`
`Advancing Technology
`for Humanity
`
`DECLARATION OF GERARD P. GRENIER
`
`I have never been convicted
`1, Gerard P. Grenier, am over twenty-one (21) years of age.
`of a felony, and I am fully competent to make this declaration.
`I declare the following to be true
`to the best of my knowledge, information and belief:
`
`I.
`
`I am Senior Director of Publishing Technologies of the Institute of Electrical and
`Electronics Engineers, Inc. (“IEEE”).
`
`2.
`
`IEEE is a neutral third party in this dispute.
`
`3. Neither I nor IEEE itself is being compensated for this declaration.
`
`4. Among my responsibilities as Senior Director of Publishing Technologies, I act as a
`custodian of certain records for IEEE.
`
`5.
`
`I make this declaration based on my personal knowledge and information contained
`in the business records of IEEE.
`
`6. As part of its ordinary course of business IEEE publishes and makes available
`technical articles and standards. These publications are made available for public
`download through the IEEE digital library, IEEE Xplore.
`
`7.
`
`It is the regular practice of IEEE to publish articles and other writings including
`article abstracts and make them available to the public through IEEE Xplore. IEEE
`maintains copies of publications in the ordinary course of its regularly conducted
`activities.
`
`8. The articles below, along with their abstracts, have been attached as Exhibits A — C to
`this declaration:
`
`A. G.S. Gupta, et al. “Design of a Low-cost Physiological Parameter
`
`
`
`Measurement and Monitoring Device” IEEE Instrumentation and
`
`
`
`Measurement Technology Conference Proceedings, May 1 ~ 3, 2007.
`
`
`L. Wang et al., “Multichannel Reflective PPG Earpiece Sensor With
`
`
`
`
`Passive Motion Cancellation” IEEE Transactions on Biomedical Circuits
`
`
`
`H. Han, Y. Lee, and J. Kim, “Development of a wearable health
`
`
`
`and Systems, Vol. 1, Issue 4, December 2007.
`
`
`
`monitoring device with motion artifact reduced algorithm (ICCAS 2007)”
`
`International Conference on Control, Automation and Systems, 2007,
`
`
`
`October 17 — 20, 2007.
`
`____________/
`
`445 Hoes Lane Piscataway, NJ 08854
`
`001
`
`APLl 106
`
`Apple v. Valencell
`IPR2017-003 l 8
`
`APL1106
`Apple v. Valencell
`IPR2017-00318
`
`001
`
`
`
`9.
`
`I obtained copies of Exhibits A — C through IEEE Xplore, where they are maintained
`in the ordinary course of IEEE’s business. Exhibits A — C are true and correct copies
`of the Exhibits as it existed on or about October 25, 2016.
`
`10. The article abstracts from IEEE Xplore shows the date of publication. IEEE Xplore
`populates this information using the metadata associated with the publication.
`
`11. GS. Gupta, et al. “Design of a Low-cost Physiological Parameter Measurement and
`Monitoring Device” was published as part of the IEEE Instrumentation and
`Measurement Technology Conference Proceedings. The IEEE Instrumentation and
`Measurement Technology Conference was held from May 1 — 3, 2007. Attendees of
`the conference were provided copies of the publication no later than the last day of
`the conference. The article is currently available for public download from the IEEE
`digital library, IEEE Xplore.
`
`12. L. Wang et al., “Multichannel Reflective PPG Earpiece Sensor With Passive Motion
`Cancellation” IEEE Transactions on Biomedical Circuits and Systems, Vol. 1, Issue
`4. IEEE Transactions on Biomedical Circuits and Systems, Vol. 1, Issue 4 was
`published in December 2007. Copies of this publication were made available no later
`than the last day of the stated publication month. The article is currently available for
`public download from the IEEE digital library, IEEE Xplore.
`
`13. H. Han, Y. Lee, and J. Kim, “Development of a wearable health monitoring device
`with motion artifact reduced algorithm (ICCAS 2007)” was published as part of the
`International Conference on Control, Automation and Systems, 2007. The
`International Conference on Control, Automation and Systems, 2007 was held from
`October 17 — 20, 2007.Attendees of the conference were provided copies of the
`publication no later than the last day of the conference. The article is currently
`available for public download from the IEEE digital library, IEEE Xplore.
`
`14. I hereby declare that all statements made herein of my own knowledge are true and
`that all statements made on information and belief are believed to be true, and further
`that these statements were made with the knowledge that willful false statements and
`the like are punishable by fine or imprisonment, or both, under 18 U.S.C. § 1001.
