bluetooth & bluetooth low energy internals
TRANSCRIPT
BluetoothIr. Davy Jacops Nov 2015
Technicolor Intro Bluetooth Market Tech Side Future Q&A
Bluetooth: Agenda
Intro Bluetooth Market Tech Side Future Q&A
Bluetooth: Agenda
Q&A Short range wireless communications technology Personal Area Networking “PAN” Applications
Cable replacement Voice & Data access points Ad-hoc networking
Key features Robustness Low power Low cost
Bluetooth Intro
Bluetooth Intro: History 1998:
BT SIG formed:: Ericsson, Toshiba, Intel, Nokia, IBM
Name “Bluetooth” officially adopted 1999:
Core spec 1.0 released First BT unplug fest BT technology “Best of show
technology award” at COMDEX 2000:
First BT enabled mobile phone First BT “single chip”
2001: First BT enabled printer First hands free car kit BT SIG is formed as non profit, non
stock corporation 2002:
>500 BT qualifed products First BT keyboard & mouse combo
2003: Adoption of core spec 1.2
2004: Adoption of core spec 2.0 + EDR
2005: shipment of 5M BT chipsets per week
2006: First BT enabled watch, > 1B BT
devices shipped SIG announces integration of BT and
WiMedia UWB 2007: First BT enabled TV shipped 2008: > 2B BT devices shipped in 10
years 2009: BT Core spec 3.0 HS 2010:
BT4.0 core spec adopted (BLE) PTS 4.1 launched incl BLE test suites
2011: “BT Smart” & “BT Smart” ready brands 29 new BT 4.0 profiles
2012: new profiles running & cycling data monitoring
2013: BT 4.1: IoT Native BT support in Android
2014 BT 4.2: IP connectivity Core spec 2.772 pages
Bluetooth Intro: FlavorsFlavor Subset name(s) Core
spec version
Max Data rate
Voice
Spec
Bluetooth “Classic”
Basic Rate (BR) 1.x 721.2 kbps V 1999Enhance Data Rate (EDR)
2.x + EDR
2.1 Mbps V 2004
Bluetooth “High Speed”
High Speed (HS)Alternate Mac PHY (AMP)
3.x + HS 54 Mbps (802.11 AMP)
V 2009
Bluetooth“Low Energy”
Ultra Low Power (ULP)Bluetooth Low Energy (BLE)BT SmartBT Smart Ready(Wibree)
4.x 1 Mbps X 2010
Bluetooth Intro: “Bluetooth”?
The idea for the Bluetooth name came from Jim Kardach of Intel, who was reading a historical novel about Vikings and King Harald Blåtand at the time.
The name is the link to the distant past. “Bluetooth” is derived from the nickname of King Harald Blåtand a Dane who (somewhat violently) brought together people in what are now Denmark, Norway, and Sweden into a single kingdom.
King Harald reigned from 958 to 986 and got his nickname from his penchant for eating blueberries.
Intro Bluetooth Market Tech Side Future Q&A
Bluetooth: Agenda
Personal AreaBluetooth
Local AreaWi-Fi 802.11
Wide AreaMobile 3G-4G
LTE
Short range communications suchas mobile / PC accessories
CABLE REPLACEMENT
The center of the connectedhome / enterprise
For applications that demandubiquitous coverage and high reliability
Bluetooth MarketPositioning
10.000+ new BT enabled products listed in 2014 24% up from 2013
3B devices shipped in 2014 90% penetration in all mobile phones Huge growth
Smart home Consumer electronics
Bluetooth MarketBasic Figures
Source: Bluetooth SIG 2014 annual report
Bluetooth MarketShipments
Bluetooth enabled device shipments worldwide (billion units)
Bluetooth MarketGrowth
Bluetooth Smart growth 2013-2014Source: ABI Research
Bluetooth MarketSIG member Companies
Bluetooth SIG members Monthly increaseSource: Bluetooth SIG
Bluetooth MarketWorldwide Press Coverage
Source: Bluetooth SIG
Intro Bluetooth Market Tech Side Future Q&A
Bluetooth: Agenda
Intro Bluetooth Market Tech Side
Basic Rate (BR) & Extended Data Rate (EDR)
Bluetooth Low Energy Future Q&A
Bluetooth: Agenda
Universal Wireless Standard Small & Cheap Low Power Wireless (<0.1W active power)
2.4GHz ISM band Spread Spectrum Frequency Hopping
Avoid interference in ISM 1600 hops/s (625µs time slots) Pseudo random sequence based on master BD address
TDD for send / receive Modulation
BR: GFSK-Gaussian Frequency Shift Keying EDR: PSK-Phase Shift Keying BLE: GSFK
1 – 100mW Range: up to 100m Voice & Data Secure BD address: 48 bit IEEE registered
Bluetooth: Tech Side
BT SIG documents Core Specification
How the tech works Bluetooth protocols
Profiles How the tech is used How different parts of the spec shall be used to
fulfill a desired function
Bluetooth: Tech Side
Bluetooth Core SpecificationBR/EDR Piconet
Piconet: • Set of devices connected in ad hoc fashion• 1 Master, 1..7 Slaves• Master determining hopping pattern• Slaves have to synchronize• Each piconet has a unique hopping
sequence• Participation in piconet = synchronization
to hopping sequence• >200 can be parkedM=Master
S=SlaveP=Parked (deepest sleep)SB=Standby
Source: Free University Berlin
Bluetooth Core SpecificationBR/EDR Forming a Piconet
• Master gives slaves its clock and BD addr.
