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Wireless Networks of Intelligent Sensors (WISE)
Electrical and Computer Engineering Dept.University of Alabama in Huntsville
Huntsville, AL 35899
Emil Jovanov
Associate Professor
email: [email protected]
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Evolution of Computer Monitoring
processprocess Signalconditioning
Signalconditioning
Signalconditioning
Signalconditioning
Signalconditioning
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Evolution of Computer Monitoring
processprocess Signalconditioning
Signalconditioning
Signalconditioning
Signalconditioning
Signalconditioning
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Evolution of Computer Monitoring
processprocess Int.sensor
Int.sensor
Int.sensor
Int.sensor
Int.sensor
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Evolution of Computer Monitoring
processprocess Int.sensor
Int.sensor
Int.sensor
Int.sensor
Int.sensor
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Wireless Sensor NetworksNetworks of wireless sensorsData collection, distributed monitoringApplications
military/surveillance, environmental, condition based maintenanceubiquitous computingdisaster managementmedical applications Disaster Management
Condition-based maintenance
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Existing Wireless Sensor NetworksDARPA - SensITSmart Dust - University of California at Berkley
Lasers/RF for wireless communicationVery small wireless devices that can be spread, and then dynamically organize to become a sensor net
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Existing Wireless Sensor NetworksSmart Dust Communication
Infra red (IrDA)/PDAsRF 900 MHz communicationLaser communicationCorner Cube ReflectorLight Receiver Communication
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Existing Wireless Sensor NetworksUCLA
WINS (Wireless Integrated Network Sensors)Embedded processors, multihop network, sensing
Fusing physical and cognitive spacesAssess student learningPosition, orientation, acoustic data
Wireless Sensor Network (WSN)University of Tennessee, Knoxville
Small sensor scattered on or near a road, and detect enemy vehicle activity
WINS, SCADDS
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Oak Ridge National Lab
“Critters on a chip” (bioreporters)“Nose on a chip”“Lab on a chip”
DNA biochip (2D) Flowthrough genosensor (3D), etc.
Medical Telesensors (2x2 mm wireless temperature sensor)
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MedtronicDivision of Cardiology, Univ. of Western OntarioImplantable loop recorderProvides up to 14 months of cardiac monitoring40 minutes of history can be stored after an episodeWeight 17 g, volume 8 mL
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Existing Wireless Sensor NetworksMicrostrain – Wireless Web Sensor Network
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Issues
Battery lifeSizeCommunication rangeAdaptivity/RobustnessSeamless integration
Ad-hoc networksSecurity
Intelligence
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Wireless LAN Protocols
802.11b2.4GHz band, direct sequence spread spectrum
802.11a5.8GHz band, orth. freq. division multiplexing
Bluetooth900MHz & 2.4GHz bands, frequency hopping spread spectrum
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Custom Communication ProtocolsSuper Frame Timing Diagram
19 20 21 22 23 241 2 3 4 5 6 13 14 15 16 17 187 8 9 10 11 12 25 26 27 28 29 30
Slot 5Slot 4Slot 3Slot 2Slot 1
Master Slot
1st Slave
4th Slave
3rd Slave
2nd Slave
TSF
Tslot
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Intelligent medical monitors
Sudden collapse victims, result ofcirculatoryhypoxemictraumatic arrest
estimated mortality 350,000 lives/yeareconomic cost of trauma related injuries $400 billion / year (NIH PA-01-054)
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Intelligent Personal Monitors
Personal serverECG & breathing
sensors
EEG sensors
Movementsensors
Movement sensors
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Solution?
Wireless Personal Area Network of Intelligent Sensors
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Hierarchical Digital Signal Processing
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Problems of existing systems?
Development environmentcustom VLSI, assembler?
Resources for sophisticated real-time processing
memoryspeed
Price
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Wireless Personal Area NetworkWireless network of intelligent sensors
piconetworkMultiple WISE Devices and MOGULs
PERSONAL
SERVERPERSONALAREA
NETWORK
WISE
CENTRAL SITE
SERVER
INTERNET
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Initial WISE Architecture
microcontrollermicrocontroller
wireless wireless transceivertransceiver
ECG amplifierECG amplifier
ECG electrodesECG electrodes
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Wireless Intelligent Sensor WISE
BatteryMicrocontroller
TI MSP430F1498 channel 12-bit AD conv.