`
`I declare under penalty ofperjury that the foregoing statements are r1?correct.
`_,,..__.\
`Executed on: QQOJ. aOIé
`
`
`
`q.___
`,x
`
`002
`
`002
`
`
`
`
`
`
`
`
`
`EXHIBIT A
`
`EXHIBIT A
`
`003
`
`
`
`IEEE Xplore Document - Design of a Low-cost Physiological Parameter Measurement and Monitoring Device
`10/25/2016
`
` IEEE.org IEEE Xplore Digital Library
`
` IEEE-SA
`
` IEEE Spectrum
`
`More Sites
`
` Cart (0) Create Account
`
`
`|
`|
`|
`|
`|
`|
`
`
`
`Personal Sign In
`
`Institutional Sign In
`
`BROWSE
`
`MY SETTINGS
`
`GET HELP
`
`WHAT CAN I ACCESS?
`
`SUBSCRIBE
`
`
`
`Related Articles
`
` Back to Results | Next >
`
`Wearable
`medical
`devices for
`tele-home
`healthcare
`
`A WBAN-based
`System for
`Health
`Monitoring at
`Home
`
`A twenty-four
`hour tele-
`nursing
`system using
`a ri...
`
`
`
`View All Authors
`
`Browse Conferences > Instrumentation and Measureme...
`
`Design of a Low-cost Physiological Parameter
`Measurement and Monitoring Device
`
`184
`Full
`Text Views
`
`6P
`
`aper
`Citations
`
`Purchase or Sign In
`to View Full Text
`
`
`
`4
`Author(s)
`
` G. Sen Gupta ;
`
` S.C. Mukhopadhyay ;
`
` B.S. Devlin ;
`
` S. Demidenko
`
`Abstract
`
`Authors
`
`Figures
`
`References
`
`Citations
`
`Keywords
`
`Metrics
`
`Media
`
`Abstract:
`In this paper we present the design of a low-cost system that can be used to monitor physiological parameters, such as temperature and heart rate, of a
`human subject. The system consists of an electronic device which is worn on the wrist and finger, by an elderly or at-risk person. Using several
`sensors to measure different vital signs, the person is wirelessly monitored within his own home. An impact sensor has been used to detect falls. The
`device detects if a person is medically distressed and sends an alarm to a receiver unit that is connected to a computer. This sets off an alarm, allowing
`help to be provided to the patient. The device is battery powered for use indoors. The device can be easily adapted to monitor athletes and infants. The
`low cost of the device will help to lower the cost of home monitoring of patients recovering from illness. A prototype of the device has been fabricated
`and extensively tested with very good results.
`
`Published in: Instrumentation and Measurement Technology Conference Proceedings, 2007. IMTC 2007. IEEE
`
`Date of Conference: 1-3 May 2007
`
` INSPEC Accession Number: 9717999
`
`Date Added to IEEE Xplore: 25 June 2007
`
`DOI: 10.1109/IMTC.2007.378997
`
` ISBN Information:
`
`Print ISSN: 1091-5281
`
` Download PDF
`
`
`
` Download Citations
`
`View References
`
`
`
`Publisher: IEEE
`
`
`
` Contents
`
`
`
`I. Introduction
`Many elderly people dread the idea of being forced to live with their adult children, or in a rest home or
`in other sheltered living arrangement. They want to live independently and keep control of their own
`lives. Yet at the same time they know there is a high risk of injury or even death because of a fall or
`stroke. With the population aging in most developing countries, there will be more and more elderly
`people living alone in future. Such people need to be monitored continuously and provided with
`immediate medical help and attention when required.
