Bluetooth SIG Proprietary and Confidential 1
Introduction to Bluetooth Technology
Low Energy / Basic Rate / Enhanced Data Rate / High Speed
Muhammad Ulislam, CSR
Bluetooth SIG Proprietary and Confidential 2
Agenda
Introduction to Bluetooth Technology
– Basic Rate/Enhanced Data Rate (BR/EDR)
• High Speed (HS)
– Low Energy (LE)
– Attribute Protocol / Generic Attribute Profile
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Bluetooth Technology Evolution
2007
• V2.1 + EDR - Secure Simple Pairing allows secure device pairing with a button press, numeric entry, numeric compare, and Out of Band
2009
• V3.0 + HS - High Speed Enables applications to use 802.11 MAC/PHY through addition of Generic Alternate MAC/PHY
2010
• V4.0 - Low Energy Enables new applications in different markets including healthcare, sports/fitness, security, home entertainment
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Bluetooth Technology Factsheet Technology Bluetooth BR/EDR/HS Technology Bluetooth Low Energy Technology
Radio Frequency 2.4 GHz ISM 2.4 GHz ISM
Range 10 to 100 meters 10 to 100+ meters
Data Rate 1-3 Mbps (Classic)
>400 Mbps (AMP, 802.11n)
1 Mbps
Nodes/Active Slaves 7 / 16777184 Unlimited
Security 56b E0 (classic)/128b AES (AMP) and
applications layer user defined
128b AES and application layer user
defined
Robustness Adaptive frequency hopping, FEC Adaptive frequency hopping
Latency (from non
connected state)
100ms
<3ms
Regulatory
Acceptance
Worldwide Worldwide
Voice Capable Yes No
Network Topology Scatternet Star-bus
Power Consumption 1 as the reference, x10 for AMP 0.01 to 0.5 (use case dependent)
Service Discovery Yes Yes
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Bluetooth Architecture
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Bluetooth Technology Block Diagram
LE Physical Layer
LE Link Layer
Host Controller Interface
L2CAP
Attribute Protocol
Generic Attribute Profile
Batte
ry
Phon
e A
lert
Fin
d M
e
Pro
xim
ity …
Heart R
ate
BR/EDR Physical Layer
BR/EDR Baseband
BR/EDR Link Controller & Manager
Se
cu
rity
Ma
nag
er
GA
P
Tim
e
Existing BR Protocols (OBEX, RFCOMM, AVDP, etc.)
Existing BR Profiles (A2DP, AVRCP, HFP, etc.)
SD
P
AMP PAL
AMP MAC
AMP PHY
AMP
MGR
AMP BR/EDR Low Energy
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BR Only and LE Only Architecture
Basic Rate RF
Link Manager
L2CAP
RFCOMM Protocols
Serial Port Profile
low energy RF
Link Layer
L2CAP
Attribute Protocol
Generic Attribute
Profile
Bluetooth
Basic Rate
only
Bluetooth
Low Energy
only
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BR/EDR/LE Architecture
Basic Rate RF + low energy
Link Manager
L2CAP
RFCOMM Protocols
Serial Port Profile
Link Layer
Attribute Protocol
Generic Attribute
Profile
Basic Rate RF
Link Manager
L2CAP
RFCOMM Protocols
Serial Port Profile
low energy RF
Link Layer
L2CAP
Attribute Protocol
Generic Attribute
Profile
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Bluetooth Technology Basics
Basic Rate / Enhanced Data Rate / High Speed
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Bluetooth BR/EDR Radio (Time)
Time is divided into 625 uS “slots”
Data is exchanged via “Packets” lasting one or
more slot
– Packets consists of Access Code, Header and Payload
– EDR introduced Guard, Sync and Trailer
Two types of data exchange “mode”
– Asynchronous Connection-oriented logical transport (ACL)
– Synchronous Connection-oriented link (SCO), Enhanced
SCO (eSCO)
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Bluetooth BR/EDR Discovery
One device “looks” for others (Sends ID
Packets)
One or more other devices listens
(Discoverable)
– When acceptable packet is received, replies
“Searching” device may continue with this device
or continue looking
When desired device is found, connection
process begins
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Bluetooth BR/EDR Connection Establishment
One device initiates connection
Other device has to be willing to accept a
connection
Initiator “pages” the desired device using an ID
packet derived from the LAP of the desired
device
Once listening device hears the ID packet with
it’s address, it replies
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Piconet
One Master and up to 7 active slaves
Master controls communication
No slave-to-slave communication
Master has to ensure not to “starve” slaves