• Hopping pattern:• Determined by master BD (48bit)• Hopping phase determined by
clock• Addressing
• AMA 3 bit• PMA 8 bit
M=MasterS=SlaveP=Parked (deepest sleep)SB=Standby
Source: Free University Berlin
Bluetooth Core SpecificationBR/EDR Multi-Slave timing
Source: Bluetooth Specification version 4.2
Bluetooth Core SpecificationBR/EDR Scatternet
• Linking of multiple co-located piconets through sharing of common master or slave devices
• Communication between piconets• Devices jumping back and forth
between piconetsM=MasterS=SlaveP=Parked (deepest sleep)SB=Standby
Source: Free University Berlin
Bluetooth Core SpecificationBR/EDR Freq Selection
Source: Free University Berlin
Bluetooth Core SpecificationBR/EDR ACL Packet Types
Source: Bluetooth Specification version 4.2
Bluetooth Core SpecificationBR/EDR Link Control Packet Types
Source: Bluetooth Specification version 4.2
Bluetooth Core SpecificationBR/EDR SCO Packet Types
Source: Bluetooth Specification version 4.2
Bluetooth Core SpecificationBR/EDR Protocol Stack
Source: Free University Berlin
• OBEX: Object Exchange• TCS BIN: Telephony Control
Binary• BNEP: Bluetooth Network
Encapsulation protocol• SDP: Service Discovery Protocol• RFCOMM: Radio freq comm.
Bluetooth Core SpecificationBR/EDR Robustness
Source: Free University Berlin
Bluetooth Core SpecificationBR/EDR Adaptive Freq Hopping
Source: Design-Reuse.com AFH
TimeWiFiBT
Bluetooth Core SpecificationBR/EDR Adaptive Freq Hopping
Source: Design-Reuse.com AFH
TimeWiFiBT
Profiles represent default solutions for a certain usage model Vertical slice through the protocol stack Basis for interoperability
Examples Serial Port Profile Headset Profile Dial-up Networking Profile Synchronization Profile …
Bluetooth Core SpecificationBR/EDR Profiles
Source: Bluetooth Specification version 4.2
Bluetooth Core SpecificationBR/EDR Profiles Example: Headset
Source: Bluetooth Developer Portal & Bluetooth Headset Profile Specification V12
Bluetooth Core SpecificationBR/EDR Profiles Example: Headset
Source: Bluetooth Developer Portal & Bluetooth Headset Profile Specification V12
Example headset scenario: Incoming audio connection In-band ring tone
Bluetooth Core SpecificationBR/EDR Profiles List
Source: Bluetooth Developer Portal
Intro Bluetooth Market Tech Side
Basic Rate (BR) & Extended Data Rate (EDR)
Bluetooth Low Energy (BLE) Future Q&A
Bluetooth: Agenda
BLE targets even more: Ultra-low peak, average and idle mode power
consumption (1/2 to 1/100 of BR) Lower memory requirements Ability to run for year(s) on coin cell batteries Lower cost Enhanced Range
Drawbacks No voice Lower data rates
Bluetooth Core SpecificationBluetooth Low Energy - Intro
Source: BLE Developers Handbook – Robin Heydon
BLE – how to reach the cost advantage Low cost ... needs high volume ... needs very successful products ... largest volume consumer electronics is cell phone / smart phone ... reason of success of BT classic …BLE will build on attach rate of BT classic > 1B devices in a couple of years Roll out already ongoing
Opens new markets Phone accessories Other devices such as Home Automation, TV, PC, BT classic upgrades
Bluetooth Core SpecificationBluetooth Low Energy - Intro
Source: BLE Developers Handbook – Robin Heydon
Bluetooth Core SpecificationBluetooth Low Energy - Intro
Source: BLE Developers Handbook – Robin Heydon
Bluetooth Core SpecificationBluetooth Low Energy - Intro
Source: BLE Developers Handbook – Robin Heydon
Low Energy: how low is “low”? “Few years on button-cell battery” ~ 230 mAh at 3 V Power a human being for 20s
BLE Asymmetric Design Central “Bluetooth Smart Ready” –
Peripheral “Bluetooth Smart” Advertiser – Scanner Slave – Master Server – Client (Attribute protocol)
Advertisers / Slaves / Servers Low memory / processing power / ultra low power
consumption / Low cost
Bluetooth Core SpecificationBluetooth Low Energy - Intro
Source: BLE Developers Handbook – Robin Heydon
BLE – PHY Internals GFSK Clock period = 1 s𝛍 40 Channels -20dBm < Tx power < 10dBm Rx sensitivity: -70dBm or better Distance: 2.5m … 40m ... 250m
Bluetooth Core SpecificationBluetooth Low Energy - PHY
Source: BLE Developers Handbook – Robin Heydon
BLE – Link Layer Standby: Inactive Advertising: Transmit