`
`Read document
`
`Keywords
`
` Request Permissions
`
`IEEE Keywords
`Biomedical monitoring, Condition monitoring, Patient monitoring, Computerized monitoring, Costs,
`Heart rate measurement, Temperature sensors, Heart rate, Humans, Wrist
` Export
`http://ieeexplore.ieee.org/document/4258047/
`
`
`
`
`
`Full Text
`
`Abstract
`
`Authors
`
`Figures
`
`References
`
`Citations
`
`K
`
`d
`
`1/3
`
`004
`
`
`
`10/25/2016
`
`IEEE Xplore Document - Design of a Low-cost Physiological Parameter Measurement and Monitoring Device
`
`INSPEC: Controlled Indexing
`telemedicine, biomedical telemetry, patient monitoring, physiology
`
`INSPEC: Non-Controlled Indexing
`wireless transmission, low-cost physiological parameter measurement, monitoring device, electronic
`device, vital signs, impact sensor, patients monitoring
`
`Keywords
`
`Back to Top
`
`Author Keywords
`home monitoring, physiological parameters, sensors, wireless transmission
`
`Authors
`
`G. Sen Gupta
`School of Electrical and Electronic Engineering, Singapore Polytechnic, 500
`Dover Road, Singapore. Email: SenGupta@sp.edu.sg
`
`S.C. Mukhopadhyay
`Institute of Information Sciences and Technology, Massey University,
`Palmerston North, New Zealand. Email: s.c.mukhopadhyay@massey.ac.nz
`
`B.S. Devlin
`Institute of Information Sciences and Technology, Massey University,
`Palmerston North, New Zealand. Email: b.s.devlin@massey.ac.nz
`
`S. Demidenko
`Institute of Information Sciences and Technology, Massey University,
`Palmerston North, New Zealand. Email: s.demidenko@massey.ac.nz
`
` Share
`
` Alerts
`
`Related Articles
`» Wearable medical
`devices for tele-
`home healthcare
`K. Hung; Y.T. Zhang;
`B. T...
`
`» A WBAN-based
`System for Health
`Monitoring at
`Home
`Chris A. Otto; Emil
`Jovan...
`
`» A twenty-four hour
`tele-nursing
`system using a
`ri...
`Boo-Ho Yang;
`Sokwoo Rhe...
`
`» Long term remote
`behavioral
`monitoring of
`elderly...
`M. Ogawa; R.
`Suzuki; S. O...
`
`» A Passive and
`Portable System
`for Monitoring
`Hear...
`D.C. Mack; M.
`Alwan; B. T...
`
`» A Heart Pulse
`Monitoring System
`by Air Pressure
`a...
`Yutaka Hata; Yuya
`Kamozak...
`
`» Smart wearables
`for remote health
`monitoring, fro...
`A. Lymberis
`
`» Wireless ECG
`monitoring system
`Dina Simunic;
`Slaven Toma...
`
`» A Wireless
`Medical Monitoring
`Over a
`Heterogeneou...
`Mehmet R. Yuce;
`Peng Choo...
`
`» A MICS Band
`Wireless Body
`Sensor Network
`Mehmet R. Yuce;
`Steven W....
`
`http://ieeexplore.ieee.org/document/4258047/
`
`2/3
`
`005
`
`
`
`10/25/2016
`
`IEEE Xplore Document - Design of a Low-cost Physiological Parameter Measurement and Monitoring Device
`
`
`IEEE Account
`
` Purchase Details
`
` Profile Information
`
` Need Help?
`
`» Change Username/Password
`
`» Payment Options
`
`» Communications Preferences
`
`» Update Address
`
`» Order History
`» View Purchased Documents
`
`» Profession and Education
`» Technical Interests
`
`» US & Canada: +1 800 678 4333
`» Worldwide: +1 732 981 0060
`» Contact & Support
`
`
`Personal Sign In Create Account
`|
`
`
`
`About IEEE Xplore Contact Us
`|
`|
`
`Help
`
`
`|
`
`Terms of Use
`
`
`|
`
`Nondiscrimination Policy
`
`
`|
`
`Sitemap
`
`
`|
`
`Privacy & Opting Out of Cookies
`
`A not-for-profit organization, IEEE is the world's largest technical professional organization dedicated to advancing technology for the benefit of humanity.
`© Copyright 2016 IEEE - All rights reserved. Use of this web site signifies your agreement to the terms and conditions.
`
`http://ieeexplore.ieee.org/document/4258047/
`
`3/3
`
`006
`
`
`
`TMTC 2007 — Instrumentation and Measurement
`Technology Conference
`Warsaw, Poland 173 May 200
`
`Design of a Low-cost Physiological Parameter Measurement and Monitoring Device
`
`G. Sen Guptal, S.C. Mukhopadhyayl, B.S. Devlin2 and S. Demidenko2
`1School of Electrical and Electronic Engineering, Singapore Polytechnic, 500 Dover Road, Singapore
`2Institute of Information Sciences and Technology, Massey University, Palmerston North, New Zealand
`Email: s.c.mukhopadhyay@massey.ac.nz, SenGupta@sp.edu.sg, b.s.devlin@massey.ac.nz, s.demidenko@massey.ac.nz
`
`Abstract 7 In this paper we present the design of a low-cost system
`that can be used to monitor physiological parameters, such as
`temperature and heart rate, of a human subject. The system consists
`ofan electronic device which is worn on the wrist andfinger, by an
`elderly or at-rislc person. Using several sensors to measure different
`vital signs, the person is wirelessly monitored within his own home.
