1. November 2001
Project: IEEE P Working Group for Wireless Personal Area Networks (WPANs)
Submission Title: [IEEE Overview]
Date Submitted: [12 November, 2001]
Source: [Paul Gorday, Jose Gutierrez and PhilJamieson] Company: [Motorola/Eaton/Philips]
Address: [8000 W. Sunrise Blvd., M/S 2141, Plantation, FL 33322]
Voice:[(954) ], FAX: [(954) ],
Re: [IEEE Overview; Doc. IEEE /358r0]
Abstract: [This presentation provides overviews for the standard proposal.]
Purpose: []
Notice: This document has been prepared to assist the IEEE P It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein.
Release: The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

2. IEEE 802.15.4 Overview November 2001
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

3. 802.15.4 Applications Space Home Networking Automotive Networks
November 2001
Applications Space
Home Networking
Automotive Networks
Industrial Networks
Interactive Toys
Remote Metering
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

4. 802.15.4 Applications Topology
November 2001
Applications Topology
Cable replacement - Last meter connectivity
Virtual Wire
Wireless Hub
Stick-On Sensor
Mobility
Ease of installation
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

5. Some needs in the sensor networks
November 2001
Some needs in the sensor networks
Thousands of sensors in a small space  Wireless
but wireless implies Low Power!
and low power implies Limited Range.
Of course all of these is viable is a Low Cost transceiver is required
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

6. 802.15.4 General Characteristics
November 2001
Data rates of 250 kbps and 20 kbps.
Star or Peer-to-Peer operation.
Support for low latency devices.
CSMA-CA channel access.
Dynamic device addressing.
Fully handshaked protocol for transfer reliability.
Low power consumption.
16 channels in the 2.4GHz ISM band, 10 channels in the 915MHz ISM band and one channel in the European 868MHz band.
Extremely low duty-cycle (<0.1%)
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

7. 802.15.4 Architecture November 2001
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

8. IEEE 802.15.4 PHY Overview Paul Gorday November 2001
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

9. Operating Frequency Bands
November 2001
IEEE PHY Overview
Operating Frequency Bands
868MHz/
915MHz
PHY
Channel 0
Channels 1-10
2 MHz
868.3 MHz
902 MHz
928 MHz
2.4 GHz
PHY
Channels 11-26
5 MHz
2.4 GHz
GHz
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

10. Packet Structure (Both PHY’s)
November 2001
IEEE PHY Overview
Packet Structure (Both PHY’s)
PHY Packet Fields
Preamble (32 bits) – synchronization
Start of Packet Delimiter (8 bits) – specifies one of 3 packet types
PHY Header (8 bits) – Sync Burst flag, PSDU length
PSDU (0 to 127 bytes) – Data field
Start of
Packet
Delimiter
PHY
Header
PHY Service
Data Unit (PSDU)
Preamble
6 Bytes
0-127 Bytes
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

11. Modulation/Spreading
November 2001
IEEE PHY Overview
Modulation/Spreading
2.4 GHz PHY
250 kbps (4 bits/symbol, 62.5 kBaud)
Data modulation is 16-ary orthogonal modulation
16 symbols are ~orthogonal set of 32-chip PN codes
Chip modulation is MSK at 2.0 Mchips/s
868MHz/915MHz PHY
20 kbps (1 bit/symbol, 20 kBaud)
Data modulation is BPSK with differential encoding
Spreading code is a 15-chip m-sequence
Chip modulation is BPSK at 0.3 Mchips/s
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

12. IEEE 802.15.4 PHY Overview Common Parameters Transmit Power
November 2001
IEEE PHY Overview
Common Parameters
Transmit Power
Capable of at least 1 mW
Power reduction capability required if > 16 dBm
(reduce to < 4 dBm in single step)
Transmit Center Frequency Tolerance
 40 ppm
Receiver Sensitivity
-85 dBm (1% Packet Error Rate)
RSSI Measurements
Packet strength indication
Clear channel assessment
Dynamic channel selection
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

13. IEEE 802.15.4 PHY Overview PHY Primitives PHY Data Service
November 2001
IEEE PHY Overview
PHY Primitives
PHY Data Service
PD-DATA – exchange data packets between MAC and PHY
PHY Management Service
PLME-CCA – clear channel assessment
PLME-GET – retrieve PHY parameters
PLME-RX-ENABLE – enable/disable receiver
PLME-SET – set PHY parameters
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