AccelerometerMovement detectionAnalog Device ADXL202
TransceiverLINX 916 MHz
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Wireless Intelligent Sensor WISELow power microcontroller TI430F149
16-bit RISC architecture, 60KB flash, 2KB RAMultra-low power consumption (400 µA in active mode, as low as 0.8 µA in standby mode)8 channels (12+2 bit A/D)
Wireless transceiverLINX RF transceiver 916MHz33.6 Kbps data transfer rateadjustable power/range
Biomedical amplifierTeledyne TETMD A110 (ECG/EEG amplifier)custom amplifiers
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Wireless Personal Area Network System with WISE
FixedWISE
Wireless Range ofThe MOGUL
Trajectory ofMovement
MOGUL
Mobile WISE
WirelessLink
Hierarchical Signal ProcessingInternet
Telemedicalserver
Personal Area Network
Personal networkserver
WISE
10 MIPS 10’s mWI
100MIPS 100’s mWII
500 MIPS 100’s WIII
IV
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Wireless PAN configuration
Personal WISENetwork
Personal serverECG & breathing
sensors
EEG sensors
movement sensors
Movement sensors
Internet
movementsensors
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Hierarchical DSP System Design
Constraint programmingset of constraints
Process schedulingPerformance evaluationEnergy profilingIterative process
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III µC
I Workstation
II DSP
Hierarchical process scheduling
ΙΙΙ µC
I Workstation
II DSP
Hierarchical process scheduling
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Time
Price
Power
Exploring the design space
DSPDSP
µµCC
PowerPower
Proc. TimeProc. Time
HierarchyHierarchy
BatteryBatterylifelife
samplingsamplingcyclecycle
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Wearable physiological monitors
ECG (heart activity)myocardial ischemiaarrythmiacircadian rhythm analysis of heart rate variability
EEG (brain activity)epileptic seizure detectiondrowsiness detection
Heterogenous sensors (polygraphy)sleep apnea monitoringphysical therapy feedback for stroke victimsnew generation human-computer interfaces
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Wireless PAN - Applications
Wearable physiological monitorsintelligent monitoring/early warningsdecrease hospitalizations & nursing visits
Intelligent control of medicationsensing, dosing and compliance monitoring
Aids for disabledComputer assisted rehabilitation
stroke victimssupervised heart attack rehabilitation
Battlefield soldier monitoringAdvanced human-computer interfaces
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Currently active WISE projectsWireless Heart Rate Monitor WHRMBreathing monitorPulse oxymeterUSB interfacePower aware kernelOS support for mobile codeWireless data acquisition and processingPortable physical rehabilitation
Accelerometer based monitoring position/forces
WISE Internet server
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Wireless Heart Rate Monitor WHRMDeveloped with Naval Aerospace Medical Research Lab, Pensacola, FL and RPTechnologiesArmy’s project “The War Fighter’s Stress Response”Wireless monitoring (belt), wireless uplink24 hour heart data acquisitioniPAQ PDA used as mobile gateway for data uploadEstimation of stress resistance based on Heart Rate Variability
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Intelligent data acquisition
250 Hz * 2 channels * 2B * 86400 seconds = 84 MB / day
Secondary memory
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PDA based wireless PAN
TETMD bioamplifierWireless module
LINX 916 MHz transceiver
Compaq iPAQ PDA Personal serverInternet connectivity
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Long term breathing monitor
Sensor designChest beltThermistor based differential breathing sensor
Intelligent data acquisition Wireless linkSmart card/flash memory
When_available archiving
Hierarchical processing
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Intelligent CCD Imaging SensorIVIS 1.0 Board
ImagerImagerRSRS--232 XCVR232 XCVR CPUCPU
RegulatorRegulator
SRAMSRAM
CounterCounterJTAGJTAGPortPort
RSRS--232 Port232 Port
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Dynamic Power Measurement
Dynamic power supply current measurement
Resolution 80-200 KHz, 12 bit precision
Power aware RT kernel implementationMicro C/OS II implemented
Energy per taskRealistic battery life monitoring/prediction
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Power Monitoring DeviceReal time dynamic power supply current monitoring
Power efficient computing Resolution 80-200 KHz, 12 bit precisionPower aware RT kernel implementation
Micro C/OS II implemented
Energy per taskRealistic battery life monitoring/prediction
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Emotion (Arousal) Sensing Device
GSR electrodes
Speech processing
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Situational awarenessProblems
mission critical systemslack of spatial and temporal cuesinformation overloading
SolutionPosition sensingSound beaconsprioritized warningsintegrated with command and control system
Mobile networked 3D sound systemElectronic compass
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Future WISE projects
Multimodal guidance systemElectronic compassSound beacon
GPS based control/guidance systemNew wireless communication interface
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ConclusionEnabling technology for a new generation of control&monitoring systems Sensor technology
Implantable sensors as natural extensionSingle chip intelligent sensor (“intelligent patch”)
Optimum drug administrationProlonged monitoringPortable “guardian angel”Research issues
resource allocation constraint solvingpower optimal system organization