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Biosensor Networks

Principal Investigators: Frank Merat, Wen H. Ko, Darrin Young

Case Western Reserve University

NASA SpaceCommunications

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Biosensor Networks

Project Overview

The goal of this project is to develop a test platform for biomedical monitoring using COTS components and state-of-the-art communications concepts.

Body drawing from Fundamentals of Bioelectrical Impedance Analysis, Rudolph J. Liedtke, RJL Systems, February 1998.

RF SourceSpectrum Analyzer

Biomonitoring NetworkComputer Medical

Data Logger/Analysis Station

Conventional RF Link (BlueTooth?)

IntraBody Wireless Network

IntraBody/Extrabody Wireless Network

Router

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Biosensor Networks

Relevance

This technology has applications for continuous health monitoring of humans in space and for long duration space experiments involving humans and/or animals.Any wireless solution should interface with existing and future proximity networks.

“A Lightweight Ambulatory Physiological Monitoring System,” NASA Tech Briefs, January 2001.

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Biosensor Networks

Impact

The major impact of this technology is upon manned missions, e.g., space station and shuttle missions .

Removal of wires and other encumbrances would improve astronaut freedom of movement and increase the system reliability.

Wireless Biosensor Network

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Biosensor Networks

Feasibility Experiment

Body drawing from Fundamentals of Bioelectrical Impedance Analysis, Rudolph J. Liedtke, RJL Systems, February 1998.

RF SourceSpectrum Analyzer

RF Phantom

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Biosensor Networks

Characterize human body as rf communications channel

Received Power Through the Body (underside of forearm with 30 cm separation). Antenna dimensions: L =39 mm, W = 42

mm, and h = 0.062” on FR-4 substrate.

Received Power at 50 cm separation.Transmitter antenna: L = 54 mm, W = 48 mm, h = 0.062”; receiver antenna L = 26

mm, W = 38 mm, h = 0.062”, both on FR-4 substrate.

Geometry of Basic Rectangular Patch Antenna

Received Power at 1 m separation. Antenna dimensions are L = 41 mm, W = 38 mm, and h = 0.062” on FR-4 substrate.

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Biosensor Networks

Prototype sensor node

Typical rectangular center fed patch antenna used for testing.

Bare PC board for prototype

Prototype sensor node with integrated antenna and D-socket for programming

“early” power for prototype

Antenna board for prototype

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Biosensor Networks

Propagation modeling

Simulation of Transmission Line Model for 0.6 Meters Antenna Separation

Transmission Line Model of Antenna/Human Circuit using experimentally measured antenna parameters and

published values for the electrical parameters of the human body

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Biosensor Networks

Papers and Awards

[1] M. Dummeruth. Wireless Wearable Health Monitoring System. M.S. Thesis, Case Western Reserve University, August 2002. (Advisor: F. Merat).