`An impact sensor has been used to detectfalls. The device detects if
`a person is medically distressed and sends an alarm to a receiver
`unit that is connected to a computer. This sets off an alarm, allowing
`help to be provided to the patient. The device is battery poweredfor
`use indoors. The device can be easily adapted to monitor athletes
`and infants. The low cost ofthe device will help to lower the cost of
`home monitoring ofpatients recovering =Jrom illness. A prototype of
`the device has been fabricated and extensively tested with very good
`results.
`
`— physiological
`Keywords
`transmission, home monitoring
`
`parameters,
`
`38115013“,
`
`wireless
`
`I.
`
`INTRODUCTION
`
`Many elderly people dread the idea of being forced to live
`with their adult children, or
`in a rest home or in other
`sheltered
`living
`arrangement.
`They want
`to
`live
`independently and keep control of their own lives. Yet at the
`same time they know there is a high risk of injury or even
`death because of a fall or stroke. With the population aging
`in most developing countries, there will be more and more
`elderly people living alone in future. Such people need to be
`monitored continuously and provided with immediate
`medical help and attention when required.
`The cost of hospitalization is ever increasing, so is the cost
`of rehabilitation after a major illness or surgery. Hospitals are
`looking at sending people back as soon as possible to recoup
`at home. During this recovery period several physiological
`parameters need to be
`continuously measured. Hence
`telemedicine and remote monitoring of patients at home are
`gaining added importance and urgency [1-3]. Today,
`the
`progress in science and technology offers miniaturization,
`speed, intelligence, sophistication and new materials at lower
`cost. In this new landscape, micro-technologies, information
`technologies and telecommunications are the key factors in
`inventing devices to assist mankind. Patients are being
`monitored using a network of wireless sensors [4]. A system
`to monitor the overall health of welfare facility residents, who
`need constant care, has been reported in [5]. This system [5]
`has been designed with wireless sensors, wireless repeaters
`and a host computer. The system consists of a piezoelectric
`
`sensor, a 2 axis accelerometer, a microcontroller and a low
`power
`transceiver.
`It
`records
`respiration activity and
`indicators of posture for 24 hours. These data are transmitted
`to the wireless repeater by the transceiver. The wireless
`repeaters, which are installed throughout the welfare facility,
`send data, including the repeater's ID, to the host computer.
`The ID is used to detect the resident's location in the welfare
`
`facility. The host computer stores the data, which can be used
`to analyze the resident's overall health condition. When the
`resident is in an emergency situation, such as falling or in an
`inactive state for more that
`the allotted time,
`the host
`computer automatically alerts the situation to the care staff by
`an alarm sound and also by mobile phone. However, all
`reported systems are relatively expensive.
`In the back drop of the importance of continuous
`monitoring of vital physiological parameters of a patient, our
`research was undertaken to design a
`low-cost
`smart
`monitoring device. It aims to provide peace-of-mind to users
`who have medical problems, but are not placed in a hospital
`for monitoring. Caregivers, who look after patients with
`mental or physical disabilities, can use this device when they
`are not able to visually supervise the patients.
`Currently there are monitoring products in the market that
`are aimed to provide emergency assistance to senior citizens,
`rehabilitation
`patients,
`and medically
`or
`physically
`challenged individuals, but these have limitations. St John’s
`and Medic Aler‘t’s LifelinkTM [6] allows the user to set off an
`alarm manually if they are under medical stress, which will
`then dial designated contact phone numbers. The fundamental
`problem with this system is that when medical emergencies
`happen to the user, they are often unconscious and unable to
`press an ‘emergency alert button”. There is no product on the
`market which does not require manual activation of the alarm
`and monitors a user’s vital signs smartly. This is the novel
`design goal of the work presented in this paper.
