1. Bluetooth

2. Bluetooth Basic idea: cable replacement
Forget Plug and Play - just Play
1Mbps(Sync), 723kbps(Async)
2.4GHz ISM band
3 voice channels
8 participants in a piconet
Introduced by Ericsson Laboratory
Bluetooth SIG
Serve as the baseline of IEEE standard for WPAN

3. Application Examples
Bluetooth

4. Bluetooth Application Domains
Landline
Data/Voice Access Points
Cable Replacement
Personal Ad-hoc Networks
Bluetooth

5. Ad Hoc Networking Piconet Scatternet
Share the same FHS using slotted TDD
Scatternet

6. Radio Parameters FHSS over 79 channels of width 1MHz Modulation: GFSK
k MHz, k = 0, …, 78
Modulation: GFSK
Transmit power
0 dBm ~ 20 dBm (provided power control) i.e.) 1 mW ~ 100 mW
Link range: 0.1 ~ 10m, (~100m, 20 dBm)
2.402
2.480
freq
time
slave
master
Bluetooth

7. Packet Transmission: FH/TDD Channel
access
code
packet
header
payload
72b
54b
0-2745b
625 ms t
master
slave
f(2k)
f(2k+1)
f(2k+2)
Slave may transmit in a slot
When master has polled the slave (ACL link)
When a master sends a broadcast packet in the preceding slot
When the slave alrready has a reservation for that slot (SCO link)
Bluetooth

8. Operational States master active slave parked slave standby Links
Power management
Active mode
Sniff mode: slave listens only at fixed interval
Hold mode: does not support ACL packets, but performs scanning, paging, inquiring, or attending another piconet
Park mode: gives up active member, however, stays synchronized to the channel
Links
ACL: asynchronous CL link for data comm.
Packet switched p-t-p, p-t-mp
SCO: synchnonous CO link for voice comm.
P-t-p symmetric
Support QoS

9. Protocol Stack RF Layer Baseband Layer Link Manager L2CAP
FH selection: (clock, address)  FH sequence
piconet creation
MAC procedures
Link Manager
Link setup (ACL/SCO)
Link control/configuration
Power mgmt/Authentication
L2CAP
HL protocol multiplexing
Segmentation/reassembly
QoS management
RFCOMM: Serial port emulation
TCS: telephony control

10. Bluetooth Profile

11. Bluetooth Architecture Update - Core
L2CAP layer
connection-oriented channels and connectionless broadcast to piconet
transport services for framed asynchronous and isochronous data
Upper baseband layer
Link Manager operates LM protocol
includes Device Manager and Resource Manager
transport services for unframed synchronous and isochronous data
Lower baseband layer
Link controller operating LC protocol
packet assembly/disassembly

12. Upper Baseband Layer Link Manager Device Manager
manages [logical] links
also manages (creates, modifies, destroys) logical channels and physical links
uses the LM protocol to communicate with peer link manager
interacts with device manager and resource controller
Device Manager
scanning, paging and inquiring operations
names, link keys, addresses, other local data
Baseband Resource Manager
contains the scheduler that allocates time to each operation and meets QoS commitments
contains a resource model to check and agree to QoS settings (traffic admittance control)

13. L2CAP - Functional Block
Channel Manager
manages the creation of L2CAP channels when requested by application creates/modifies/destroys baseband logical links (when required) to support different L2CAP channel types
negotiates QoS requirements with local link manager and remote channel manager
L2CAP Resource Manager
may check submitted traffic conforms to traffic flow specification agreed when channel created
manages potential limited buffering in Bluetooth Controller schedules (orders) PDU submission to baseband

14. Channels and Link

15. Physical Channel and Link
Characterized by timing and RF carrier hopping/occupancy
Identified additionally by channel access code
Physical link
Represents a point-to-point RF connection between two devices
May be active or parked

16. Logical Channel and Link
Basic transports for data traffic between connected devices
Different logical channels have behaviour suitable for data being transported
such as flow control, acknowledge/repeat mechanisms and scheduling requirements
Identified by LCID (logical channel identifier) field in packet header (p.k.a. AM_ADDR)
Logical Link
Some logical channels can support more than 1 type of traffic stream
ACO can carry LMP and L2CAP
logical link traffic may be interleaved subject to shared ARQn schemes
Logical links defined to distinguish LMP messages, L2CAP frames (and possibly others in the future)
Identified by LLID (logical link identifier) field in payload header (p.k.a. L_CH field)

17. Spec Update - Radio Evolution

18. High Priority Radio Improvements