ecc08 malta

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Development of wireless Body Area Network based on J2ME for M-Health applications

WSEAS European Computing Conference (ECC’08)

Development of wireless Body Area Network based on J2ME for M-Health

applications

Departamento de Tecnología Electrónica. University of MálagaETSI de Telecomunicación, Campus de Teatinos, 29071 – Málaga- SpainE-mail: [email protected], [email protected]

M.J. Morón*, J.R. Luque*, E.J. Cuberos*, A.A. Botella*,

E. Gallardo*, E. Casilari*, A. Díaz Estrella*, J.A. Gázquez**

*UNIVERSITY OF MÁLAGA, **UNIVERSITY OF ALMERÍA, SPAIN

Malta, September 11th, 2008

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Index

1. Introduction: Brief state of the art2. Goals3. System description4. Testbed Results and present state of

the prototype

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INTRODUCTION

Continuous MonitoringCertain illnesses/sectors of population

NEED of Wireless Telemedicine SOLUTION: M-health

Quality of life1)

Mobility2)

Traditional wired sensors

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Experiences on M-health: Medical Wireless BAN

Mobile Health (M-Health): integration of technologies of mobile computing and medical sensors with wireless communications in a system of sanitary assistanceStrong international efforts and research on this issue…CodeBlue, a wireless architecture designed in Harvard University for emergency medical care. The project integrates low-power, wireless vital sign sensors, PDAs, and PC-class systemsAMON [Dec.2004]: A wearable multi-parameter sensor. Continuous collection of multiple vital signs in wrist-worn enclosure with cellular communications

USE of short-range communication StandardsLow-power standards (Bluetooth, Zigbee,) in telemedicine reduces cost and eases the deployment of systemsMany commercial wearable BT sensors have appeared in recent years (ECG, glucometers, tensiometers, pulse-oximeters, stehoscopes,…)Commercial GPRS gateways for BT medical sensors Body/Personal Area Networks: piconet of sensors. Many examples in the literature [Lee2006] [Yao2005] [Krco2005] [Dong2004]

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General structure of a medical BAN

Normally, each telemedicine project jointly develops its own sensors and its specific dedicated hardware for the gateway

Sensors

Data logger/

Wireless GatewayCentral Server

BAN

Reception Points

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OBJECTIVES

Definition of a wearable medical Personal Area Networks Goals:

Use/evaluation of commercial smart phones as the master of the sensor piconet Integration of commercial BT biosensors: use of Serial Server Profile (SSP) Adoption of Java (J2ME) to ease software portability

•J2ME: Java Technology for the development of software applications in mobile devices.

Hybrid transmissions (Always Best Connected Paradigm): free mobility of the usersTo enable mobility in the medical monitorDetection/Priority of medical alarms: emission of SMS/MMS

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PROPOSED ARCHITECTURE

SPO2

ECG

GPS

InternetInternet

Medical premises

Wifi

2. CENTRALCONTROL SYSTEM

Intelligent Node (IN)(Smart Phone)

BT Pulse-oximeterGPS

3. CONTROL andMONITORING UNITS

GPRS/UMTS

1. PATIENT BODY AREA NETWORK

Bluetooth ECG Belt

Internet

Smart phone in charge of collecting the signals from wireless sensors

and sending them through an hybrid (GPRS/UMTS/Wifi) system.

It also detects medical alarms (emission of SMS) and enables

remote programming of sensors

Software for the remote control and monitoring of the

BAN. Also portable to a smart phone

In charge of storing biosignals and enabling remote monitoring from any Internet node

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Employed Technologies (I)

IntelligentNode

GPS

Pulse-oximeter

1. Patient Body Area Network)

Central Control Server

Alarm Reception terminals

GPRS/UMTSWiFi

IP overGPRS/UMTS

J2ME

J2ME

Mobile Monitoring units

J2ME

IP

Fixed Monitoring units

SMS/UMTS

Java servlets, applets,

Web page

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Employed Technologies (II)

Smart Phones: Nokia 9500, E61, N93, N95 (Symbian OS)Intelligent Node: J2ME (Java) program, Bluetooth API (JSR-82) for managing BT connections and Wireless Messaging API (JSR-120 & JSR-205) for sending SMSs/MMSs, Security and Trust Services API (JSR-177) to manage encryption.Biosignals are encrypted by means of a symmetric algorithm DES with a prefixed keyProtocols used for transmissions: HTTP commands or TCP or UDP/ IP sockets (configurable)Central Control Server: Apache Server. ServletsMonitoring reception software :

Web interface (with a a Java Applet) available for any browser with RMI support. J2ME midlet in the Mobile monitoring unit

Bandwidth:GPRS: up to 64-144 KbpsUMTS: up to 384-3600 KbpsWifi: up to 11 Mbps (802.11b), up to 54 Mbps (802.11g)

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Employed BT devices (I)