`The reported device consists of a wrist strap and a finger
`glove. This allows the sensors to be mounted around the wrist
`and finger. A battery and a microcontroller, with built-in RF
`transceiver, are mounted within the wrist strap as well. In
`Section II we present the complete system overview. All the
`sensors are explained in Section III. The hardware details are
`in Section IV and the algorithms in Section V. The prototype
`and test results are discussed in Section VI. The paper ends
`with a discussion on future developments
`
`1-4244-0589-0/07/$20.00 ©2007 IEEE
`
`007
`
`007
`
`
`
`ll. SYSTEM OVERVIEW
`
`B. HeartRale Sensor
`
`The system has been designed to take several inputs from
`a human subject to measure physiological parameters such as
`temperature and heart rate. Figure 1 shows the functional
`block diagram of the system hardware. The inputs from the
`sensors are processed and the results transmitted to a receiver
`unit, which is connected to a computer placed in the home,
`using Radio Frequency (RF) wireless
`technology. The
`receiver unit decodes and analyses the data. If it is inferred
`that the person is medically distressed, an alarm is generated.
`The design is modular which makes it rather easy and straight
`forward to add extra sensors for measuring and monitoring
`other parameters. The hardware blocks are explained in full
`details in a later section.
`
`A custom heart rate sensor was designed to read the
`patient”s beats per minute (bpm). The designed sensor is very
`small and inexpensive. The technique used to measure the
`heart rate is based on near-infrared (NTR) spectroscopy. NIR
`spectroscopy involves using light in the wavelength of 700-
`900nm to measure blood volume. At these wavelengths most
`tissues do not absorb light — other than hemoglobin (which is
`what we are interested in). This allowed for designing a non-
`invasive and low cost method of measuring the pulse. A
`silicon phototransistor and a GaAs infrared emitting diode
`were used in the sensor, moulded into a flat side-facing
`package. The amount of light
`that was detected by the
`phototransistor varied with the patients heart pulse, as the
`amount of absorbed IR light changed with the flow of blood,
`which is directly linked to the heart rate. This signal was then
`amplified,
`filtered, and sent
`to the microcontroller to be
`analyzed. The heart rate sensor was mounted in the finger
`glove as this position proved to give the best response.
`
`C. Impact Sensor
`
`An ADXL3ll accelerometer was used as an impact
`sensor. It provides a 2-axis response, measuring accelerations
`up to +/- 2g.
`It was fitted into the wrist
`strap. The
`accelerometer provides an analog voltage, the amplitude of
`which is directly proportional to acceleration. This signal was
`scaled down to bring it within the acceptable input range of
`the micro-controller, and then analyzed. Software algorithms
`were used to detect sharp impacts, while allowing slower
`movements, such as walking, to be ignored. The purpose of
`this sensor was to detect sudden impacts that could indicate
`the patient had fallen over.
`
`TV. HARDWARE DESIGN
`
`The hardware was built in three separate blocks. A sensor
`card was designed to house
`the
`temperature
`sensor,
`accelerometer and the connections for the NIR emitter and
`
`the
`detector. A separate analog card was designed for all
`analog processing circuitry needed for the sensors, primarily
`for processing the heart rate signal. The temperature and
`acceleration output was fed directly to the micro-controller.
`The micro-controller was mounted on a separate card which
`also had the antenna connection. The cards were connected
`
`by ribbon cables within the wrist strap. Figure 2 shows the
`circuit schematics of the sensor units and Figure 3 shows the
`analog processing circuit for measuring heart beat rate.
`
`A. Lock-In Amplification for heart rate measurement
`
`The micro-controller modulates
`
`the infra-red emitter
`
`signal at l KHZ through a npn transistor (Figure 2). This is
`then mixed with the signal obtained from the IR sensors
`(back scattered light). This technique, known as Lock-In
`Amplification
`[9],
`involves phase
`sensitive
`detection.
`
`008
`
`Impact Sensor
`(Accelerometer)
`
`0mm
`2 4on RF
`
`j
`+5“ Mixedemgnal
`Temperature
`r
`'
`micmecummiler
`microcontroller
`
`
`Sensor
`.
`i
`With RF
`Wm RF
`1—.
`PC
`
`‘4
`Circuitry +5 Transmitter“
`Receiver
`R5232
`\ Anaiog Signals
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`Heait Rate
`Sensor
`Circuin
`
`Fig. 1. Functional block diagram ofthe system hardware
`
`III. SENSORS AND INTERFACE
`
`The system consists of three sensors- a temperature sensor,
`heart rate sensor, and an impact sensor. All
`the sensor
`circuitries used in the design generate analog voltages which
`are fed to the ADC (Analog-to-Digital) inputs of the micro-
`controller. The ADC inputs
`are
`time-multiplexed and
`sampled at different rates. The description of individual
`sensors follows.