M
S1
M
S S2 S3
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Scatternet
Two (or more) “joined”
piconets
Master of one piconet
is slave in another
No direct
communication
between slaves in one
piconet with those in
the other S1
S
M1
S2 S3
M2
S4
S5
S6
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Interference Management
Adaptive Frequency Hopping (AFH)
– Designed to reduce interference between wireless
technologies sharing the 2.4 GHz spectrum
– Works within the spectrum to take advantage of the
available frequency
– Detects other devices in the spectrum and avoids
frequencies in use
Provides users with optimal transmission
performance even if utilizing other technologies
within the same spectrum
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Bluetooth Channels – SCO & eSCO
Synchronous Connection Oriented (SCO)
– Used for voice data
– Utilized reserved timeslots with no retransmission but may
use forward error correction
– Four packet types (all single slot): HV1, HV2, HV3, and DV
• Enhanced SCO (eSCO) adds retransmissions
– BR packet types: EV3 (1 slot), EV4 and EV5 (3 slot)
– EDR packet types: 2-EV3 (1 slot), 2-EV5 (3 slot), 3-EV3 (1
slot), 3-EV5 (3 slot)
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Bluetooth BR/EDR Channels - ACL
Asynchronous Connection-Less (ACL)
– Used for data connections
– Throughput is best-effort and is impacted by other factors
like the number of devices in the piconet
– Packets
• DM1: 1 slot, 18 bytes with FEC and CRC
• DH1: 1 slot, 28 bytes no FEC with CRC
• AUX1:1 slot, 30 bytes no CRC
• DM3: 3 slots, 123 bytes with FEC and CRC
• DH3: 3 slots, 185 bytes no FEC with CRC
• DM5: 5 slots, 341 bytes with FEC with CRC
• DH5: 5 slots, 226 bytes no FEC with CRC
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Bluetooth BR/EDR Power Classes
Three Power Classes:
– Class 1: 0dBm to +20dBm (1mW to 100mW)
– Class 2: -6dBm to +4dBm (250µW to 2.5mW)
– Class 3: <0dBm (<1mW)
Power classes can be used to estimate
approximate range:
– Class 1: 100 Meters
– Class 2: 10 Meters
– Class 3: <10 Meters
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Bluetooth High Speed Technology
Leverages existing radio technology
– 802.11 a,b,g,n
– Backward compatible with legacy Bluetooth devices
It’s Bluetooth wireless technology, only faster
– Consumers benefit from enhanced data rates without
changing the way they utilize Bluetooth technology today
Leverages existing 802.11 device capabilities
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Bluetooth Technology Basics
Low Energy
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Physical Channels
ISM band split into 40 channels of two types
– Advertising Channels
– Data channels
Advertising Channels
– Frequencies: 2402 (37), 2426 (38), 2480 (39)
– Usage
• Discovering devices
• Initiating a connection
• Broadcasting data
Data Channels
– Frequencies: 2404-2424 (0-10), 2428-2478 (11-36)
– Usage: Communicating between connected devices
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Bluetooth Low Energy Frequency Plan
Lower guard band of 2MHz, upper guard band of 3.5MHz
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L2CAP Channel Types
Higher Level Protocol Multiplexing
Packet Segmentation and reassembly
L2CAP in Bluetooth low energy operates in
Basic Mode
– Offers only fixed channel types
Channel Type Local CID (sending) Remote CID (receiving)
Attribute Protocol 0x0004 (fixed) 0x0004 (fixed)
Signaling 0x0005 (fixed) 0x0005 (fixed)
Security Manager
Protocol
0x0006 (fixed) 0x0006 (fixed)
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Generic Access Profile (GAP)
Defines procedures for:
– Discovering identities, names, and basic capabilities
– Creating bonds
– Exchange of security information
– Establishing connections
Defines Advertising and Scan Response Data formats
All profiles are built upon GAP
Defines profile roles
– Broadcaster – sends non-connectable advertisement and never connect
– Observer – listens to advertisement packets but never connect
– Peripheral – Always take the role of slave
– Central – Always take the role of master
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Bluetooth Technology Basics
Attribute Protocol & Generic Attribute Profile
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Attribute Protocol (ATT)
