 kHz from the
  center freq.

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Bluetooth Architecture Radio LayerReceiver
Characteristics

• Sensitivity level for which the BER 0.1 is met
  in max.
• Out of band blocking is measured with the wanted
  signal 3dB over the reference sensitivity level.
• The maximum usable input level at the receiver
  shall be better than 20 dBm.
• A Receiver Signal Strength Indicator (RSSI)
  provides a power-controlled link that measures
  its own receiver signal strength and determine if
  the transmitter on the other side of the link
  should increase or decrease its output power
  level.

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Bluetooth Architecture Bluetooth Baseband

• Baseband is the physical layer of the Bluetooth.
• It manages physical channels and links apart from
  other services like error correction, data
  whitening, hop selection and Bluetooth security.
• The Baseband layer lies on top of the Bluetooth
  radio layer in the Bluetooth stack.
• The baseband also manages asynchronous and
  synchronous links, handles packets and does
  paging and inquiry to access and inquire
  Bluetooth devices in the area.
• The baseband transceiver applies a time-division
  duplex (TDD) scheme.

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Bluetooth Architecture Bluetooth
Baseband Physical Characteristics

• The channel is represented by a pseudo-random
  hopping sequence hopping through the 79 or 23 RF
  channels.
• Two or more devices using the same channel form a
  piconet.
• There is one master and one or more slave(s) in
  each piconet.
• The hopping sequence is unique for the piconet
  and is determined by the Bluetooth device address
  of the master.
• The channel is divided into time slots where each
  slot corresponds to an RF hop frequency , each
  625 us in length.
• Consecutive hops correspond to different RF hop
  frequencies.
• The time slots are numbered according to the
  Bluetooth clock of the piconet master.
• TDD scheme is used where master and slave
  alternatively transmit.

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Bluetooth Architecture Bluetooth
Baseband Physical Characteristics

• The Baseband handles two types of links
• SCO (Synchronous Connection-Oriented) link a
  symmetric point-to-point link between a master
  and a single slave in the piconet, mainly carries
  voice information.
• ACL (Asynchronous Connection-Less) link a
  point-to-multipoint link between the master and
  all the slaves participating on the piconet,
  packet retransmission is applied.
• Bluetooth has five logical channels which can be
  used to transfer different types of information.
• Data Packet Format L2CAP is packet-based.

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Bluetooth Architecture Link Manager Protocol
(LMP)

• The Link Manager Protocol (LMP) is used to
  control and negotiate all aspects of the
  operation of the Bluetooth connection between two
  devices including setting-up and controlling the
  
• logical transports.
• logical links.
• physical links.
• LMP messages are exchanged over the ACL-C logical
  link that is carried on the default ACL logical
  transport.
• The ACL-C logical link is distinguished from the
  ACL-U (which carries L2CAP and user data) by the
  Logical Link Identifier (LLID) field carried in
  the payload header of variable-length packets.

• The LMP operates in terms of transactions which
  are connected set of message exchanges achieving
  a particular purpose.

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Bluetooth Architecture Logical Link Control and
Adaptation Protocol

• The Logical Link Control and Adaptation Layer
  Protocol (L2CAP) is layered over the Baseband
  Protocol and resides in the data link layer.
• L2CAP provides connection-oriented and
  connectionless data services to upper layer
  protocols with
• protocol multiplexing capability.
• Segmentation.
• reassembly operation.
• group abstractions.
• L2CAP State Machine L2CAP connection-oriented
  channel state machine is described by the
  following figure.

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Bluetooth Architecture Profiles

• The profiles have been developed in order to
  describe how implementations of user models are
  to be accomplished.
• A profile can be described as a vertical slice
  through the protocol stack.
• It defines
• options in each protocol that are mandatory for
  the profile.
• And parameter ranges for each protocol.
• The Bluetooth profile structure and the
  dependencies of the profiles are depicted in the
  following figure.

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Operation between Devices

• It is represented by the connection-oriented data
  channels, where a CID identifies each endpoint of
  the channel.
• These channels are used to support a channel
  group where the CID on the source represents
  one or more remote devices.
• There are also a number of CIDs reserved for
  special purposes, such as signaling.
• This channel is used to
• create and establish connection-oriented data
  channels.
• negotiate changes in the characteristics of these
  channels.

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Operation between Layers

• L2CAP implementations follow the general
  architecture described here
• L2CAP implementations must transfer data between
  higher layer protocols and the lower layer
  protocol.
• Each implementation must also support a set of
  signaling commands for use between L2CAP
  implementations.
• L2CAP implementations should also be prepared to
  accept certain types of events from lower layers
  and generate events to upper layers.

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MATLAB Simulation
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References

• Palo wireless Bluetooth Resource Center
  www.palowireless.com
• Official Bluetooth site aimed at users
• www. Bluetooth .com

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Questions