1. Katherine Liu Olivia Nordquist
Body Area Networks
Katherine Liu
Olivia Nordquist

2. Agenda
Description
Motivation
Challenges
Applications

3. 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.

4. 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

5. 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.

6.
High-level overview of an invasive BAN

7. Network Follows IEEE 802.15 standard
specifies wireless personal area network (WPAN) standards
New task group as of December 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

8. Data rates vs. Power
Energy and transfer rate comparisons amongst groups

9. Challenges Energy Noise Embedded software
Noise: depending on the communication between nodes, multipath through the entire body vs cluster of nodes collecting the same data, the statistically model varies from Weibull/poisson process to uniform—creates wider variance for noise

10. 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

11. Comparing Energy Sources
Energy Storage
Source
Min
Max
Batteries
0.14 mW
150 mW
Fuel Cells
2.2 microW
430 microW
Energy Harvesting
Source
Min
Max
Kinetic Sources
40 microW
80 microW
Thermoelectric Sources
1 microW
30 microW

12. 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.
Csma-cd wiki, re-word, auction theory

13. High-level overview of an invasive BAN
Memory footprints, point out mucho data and the interpreting devices
High-level overview of an invasive BAN

14. Carrier Sense Multiple Access with Collision Detection (CSMA/CD)
Media Access Control
Method of arbitration
Draw picture here of beacon, reserve spaces v collisions, combination of the two styles proposed in paper

15. A Simple Schematic Go back a slide and draw the picture…..

16. Why was that interesting
Method used for Ethernet, radio stations
Recent BAN research as of 2012
Life and death
Ethernet refers to obsolete variants but there must exist backwards capabilities

17. Embedded Software Energy Robust Utilization of data inputs
Memory footprints of interpreting device
Interpretation of biometrics
Cost: NP-Hard
Kat discussed hardware energy components—software also needs to be efficient, auction theory: NP-hard, no pt m that can determine optimization

18. Healthcare Applications

19. Additional Applications
Military
Athletics
Seamless inter-BAN communication
Intuitively bizarre
Research new uses

20. Questions???

21. 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