`
`A. Temperature Sensor
`
`The temperature measurement is done using a LM35 [7]
`precision integrated-circuit temperature sensor. It provides an
`accuracy of +/— 025°C within the desired temperature
`measurement range of 20-4OOC. It has a very low current
`drain of 60 uA. This sensor is mounted within the wrist strap,
`positioned in such a way that it is in contact with the skin,
`allowing it to measure the extemal temperature of the skin.
`From the skin temperature, the body temperature is estimated.
`Because an exact measurement of body temperature is not
`required, this method is suitable. Rather, relative changes are
`monitored within set thresholds, which set off the alarm. This
`allows the device to detect changes in body temperature that
`could indicate the patient is undergoing any of the following
`conditions:
`trauma,
`injury, heart
`attack,
`stroke, heat
`exhaustion, and burns [8]. The temperature sensor is sampled
`once every 3 seconds.
`
`008
`
`
`
`
`Ancient-melee
`
`
`ADXLSH
`;
`
`
`
`
`i,
`
`
`
`RJE
`l 00K
`i_.w.. _ ..‘3
`
`
`
`ii
`
`l
`2m
`w‘
`SW_FB
`T,,¢,j_)
`Filamjl at:
`
`Eargug‘iajump
`
`_
`
`__
`_
`..
`
`
`
`:
`SW_PB
`
`,
`T, j
`—
`:lamj '2ng
`
`51:6HUK
`
`
`
`.1 KHZ
`Square
`
`
`
`um:
`ER signal tmnsmééaer
`and receiver
`
`
`
`
`
`
` I). 7M
`
`
`
`“J 1:3.
`“NR?
`251k ”
`
`.;RS
`9320
`
`v3:
`
`
`
`
`
`i 77D}
`
`
`1 a‘
`Photo Sex,
`
`2,. Q1
`.‘ QUIT”
`
`..
`
`
`Limmc'ifll in main; gym;
`
`(:7
`
`
`
`Fig. 2. Sensor Units
`
`
`1
`:
`
`332A
`mam];
`
`matey Mae {demodelaring}
`"mm
`
`'—
`{i we;
`
`*l
`
`V23
`
`“i
`
`7
`
`
` Signal 35m:
`
`
`
`[12C
`TDZ'EMCD
`
`
`
`
`
`
` —_— Sigma! tauefiefixl Gain;
`
`
`AG couple and amaflfiemim (x135 gain}
`
`Fig. 3. Signal conditioning for Heait Rate Monitoring
`
`The signal of interest (1-2 Hz) is moved into a much higher
`frequency band together with the noise that is picked up by
`the sensors. Demodulation is performed by an analog switch,
`which demodulates at the same frequency and in phase with
`the l KHZ modulating signal. The resulting signal is then
`passed through a low-pass filter with a cut off frequency of
`6Hz. This allows the signal of interest to pass through, while
`filtering out all noise that originated from the sensor. This is
`illustrated in figure 4.
`
`B. Controller Cand
`
`The controller used in the wrist strap unit (and also in the
`receiver unit) is a Nordic nREF24El. This takes inputs from
`
`009
`
`
`
`
`
`
`
`gar"Jinanwe
`:;
`5 Eflmn‘flnl
`!
`a ripli'eiue
`am
`'
`‘-
`award14$:in
`E; Ammmm
`i:
`
`new puss fiéier
`
`
`
`Fig. 4. Lock-In Amplification for heart rate measurement
`
`the sensor circuits in the form of analog voltages. Each sensor
`has a dedicated ADC channel which is multiplexed by the
`microcontroller. Each sensor”s signal
`is sampled at a pre-
`defined rate,
`through interrupt-driven algorithms. This
`microcontroller was chosen because of its small footprint
`(6mm X 6mm),
`low power consumption,
`and built-in
`
`009
`
`
`
`transceiver. The microcontroller is responsible for producing
`the carrier signal that modulates the IR emitting diode, which
`is used in demodulation too. It is powered by a 9V battery,
`which is regulated down to 5V. The controller card contains
`the microcontroller, crystal oscillator, RF antenna connection,
`and header pins which connect analog and digital pcrts to the
`other components ofthe unit
`
`0. Receiver Um:
`
`sent by the nREF24El using a
`is
`The data packet
`technology termed ShockBurstTM. This allows data to be
`clocked into a FIFO buffer at a low data rate, and then
`transmitted all at once at a very high rate. This lowers power
`consumption by minimizing the amount of receiving and
`transmitting time. Data is transmitted by this method at
`1Mbps. This also reduces the risk of a data collisicn with
`other wrist units, or devices operating in the same band.
