The network uses IEEE 802.15.4 compatible
radios operating in the 2.4GHz ISM radio
Distance Up to 250m line-of-sight between
Topologies: Mesh, Star, Combined Star &
Power Options: Line Powered or Battery
Physical Layer (IEEE 802.15.4)
Data Link Layer
Network Layer and Transport Layer
Maximum data rate (250 kbps)
Operating Frequency (2400 – 2483 MHz)
Defines radio characteristics, such as signaling
method, signal strength and device sensitivity.
TDMA technology to provide collision free
To provide secure and reliable end to end
communication for network devices.
To support mesh communication
There are two routing protocol
1) Graph Routing
2) Source Routing
It is command oriented and hundreds of
command have been already defined in it.
It is also possible for users to define their
WirelessHART devices will be widely installed
in thousands of factories. And it is valuable to
know the locations of workers and assets
because of the hazardous conditions in
industrial environment, for example, a
chemical leak, a tornado.
However, there is no location awareness
support in WirelessHART
All field devices are attached to fixed
We need to locate the handheld device
The handheld device can sense the signal
strength from neighboring field devices
Also, field devices can also sense the signal
strength of the handheld device
However, two devices can not communicate
with each other for security issues
Then, how to compute the location?
Both field devices and the handheld device
send neighbor health reports to the network
manager periodically, which contain receive
signal strength of their neighbors.
Thus, the network manager gets pairs of
receive signal strength .e.g. field device 1
reports RSS of the handheld device is 50dbm and the handheld device report RSS of
field device 1 is -51 dbm.
Then, the network manager can choose most
trustable pairs of receive signal strength by
comparison and compute the location of the
handheld device by trilateration
Three kinds of distance indication
◦ RSSI (Received Signal Strength Indicator)
It makes use of signal strength decay models to estimate
◦ TDOA(Time Difference of Arrival)
It makes use of signal (usually sound) propagation speed
◦ AOA(Angle of Arrival)
It determines the direction with antenna array
Our solution is based on RSSI because we do
not want to add extra devices to hardware
Demo board will be Microcontroller based
Transceiver will be IEEE 802.15.4 2.4 GHZ RF
Handheld device will be either GPS or GSM
In many large factories (e.g.
refineries, chemical plants) to track the
location of workers.
There is no location awareness application
 HART Communication. http://www.hartcomm2.org
 Saikat Guha, Rohan Narayan Murty and Emin Gun Sirer. Sextant:
A Unified Framework for Node and Event Localization in Sensor
Networks. In Proc. of MobiHoc 2005, May 2005.
 Shu Chen, Yingying Chen, Wade Trappe, "Exploiting
Properties for Wireless Localization," the Thirteenth Annual
International Conference on Mobile Computing and Networking
(MobiCom 2007), Montreal, Canada, September 2007.
 J. Song, S. Han, A. K. Mok, D. Chen, M. Lucas, M. Nixon, and W.
Pratt, WirelessHART: Applying Wireless Technology in Real-Time
Industrial Process Control. Real-Time Technology and
Applications Symposium, 2008.
 BAHL, P., AND PADMANABHAN, V. RADAR: An In- Building
RF-based User Location and Tracking System. In Proc. IEEE
INFOCOM (Tel-Aviv, Israel, Mar. 2000].