Wireless Body Area Wireless Body Area NetworkNetwork

Presented By :Soroush Gorji Makhsous 810187057

Class Presentation for Custom Implementation of DSP Systems Course

Spring 2010

This presentation is mostly based on ISSCC2010 conference paper: A 110 uW 10Mb/s eTextiles Transceiver for Body Area Networks with Remote Battery PowerPatrick P. Mercier, Anantha P. Chandrakasan ,Massachusetts Institute of Technology

University of Tehran

School of Electrical and Computer Engineering

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Outline

•Introduction•Wireless Body Area Network•Sensor Devices •WBAN Application Areas•Body Sensor Network•Technical Requirements•Electronics Textiles•Conclusion

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Introduction• An aging population and sedentary lifestyle are fueling the

prevalence of chronic diseases such as cardiovascular diseases, hypertension, and diabetes. According to the WHO, cardiovascular disease causes 30 percent of all deaths in the world. Diabetes currently affects 180 million people worldwide and is expected to affect around 360 million by 2030. More than 2.3 billion people will be overweight by 2015. A rapid rise in debilitating neuro-degenerative diseases such as Parkinson’s and Alzheimer’s is threatening millions more.

• The advent of miniaturized sensors and actuators for monitoring, diagnostic, and therapeutic functions, and advances in wireless technology have opened up new frontiers in the race to conquer healthcare challenges. Ultra-low-power wireless connectivity among devices placed in, on, and around the human body is seen as a key technology enabling unprecedented portability for monitoring physiological signs in the hospital, at home, and on the move.

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Introduction• Body area networking (BAN) technology has the potential to

revolutionize healthcare delivery in ambulances, emergency rooms, operation theaters, postoperative recovery rooms, clinics, and homes. The benefits of unobtrusive, and continuous monitoring/treatment include long-term trend analysis, detection of transient abnormalities, prompt alerting of a caregiver to intervene in case of an emergency, regulation of treatment regimes, reduction of errors, reduction of hospital stays, extending independent living for seniors, and improved patient comfort. BAN offers a paradigm shift from managing illness to proactively managing wellness by focusing on prevention and early detection/treatment of diseases.

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Wireless Body Area Network• A wireless body area network (WBAN) connects independent

nodes (e.g., sensors and actuators) that are situated in the clothes, on the body or under the skin of a person. The network typically extends over the whole human body and the nodes are connected through a wireless communication channel.

• According to the implementation, these nodes are placed in a star or multi hop topology . A WBAN offers many promising, new applications in home/health care, medicine, sports, multimedia, and many other areas, all of which make advantage of the unconstrained freedom of movement a WBAN offers.A Wireless Body Area Network (WBAN) consists of several small devices close to, attached to or implanted into the human body. These devices communicate by means of a wireless network. Interaction with the user or other persons is generally handled by a central device, e.g. a PDA

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Wireless Body Area Network• The WBAN system is divided into three levels:

1. The lowest level consists a set of intelligent sensors or nodes. These are the reduced function devise. These can only communicate with there parent device and cannot act as parent.

2. The second level is the personal server (Internet enabled PDA, cell-phone, or home computer). These are full function devices. And they can communicate with there children as well as with the external network.

3. The third level encompasses a network of remote server which is the remote application to which data or information is transferred.

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Wireless Body Area Network

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Sensor level Personal Server LevelMedical Service Level

E. Jovanov, et al., “A wireless body area network of intelligent motion sensors for computer assisted physical rehabilitation,” Journal of NeuroEngineering and Rehabilitation, 2005, 2:6

Sensor Devices• Sensors fall into three categories:

1. Physiological sensors : measure ambulatory blood pressure, continuous glucose monitoring, core body temperature, blood oxygen, and signals related to respiratory inductive plethysmography, electrocardiography (ECG), electroencephalography (EEG), and electromyography (EMG).