`
`V. SOl-TWAiib, AND ALGORllHMS
`
`The hardware of the receiver unit is housed in a plastic
`box and consists of a nREF24El microcontroller, antenna, a
`5V AC adaptor and serial interface port. The receiving unit '5
`connected, via a RS232 serial port, to a personal computer
`@C) and is constantly receiving information about
`tl'e
`patient’s medical
`status. A program, running on the PC,
`receives the packetized information from the serial port,
`decodes the packet and then displays this informaticn on tle
`PC monitor. The program offers several optims to set
`thresholds of the allowable range of heart
`rate,
`skin
`temperature and impact sensor. Whm the readings from tl'e
`patient move outside ofthe set range, an alarm is raised. Tl'e
`software can depict
`the change in data over
`time in a
`graphical plot. One receiver unit can be interfaced with
`multiple wrist units. In the software, one can tab through tl'e
`information received fi‘om each wrist unit.
`
`
`
`D. Communication
`
`Communication between the wrist units and the receiver
`
`unit is wireless, powered by the nREF24El, and transmitted
`in the unlicensed 2.4GHz fi‘equency band. Information is
`gathered every 3 seconds fi‘om the sensors and then encoded
`into a packet. Each packet
`is 6 bytes long, composed as
`shown in figure 5.
`
`Start of File
`
`4—" Sit balanced (19101030)
`
`the
`on
`implemented
`algorithms were
`Several
`from the
`take inputs
`microcontroller. These algorithms
`sensors and process them into meaningful information.
`
`A. Heart Rate Algoriflm
`
`The heart rate signal is an oscillating signal of] to 2H2. This
`is sampled by the microcontroller at 50Hz, and then averaged
`over 5 samples, which gives the algorithm an effective data
`input rate of 10 samples per second. This is stored in a buffer
`which is 32 bytes long. Once this buffer is fill, the algorithm
`scans though each value in the buffer to compute the period
`of the signal (see figure 6). Since the signal is not sinusoidal,
`rather has distinct peaks corresponding to the contractions in
`the heart, the period is measured by marking transitions over
`the 25% mark. This is the most reliable part of the received
`signal. Since the sample time is know (0.13), the number of
`samples between these ‘transition points” is used to calculate
`the period and hence the fi‘equency. The frequency is then
`multiplied by 60 to compute the heart rate (in bpm, beats per
`minute) of the patient
`Is. not :tlL'IFISCIF-
`
`Peron
`
`Fly/W .
`'ur-‘ilhi
`1!} S-amsmdmslm
`
`
`
`Fig. 6. Heartrate measurement algorithm
`
`5 Bytes tong
`
`Biihalancafl [10101013]
`
`Skin Temperalme
`
`Impact Information
`
`End of File
`
`Fig. 5. Datapacket composition
`
`5’. Imp-act Algorithm
`
`is in beats per
`The heart rate included in the packet
`minutes (bpm) which is calculated using the Heart Rate
`Algorithm explained in Section V. The temperature data is
`the result ofthe ADC conversion, done once every 3 seconds,
`and is decoded into degrees Celsius at the receiver unit. The
`impact informaticn is the maximum output voltage of the
`accelerometer measured in the past 3 seconds. This is also the
`
`digital value obtained from the ADC conversion.
`
`is a DC
`The signal received from the accelerometer
`voltage,
`the amplitude of which is directly related to the
`acceleraticn (62m‘lfi‘g). This input is sampled at IOHZ, and
`stored in a buffer which is 10 bytes long. Every second, this
`buffer is scanned, and the maximum amplitude is recorded.
`At
`the receiver unit,
`this data is compared to recorded
`representative values for walking and jogging. This ensures
`that an alarm is set off only for very sharp, heavy impacts.
`
`010
`
`010
`
`
`
`The reliability of impact detection was very good and the
`walking could easily be differentiated from a fall.
`
`with thumb on carotid artery). Figure 9 shows a segment of a
`received heart rate signal.
`
`VI. PROTOTYPE AND EXPERIMENTAL RESULTS
`
`The Nordic micro-controller development board was used
`to build and test the prototype design. The analog processing
`circuitry and the sensors were assembled on PCBs which
`were placed within the wrist strap. Figure 7 shows the
`prototype hardware. The prototype was powered off a 9V
`battery. The RF transmission has been tested to operate
`successfully at 10 meters range through obstacles such as
`concrete walls. The receiver unit. without the casing, can be
`seen in figure 8.