Client Server Architecture
– servers have data
– clients request data to/from servers
Servers expose data using Attributes
Server Client
Data Requests
Responses Data
Data
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Generic Attribute Profile (GATT)
• Built on top of ATT
• Provides a framework for developing profiles
• A profile is composed of one or more services
• A service is composed of characteristics or references to other services
• Each characteristic contains a value and may contain optional information about the value
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GATT-Based Profile Specifications
Profile specifications
– Use case
– Behaviors
– Discovery Procedures
– Connection Parameters (slave latency, conn Interval) etc
– Profile Roles
Service specifications
– Characteristics (Mandatory, Optional)
– Characteristics Properties (Broadcast, Control Point etc)
Characteristics specifications
– Specify structure of value – Eg: Alert Level – 1 byte
– Permissible values – Eg: 0 – No Alert, 1 – Medium Alert, 2 – High Alert
– Permissions – Read/Write
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Profiles Overview
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What are Traditional Profiles?
HOST GOEP (OBEX)
L2CAP
RFCOMM
CONTROLLER
Link Manager
Baseband
Radio (PHY)
AVDTP AVCTP
PBAP
HFP A2DP
HID
AVRCP
OPP
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What are GATT-Based Profiles?
HOST
Generic Attribute Profile (GATT)
Attribute Protocol (ATT)
L2CAP
CONTROLLER
Link Manager
Baseband
Radio (PHY)
HID over
GATT
Sports and
Fitness Consumer
Healthcare
Proximity,
Find Me,
Alert
Notification
Battery,
Time, Device
Information
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GATT-Basics
Generic Attribute Profile
First available in v4.0
Designed to enable new
market of low power
devices
– Optimized for low duty
cycle use and small
packets
– Key to power reduction
Mandatory for low energy,
but Optional for BR/EDR
Generic Access Profile (GAP)
Generic Attribute Profile (GATT)
Attribute Protocol
(ATT) Security Manager
Logical Link Control and Adaptation
Protocol (L2CAP)
Host Controller Interface (HCI)
Physical Layer
Link Layer (LL) Direct Test Mode
Applications
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GATT Client-Server Architecture
Servers contain data
Clients request data from Servers, write data to
Servers, or initiate actions
Server Client
Data Requests
Responses Data
Data
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GATT Service Structure
Services generally embedded in low power sensors
– Example: Heart Rate Service + Battery Service
Downloadable apps can incorporate profiles to control and get data from sensors
– Key to rapid deployment to the masses
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Recent Traditional Profile Updates
Bluetooth SIG Proprietary and Confidential 36
Telephony
Hands Free Profile (HFP)
– HFP v1.6 adds
• Individual Indicator Activation
– Select indicators that you want (Battery level, network reception,…)
– Preserves battery life
• Wide Band Speech Support
– 16KHz sampled audio instead of 8KHz
– Useful over networks which enable it as well.
– Better voice recognition success rate
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Audio Streaming
Advanced Audio Distribution Profile (A2DP)
– v1.3 adds Delay Reporting
Audio Video Remote Control
– AVRCP v1.4/v1.5 adds the Media Browsing Channel
• Browse your MP3 player’s music and playlists directly from your car
user interface.
Audio
Delay (200ms)
Delay 60ms Delay 200ms (Buffer) +140ms
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Generic Object Exchange Profile v2.0
Better Quality of Service (QoS)
– Service multiplexing is now entirely done by L2CAP
Better throughput
– Flow Control, Segmentation & Reassembly are done by L2CAP Enhanced Retransmission Mode (ERTM)
Improved support for AMP (High Speed)
– Channels can move over a different MAC/PHY without moving the whole RFCOMM stack
L2CAP
RFCOMM
GOEP 1.1
MAP PBAP FTP BIP OPP
L2CAP
RFCOMM
GOEP 1.1
MAP 1.2 PBAP 1.1
GOEP 2.0
FTP 1.2 BIP 1.1 OPP 1.2
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Generic Navigation Satellite System Profile
Generic Navigation Satellite System (GNSS)
– Create a wireless serial link so a device can share its GPS position data using the NMEA-0183 protocol.