14. IEEE 802.15.4 MAC/LLC Overview Phil Jamieson November 2001
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

15. Simple but flexible protocol
November 2001
Protocol Drivers
Extremely low cost
Ease of installation
Reliable data transfer
Short range operation
Reasonable battery life
Simple but flexible protocol
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

16. Example Network Network Node 4 coordinator Node 1 Node 5 Node 2 Node 6
November 2001
Example Network
Network
coordinator
Node 4
Node 1
Node 5
An example network topology in the area of home (living room) control. A set-top-box is acting as the master with a remote, TV, DVD, lamp and curtains enumerated on the network. This has no functionality since the slaves can only talk to the master. What the consumer actually wants is to be able to control the TV, DVD, lamp and curtains using the remote. In this case there needs to be some virtual peer-to-peer links between the remote and the other devices on the network. The mechanism of creating these links is known as pairing.
Node 2
Node 6
Node 3
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

17. Device Classes Full function device (FFD)
November 2001
Device Classes
Full function device (FFD)
Any topology
Network coordinator capable
Talks to any other device
Reduced function device (RFD)
Limited to star topology
Cannot become a network coordinator
Talks only to a network coordinator
Very simple implementation
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

18. Example Network FFD RFD FFD RFD RFD RFD FFD November 2001
An example network topology in the area of home (living room) control. A set-top-box is acting as the master with a remote, TV, DVD, lamp and curtains enumerated on the network. This has no functionality since the slaves can only talk to the master. What the consumer actually wants is to be able to control the TV, DVD, lamp and curtains using the remote. In this case there needs to be some virtual peer-to-peer links between the remote and the other devices on the network. The mechanism of creating these links is known as pairing.
RFD
RFD
FFD
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

19. Star Topology Full function device Communications flow
November 2001
Star Topology
Network
coordinator
Master/slave
Full function device
Communications flow
Reduced function device
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

20. Peer-Peer Topology Full function device Communications flow
November 2001
Peer-Peer Topology
Point to point
Cluster tree
Full function device
Communications flow
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

21. Combined Topology Full function device Communications flow
November 2001
Combined Topology
Clustered stars - for example,
cluster nodes exist between rooms
of a hotel and each room has a
star network for control.
Full function device
Communications flow
Reduced function device
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

22. Device Addressing All devices have IEEE addresses
November 2001
Device Addressing
All devices have IEEE addresses
Short addresses can be allocated
Addressing modes:
Network + device identifier (star)
Source/destination identifier (peer-peer)
Source/destination cluster tree + device identifier (cluster tree)
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

23. General Data Packet Structure
November 2001
General Data Packet Structure
Preamble sequence
Start of Packet Delimiter
PRE
SPD
LEN PC
ADDRESSING
DSN
Link Layer PDU
CRC
CRC-16
Data sequence number
Addresses according to specified mode
Flags specify addressing mode
Length for decoding simplicity
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

24. Optional Frame Structure
November 2001
Optional Frame Structure
GTS 3
GTS 2
Guaranteed
Time Slot
Reserved for nodes requiring guaranteed bandwidth [n = 0].
GTS 1
15ms * 2n
where 0  n  14
Network
beacon
Transmitted by network coordinator. Contains network information,
frame structure and notification of pending node messages.
Beacon
extension
period
Space reserved for beacon growth due to pending node messages
Contention
period
Access by any node using CSMA-CA
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

25. Traffic Types Periodic data Intermittent data
November 2001
Traffic Types
Periodic data
Application defined rate (e.g. sensors)
Intermittent data
Application/external stimulus defined rate (e.g. light switch)
Repetitive low latency data
Allocation of time slots (e.g. mouse)
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

26. Data Service Originator LLC Originator MAC Recipient MAC Recipient LLC
November 2001
Data Service
Originator
LLC
Originator
MAC
Recipient
MAC
Recipient
LLC
MD-DATA.request
Channel
access
DATA
MD-DATA.confirm
Packet
validation
HANDSHAKE
MD-H/S.indication
MD-DATA.indication
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

27. Management Service Access to the PIB GTS allocation Message pending
November 2001
Management Service
Access to the PIB
GTS allocation
Message pending
Node notification
Network scanning/start
Network synchronization/search
Paul Gorday, Jose A. Gutierrez and Phil Jamieson

28. Summary Star and peer-to-peer topologies Optional frame structure
November 2001
Summary
Star and peer-to-peer topologies
Optional frame structure
CSMA-CA channel access mechanism
Packet validation and message rejection
Handshake generation (for speed)
Optional guaranteed time slots
Guaranteed packet delivery
Frame fragmentation/reconstitution
Paul Gorday, Jose A. Gutierrez and Phil Jamieson