Advertising packets Broadcast packets
Scanning: Receive advertising packets
Initiating: Initiate a connection
Connected: Sub-states: Master or Slave
Bluetooth Core SpecificationBluetooth Low Energy - LC
Source: BLE Developers Handbook – Robin Heydon
Bluetooth Core SpecificationBLE – BT Classic Interop
Source: BLE Developers Handbook – Robin Heydon
BLE – Adaptive Frequency Hopping 37 channels Next Frequency:
hop = 5…16
Bluetooth Core SpecificationBluetooth Low Energy - AFH
Source: BLE Developers Handbook – Robin Heydon
Hop = 13
BLE – AFHAdaptiveFrequencyHopping
Bluetooth Core SpecificationBluetooth Low Energy - AFH
Source: BLE Developers Handbook – Robin HeydonAFH enabled AFH disabled
BLE – Connection Setup Connection request packet includes (among others):
Access Address to be used in the connection CRC initialization value Transmit window size Transmit window offset Connection interval Slave latency Supervision timeout Adaptive frequency-hopping channel map Frequency-hop algorithm increment Sleep clock accuracy
Bluetooth Core SpecificationBluetooth Low Energy
Source: BLE Developers Handbook – Robin Heydon
Connectionless model No cable replacement anymore Transient connections
Quickly create connection Do something & Disconnect
E.g. State notification every 5 minutes Only requires radio activity < 1s per day Radio OFF 99.999% of the time
Single connect / data / disconnect in about 3ms
Bluetooth Core SpecificationBluetooth Low Energy
Source: BLE Developers Handbook – Robin Heydon
Bluetooth Core SpecificationBluetooth Low Energy: Architecture
Source: BLE Developers Handbook – Robin Heydon
Characteristics (UUID) & Services
Discovery, connection, bonding, privacy
Types of profiles and how they are used
Rules for accessing data (att=labeled bits of data)
Mux, Flow control
HCI
Advertising, Scanning, conn mgt, CRC
GFSK / 1 bit = 1 us
Bluetooth Core SpecificationImplementation: Chipset Solutions
Source: BLE Developers Handbook – Robin Heydon
Single Chip
2 Chip 2 Chip
3 Chip
Bluetooth Core SpecificationBLE: Attribute Protocol
Source: BLE Developers Handbook – Robin Heydon
Bluetooth Core SpecificationBLE: Attribute Protocol
Source: BLE Developers Handbook – Robin Heydon
Bluetooth Core SpecificationBLE: Attribute Protocol
Source: BLE Developers Handbook – Robin Heydon
Bluetooth Core SpecificationBLE Profiles List
Source: Bluetooth Developer Portal
Intro Bluetooth Market Tech Side Future Q&A
Bluetooth: Agenda
“The best way to predict the future is to invent it.”Alan Kay
BluetoothFuture
Source: Bluetooth Developer Portal
BluetoothFuture
Source: Broadcom CES Blog Jan 2015
Bluetooth Future:Bluetooth “Smart”
“More Than 30 Billion Devices Will Wirelessly Connect to the Internet of Everything in 2020”ABI Research
Bluetooth Future:Bluetooth 4.x BLE and beyond
Source: Bluetooth SIG Brands
Bluetooth Future:Bluetooth “Smart Ready”
Source: Bluetooth SIG: Bluetooth Smart Ready devices
….
39 devices• Apple iPad, iPhone, MacBook, Mac mini• Google OnHub• …
Bluetooth Future:Bluetooth “Smart”
Source: Bluetooth SIG: Bluetooth Smart devices
….
172 devices
Bluetooth “Mesh” networking Extend range Control up to 64k BLE devices 100m .. Several
km Device grouping
Proposed by CSR (now Qualcomm) Expected release: 2016
Bluetooth Future:Bluetooth “Mesh”
Source: Bluetooth SIG: Bluetooth Smart devices
Intro Bluetooth Market Tech Side Future Q&A
Bluetooth: Agenda
BT core specification: TODO SIG Annual report 2014: https://www.bluetooth.org/en-us/Documents/Annual_Report_2014.
pdf SIG history: http://www.bluetooth.com/Pages/History-of-Bluetooth.aspx ABI research: https
://www.abiresearch.com/press/more-than-30-billion-devices-will-wirelessly-conne/ ABI research: https://www.abiresearch.com/market-research/service/internet-of-everything
/ Bluetooth Security: https://
courses.cs.washington.edu/courses/cse466/01au/Projects/BluetoothSecurity.ppt Bluetooth Low Energy: The Developer’s Handbook – Robin Heydon
http://www.amazon.com/Bluetooth-Low-Energy-Developers-Handbook/dp/013288836X Android BLE development API
http://developer.android.com/guide/topics/connectivity/bluetooth-le.html iOS BLE development API
https://developer.apple.com/library/ios/documentation/NetworkingInternetWeb/Conceptual/CoreBluetooth_concepts
References