GPS Leadtek 9553XChipset SiRF StarIII Bluetooth v1.2(slave mode, Serial Port Profile)5V rechargeable Battery ± 5%V DC NMEA-0183 Protocol

BluetoothBasics

Frequency Band (ISM) at 2.4 GHz. No licence requiredTransmission Range: 10-100 mRobustness to interferences due to Frecuency hoppingBinary rate: up to 1 Mbps (v 1.1), 2-3 Mbps (v 2.0): far enough for most biosignalsLow consume (acceptable for most external biosensors)Extremely popular technology: in many models of PDA and cell phones

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Employed BT devices (II)

Pulse-oximeter Nonin 4100 (I) & Measurements of Plethismogram, Heart Rate & SPO2Bluetooth v1.1 (slave mode, Serial Port Profile)Power: 2 AA batteries

3 bytes/s (Simple Mode)

375 bytes/s (Verbose Mode) Binary Rate

CorBELT: Bluetooth ECG sensor from Corscience 1 channel ECG lead with dry electrodesMobile event recorder: automatic alarms in case of detecting a cardiac eventPower: 1 AA batteriesSampling rate: 200 Hz (12 bits/sample)

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Monitoring (I): Fixed Control Units

Information is received in a Web page through a reception Java applet.

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Monitoring (II): Mobile Control Units

Screenshots of Mobile Control Monitoring Units

A reception J2ME midlet processes and present the encrypted biosignals

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Detection of Medical Alarms through SMS/MMS The SW in the phone sends a SMS/MMS when an alarm is detected:

GSM/GPRS/UMTS

Reception units

J2ME

NI

GPS

Patient iBAN

Pulse-oximeter

J2ME

MMS Alarm!MMS Alarm!

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Detection of Medical Alarms through SMS/MMS The SW in the phone sends a SMS/MMS when an alarm is detected:

GSM/GPRS/UMTS

Reception units

J2ME

NI

GPS

Patient iBAN

Pulse-oximeter

J2ME

SMS Alarm!SMS Alarm!

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Wireless biosignal emulator (I)

Two main research topics about medical WPANs/WBANs:Scalability: how many sensors can be properly integrated in the BAN?Coexistence: different wireless technology (BT, Zigbee, Wifi) may coexist in the same ISM band

The evaluation of practical application environments for BANs may require utilization in parallel of dozens of biosensors (still far from being economical)Solution: to implement a generic software biosignal emulator: any BT biosensor can be emulated with a device having BT connectivity (e.g.: a laptop with one ore more BT dongles).Presently, the software emulates electrocardiogram (ECG) signals.Signals can be downloaded from an Internet PhysioBank Data Base)

Vast archive of formatted digital recordings of biomedical signals from both healthy and pathological subjects: http://www.physionet.org/physiobank/

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Wireless biosignal emulator (II)

A server module retrieves the Internet data, an emulator module emits them through BT and a reception program receives the signals. All these modules have been also developed with Java technology: a J2EE server and two J2ME midlets.

PhysioBank

Internet

Emulator Midlet

Reception Midlet Server

GPRS/UMTSWifi

J2EE In charge of retreiving the biosignals from the database

It includes a GUI to select the record to transmit. The selected record is requested to the server via an Internet connection (WiFi/GPRS-UMTS), then reformatted and transmitted to the reception midlet

The reception software can be incorporated in IN of the developed iBAN. Consequently this architecture permits to substitute the Bluetooth ECG sensor by any J2ME capable device.

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Conclusions (I)

The system was systematically tested (not with real patients)

Smart phone: good candidate for the role of central node in medical BANs

Advantages

Decrease of cost (not specific hardware is required)

Hybrid communications are natively supported in present smart phones

Familiarity of the patient with this type of devices

Use of Java (J2ME)

Software is easily developed (Easy sinstaxis)

Portability

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Conclusions (II)Disadvantages

Usability problems: need of some user interaction

Monitoring applications carry out tasks considered by operating system as risky for security. Therefore acknowledgement is requested to user before continuing certain actions

This drawback could be avoided by means of a validated certificate

INSTABILITIES of OS (Symbian) in certain phone models (portability is not perfect!)

HAND OFF between technologies and reconnection to BT sensors is slow and still present problems

No all the (low-level) functionalities in the smart-phone are accessible through J2ME

Difficulty of debugging errors en complex J2ME applications

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29th IEEE EMBS Annual International Conference

J2ME and Smart Phones as Platform for a Bluetooth Body Area Network for Patient-

Telemonitoring

Departamento de Tecnología Electrónica. University of MálagaETSI de Telecomunicación, Campus de Teatinos, 29071 – Málaga- SpainE-mail: [email protected], [email protected]

M.J. Morón, J.R. Luque, E.J. Cuberos, A.A. Botella,

E. Casilari, A. Díaz Estrella

UNIVERSITY OF MÁLAGA, SPAINLyon (France), 24th August 2007