`
`
`
`Fig. 8. Prototype receiver connected to a PC
`
`A. Heart Rate Sensor Test Results
`
`A new heart rate is calculated every 3.2 seconds. The
`output of the sensor is a 200-400 mV p-p signal, riding a DC
`signal of SOOmV. 011 human tests it is able to measure within
`21:2 bpm of a rested patient (continued by measuring pulse
`
`011
`
`Fig. 9. Segment of a heart rate signal
`
`B. Impact Sensor Test results
`
`The output of the accelerometer was tested with walking
`and simulated falling. The results showed the difference was
`simple to detect and proved the accuracy of the algorithm.
`Figure l0 shows the impact sensor output.
`
`
`
`Fig.
`
`IO. Impact sensor output for walking and a fall
`
`VILDISCUSSIONS AND FUTURE DEVELPOMENTS
`
`In this paper we have presented the research, of applied
`nature, done to monitor physiological parameters such as skin
`temperature, heart rate and body impact. A prototype was
`successfully developed and tested to establish the proof of
`concept. The algorithms were tested and found to be accurate
`and reliable. The novel aspect ofthe design is its low cost and
`detection of medical distress which does not necessitate
`
`pressing any panic button. This is an enormous improvement
`over existing commercial products.
`An important aspect of the design was miniaturization, so
`that the system was as non-intrusive as possible to the wearer.
`This was achieved by the use of surface-mounted devices on
`the PC83 designed. Low power operational amplifiers were
`used to minimize battery consumption. The price of the unit
`currently is $70. The major costs come from the use of
`precision components, accelerometer and temperature sensor.
`With some modification, the system can be made available
`commercially. Future improvements will focus on the use of
`
`011
`
`
`
`REFERENCES
`
`Ohta S, Nakamoto H, Shinagawa Y, Tanikawa T., “A health
`monitoring system for
`elderly people
`living alone”,
`Journal of
`Telemedicine and Telecare, Vol 8, No. 3, June 2002, pp. 151-156
`C.,
`Dittrnar
`A,
`Axisa
`F,
`Delhomme
`G,
`Gehin
`“New concepts and technologies in home care and ambulatory
`monitoring”, Studies in health technology and informatics, 2004, pp 9-
`35.
`Fazlur Rahman, Arun Kumar, G Nagendra, and Gourab Sen Gupta.
`"Network Approach for Physiological Parameter Measurement”, IEEE
`Transactions on Instrumentation and Measurement, February 2005, Vol
`54, No.1, pp 337-345
`Jovanov E, Raskovic D, Price J, Chapman J, Moore A, Krishnamurthy
`A., “Patient Monitoring Using Personal Area Networks of Wireless
`Intelligent Sensors”, Biomedical Sciences Instrumentation, 2001, pp
`373-378
`
`Button,
`
`Maki H, Yonczawa Y, Ogawa H, Sato H, Hahn AW, Caldwell W.,
`“A welfare facility resident care support system”, Biomedical Sciences
`Instrumentation, 2004, pp 480-483.
`LifeLink
`Panic
`http:/fwww.bgehome.com/hs_protection.html#lifelink
`National Semiconductor, LM35 — Precision Centigrade Temperature
`Sensor, http://www.national.com/pfi'LM/LM35 .html
`Y.C.Sydney, A-Z Health Guide from WebMD: Medical tests, Body
`Temperature,
`http:/fwwwwebmd.com/hw/healthgguideiatoz/hw198785asp
`Eastern Michigan University, Lock-In Amplification
`http:/fwww.physics.emich.edu/molab/lock-in/indexhtml
`WD .Peterson., D.A.Skramsted., D.E.Glumac, Piezo Film Pulse
`Sensor,http:/fwww.phoenix.tc-ieee.orgf0047PiezoiFilm7Bloodi
`Flowisensor/PhoenixiPiezoPulse.htrn
`
`overview,
`
`flexible PCBs to replace the stiff cards, so that it could be
`moulded around the wrist unit, making it more comfortable
`for the wearer.
`
`The design of the IR sensors could be improved to
`decrease its susceptibility to noise, to a point where it could
`be moved onto the wrist unit. This would provide a much
`more comfortable and less intrusive unit, getting rid of the
`finger glove.
`The addition of a blood-oxygen sensor would allow the
`system to detect medical