Body Area Networks

Katherine LiuOlivia Nordquist

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Agenda

Description

Motivation

Challenges

Applications

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What are they?

BAN, WBAN, BSN, BAWSN A network of sensors and actuators

residing within the limits of the body

Measure physiological data on the body Movement, position, levels Dispense medication, electric shocks,

etc.

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Motivation

The state of human health Heart and cardiovascular disease Diabetes Several cancers and chronic diseases

Allow for continuous monitoring of body

General sports and fitness monitoring

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Interaction with the Body

Invasive vs. non-invasive Most research is geared towards invasive

types

If invasive, nodes must be at least 60cm apart in body Based on government-regulated Specific

Absorption Rate (SAR) Too much exposure to electromagnetic fields

can harm the human body Maximum power density of 1.6 W/kg in U.S.

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http://www.imec.be/ScientificReport/SR2007/html/1384142.html

High-level overview of an invasive BAN

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Network

Follows IEEE 802.15 standard 802.15 specifies wireless personal area

network (WPAN) standards

New task group 802.15.6 as of December 2011 specifically for BAN Focusing on low-power, short-range

transfers in and around the body

Data transfer rates vary roughly from 10 Kbps to 10 Mbps

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Data rates vs. Power

http://www.cse.wustl.edu/~jain/cse574-08/ftp/ban/index.htmlEnergy and transfer rate comparisons amongst 802.15 groups

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Challenges

Energy

Noise

Embedded software

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Sources of Energy

Still a huge research topic Harvesting and storing energy

Issue with regular batteries? Large, needs replacing

Fuel cells possible alternative? More expensive, but only needs

refueling

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Comparing Energy Sources

Source Min Max

Kinetic Sources 40 microW 80 microW

Thermoelectric Sources 1 microW 30 microW

Source Min Max

Batteries 0.14 mW 150 mW

Fuel Cells 2.2 microW 430 microW

Energy Storage

Energy Harvesting

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Problem with Noise

The nodes send A LOT of data, much more than can be interpreted by the off-body infrastructure. The data does not take up all the broadband width so there do exist methods for dealing with the data but when a collision occurs, in BAN, the collision could mean life or death whereas Ethernet just means slower response times.

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http://www.imec.be/ScientificReport/SR2007/html/1384142.html

High-level overview of an invasive BAN

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Carrier Sense Multiple Access with Collision Detection (CSMA/CD)

Media Access Control

Method of arbitration

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A Simple Schematic

http://en.wikipedia.org/wiki/File:CSMACD-Algorithm.svg

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Why was that interesting

Method used for Ethernet, radio stations

Recent BAN research as of 2012

Life and death

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Embedded Software

Energy

Robust

Utilization of data inputs Memory footprints of interpreting device

Interpretation of biometrics

Cost: NP-Hard

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Healthcare Applications

http://www.cl.cam.ac.uk/techreports/UCAM-CL-TR-812.pdf

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Additional Applications

Military

Athletics

Seamless inter-BAN communication Intuitively bizarre Research new uses

http://news.discovery.com/human/life/advanced-crime-predicting-technologies-is-minority-report-here-infographic.htm

Questions???

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Sources

2011 Tenth International Symposium on Autonomous Decentralized Systems (ISADS), 519-24, 2011

2012 International Conference on Computing, Networking and Communications (ICNC), p 89-93, 2012

http://www.cl.cam.ac.uk/techreports/UCAM-CL-TR-812.pdf