Positioning Data (NMEA-0183)
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3D Synchronization Profile
3D Synchronization Profile v1.0
– The user’s stereoscopic 3D experience is delivered by
showing different images to the left and right eyes.
– The 3D glasses use shutter synchronization information
transmitted from the 3D display to control the shutters
such that the left image is shown only to the left eye and
the right image is shown only to the right eye, when 3D
content is being displayed
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Recent GATT-based Profiles and Services
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Initial GATT-Based Profiles/Services (1/2)
Common Profiles and Services
– Device Information Service (DIS)
– Time Profile (uses Current Time Service, Next DST
Change Service, Reference Time Update Service)
– Battery Service
– Scan Parameters Profile/Service
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Initial GATT-Based Profiles/Services (2/2)
Device-specific Profiles and Services
– Proximity Profile (uses Immediate Alert Service, TX Power
Service, Link Loss Service)
– Find Me Profile (uses Immediate Alert Service)
– Alert Notification Profile (uses Alert Notification Service)
– Phone Alert Status Profile (uses Phone Alert Status Service)
– Health Thermometer Profile (uses Health Thermometer Service
and DIS)
– Heart Rate Profile (uses Heart Rate Service and DIS)
– Blood Pressure Profile (uses Blood Pressure Service and DIS)
– HID over GATT Profile (uses HID Service, Scan Parameters
Service, Battery Service and DIS)
Bluetooth SIG Proprietary and Confidential 44
Recent GATT-based Profiles/Services
Recently Published Profiles and Services
– Glucose Profile (uses Glucose Service and Device
Information Service (DIS))
– Cycling Speed and Cadence Profile (uses Cycling Speed
and Cadence Service)
– Running Speed and Cadence Profile (uses Running
Speed and Cadence Service)
– Cycling Power Profile (uses Cycling Power Service, DIS,
Battery Service)
– Location and Navigation Profile (uses Location and
Navigation Service, DIS, Battery Service)
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Glucose
Sends blood glucose measurement to Collector after each measurement if available
– Users typically take 1-8 measurements per day
– Once connected, Collector requests only the data that it needs
Data is required to be compatible with internationally recognized data standards
– Measurement history needs to be uploaded to PHR or shared with healthcare provider as part of EHR
Addresses market of 300M+ with diabetes worldwide
Published April 2012
Personal
or
Caregiver
Collector
Blood
Glucose
Sensor
Blood Glucose data
+ data Context (O)
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Cycling Speed and Cadence
Sends raw Wheel Event data and Crank Event data to Collector ~every second while user is cycling
– Collector is pre-configured to know wheel circumference and calculates Speed, Cadence and Distance
Can be used with separate sensors or combination sensors
Addresses huge market of cyclists
Published August 2012
Collector
Cadence Sensor
Speed Sensor
Collector Wheel Event data and/or
Crank Event data
Speed and
Cadence
Sensor
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Running Speed and Cadence
Sends Speed, Cadence, Stride Length and Total
Distance data to Collector ~every second when
user is walking or running
Can be used with Heart Rate and other sports
sensors
Addresses huge market of runners/walkers
Published August 2012
Collector Speed + Cadence +
Stride Length (O) + Distance (O)
RSC
Sensor
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Cycling Power
Cycling Power sensor sends data to user’s
Collector to help optimize pedaling efficiency
Collector Cycling Power data Cycling Power
Sensor
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Location and Navigation
1) Positioning Sensor sends location information to
Collector which logs hiking data (‘tracks’)
2) Collector sends user-defined waypoint (i.e. the next
destination) to positioning sensor which sends
location, bearing and heading to Collector to guide
user
Sports
Watch Positioning/Activity Data
Waypoint Coordinates
Sports
Watch Positioning/Activity Data
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