2. Biokinetic sensors : measure acceleration and angular rate of rotation derived from human movement.

3. Ambient sensors : measure environmental phenomena, such as humidity, light, sound pressure level, and temperature.

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[4]

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[4]

Sensor Devices

WBAN Application Areas

•Body senor network•Fitness monitoring•Wearable audio•Mobile device centric•Gaming & Entertainment•Consumer Electronics Applications :

media players, and headsets

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WBAN Application Areas

[2]

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•Medical application▫Wearable Monitoring Systems▫Pulse Oximeter▫Electrocardiograph (EKG)▫Electroencephalography (EEG)▫Electromyography (EMG)

Slide 12

Body Sensor Network

Body Sensor Network

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[4]

Slide 14

Technical Requirements

•Architecture •Density•Data rate•Latency•Mobility

Slide 15

Technical Requirements

•There is no specific standard for BANs▫Current standards come close for specific use

cases, not broad enough▫Issues: power consumption, discovery, QoS▫Support for very low power devices, sensors

•Target less than 10% power consumption for communications compared to total device

•Have single standard with broad range of supported data rate - scalability

Technical requirements of selected BAN applications [2]

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Data rates and power requirements for WBAN according to [6].

Technical Requirements

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Technical Requirements

Characteristics of candidate technologies for WBAN [4]

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Technical Requirements

Merits and demerits of candidate technologies for BAN [4]

Electronics Textiles (eTextiles)

[1]

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Implemented eTextiles system [1]

Electronics Textiles (eTextiles)

• An emerging technique for conveying information around the human body uses electronics textiles (eTextiles) as a communication medium.

• The medium consists of two electrically separate grids of conductive yarn. Sensor nodes physically connect to the shared medium using metallic button-snaps, and communicate via an eTextiles transceiver chip.

• Using a pair of physical low-impedance connections has the distinct advantage over wireless and/or BCC systems to be able to: ▫ 1) signal differentially, permitting energy-efficient amplitude-

modulation schemes that tolerate coupled interference, and ▫ 2) power sensor nodes remotely from a local basestation (BS) at

extremely high efficiency, minimizing the energy storage requirements on each node.

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[1]

eTextiles transceiver block diagram

[2]

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eTextiles transceiver block diagram used for sensor nodes. The BS uses the same chip, but replaces the super capacitor with a battery [1].

Die Photograph & Chip Summary [1]

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Conclusion• WBAN opens up a whole new field of sensor networking

and intelligent technology. It is a very practical way to track user activities for different purposes. It has a wide range of implementations in Medical rehabilitation, digital IDs, military and ultimately to personal entertainment systems. There are some design and social issues which are currently posing some limitation on commercial level implementation of WBAN.

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References1. ISSCC 2010 / DIRECTIONS IN HEALTH, ENERGY & RF / A 110 W

10Mb/s eTextiles Transceiver for Body Area Networks with Remote Battery Power, Patrick P. Mercier, Anantha P. Chandrakasan ,Massachusetts Institute of Technology, Cambridge, MA

2. Enabling Technologies for Wireless Body Area Networks: A Survey and Outlook,Huasong Cao and Victor Leung, University of British Columbia Cupid Chow and Henry Chan, The Hong Kong Polytechnic University

3. A 1.12 pJ/b Inductive Transceiver With a Fault-Tolerant Network Switch for Multi-Layer Wearable Body Area Network Applications, Jerald Yoo, Student Member, IEEE, Seulki Lee, Student Member, IEEE, and Hoi-Jun Yoo, Fellow, IEEE JOURNAL OF SOLID-STATE CIRCUITS, VOL. 44, NO. 11, NOVEMBER 2009

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References4. Body Area Sensor Networks: Challenges and Opportunities ,Mark A.

Hanson, Harry C. Powell Jr., Adam T. Barth, Kyle Ringgenberg, Benton H. Calhoun, James H. Aylor, and John Lach, University of Virginia , IEEE Computer Society 2009

5. Data Security And Privacy In Wireless Body Area Networks, Ming Li And Wenjing Lou, Worcester Polytechnic Institute Kui Ren, Illinois Institute Of Technology, IEEE Wireless Communications • February 2010

6. S. Drude, “Requirements and application scenarios for body area networks,”in Proc. Mobile Wireless Commun. Summit, 2007, 16th IST, Jul.1–5, pp. 1–5.

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Thank for your attention

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