Design and Evaluation of a Wireless Magnetic-based
This presentation is the property of its rightful owner.
Sponsored Links
1 / 31

Xiaofan Jiang, Chieh -Jan Mike Liang, Kaifei Chen, Ben Zhang, Jeff Hsu PowerPoint PPT Presentation


  • 120 Views
  • Uploaded on
  • Presentation posted in: General

Design and Evaluation of a Wireless Magnetic-based Proximity Detection Platform for Indoor Applications. Xiaofan Jiang, Chieh -Jan Mike Liang, Kaifei Chen, Ben Zhang, Jeff Hsu Jie Liu, Bin Cao, and Feng Zhao Microsoft Research Asia. 20120730-Neight. Outline. MOTIVATION

Download Presentation

Xiaofan Jiang, Chieh -Jan Mike Liang, Kaifei Chen, Ben Zhang, Jeff Hsu

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Xiaofan jiang chieh jan mike liang kaifei chen ben zhang jeff hsu

Design and Evaluation of a Wireless Magnetic-basedProximity Detection Platform for Indoor Applications

Xiaofan Jiang, Chieh-Jan Mike Liang, Kaifei Chen, Ben Zhang, Jeff Hsu

Jie Liu, Bin Cao, and Feng Zhao

Microsoft Research Asia

20120730-Neight


Outline

Outline

  • MOTIVATION

  • PROXIMITY ZONE

  • Empirical Definition

  • EVALUATION OF EXISTING TECHNOLOGIES

  • LIVESYNERGY PLATFORM

  • EVALUATION OF LIVESYNERGY

  • APPLICATION DEPLOYMENT

  • CONCLUSIONS


Motivation

Motivation

  • To make applications intuitive to human users, the discovered objects in the environment must be within the personal interaction sphere

  • Computer automatically wake up

  • Refrigerator change its user interface

  • Many typical low power communication technologies, (Bluetooth, ZigBee) have difficulties maintaining robust communication zones


Contributions

Contributions

  • propose methodologies and systematically compare the proximity zones created by various wireless technologies(BLE, ZigBee, and RFID reader)

  • Design, Implement, and Evaluate a magnetic-induction based wireless proximity sensing platform

  • Deploying LiveSynergy in an real-world application


Proximity zone

PROXIMITY ZONE

  • Boundary sharpness:

    boundary of proximity zone should be binary

  • Boundary consistency:

    detection should be consistent over time


Proximity zone1

PROXIMITY ZONE

  • Obstacle penetration:

    Beaconing node andlistening node can be mobile

    and against obstructions

  • Additional metrics:

    1. Range and geometric shape of zones

    2. Beaconing frequency achievable

    3. Power consumption

    4. Form-Factor of the mobile tag

    5. Cost of overall system


Classi cation of points

Classification of Points

  • Broadcasts at fixed frequency f (packets )

  • P =a point in space at a distance of (, , ) from the beacon


Classi cation of zones

Classification of Zones

  • white/grey boundary:

    {P | Color(P, t, t’) = white}

    {P | Color(P, t, t’) = grey}

    if x,if x’

    represents the decision boundary

  • grey/black boundary:

    if x,if x’


Three proximity zones

Three proximity zones


Proximity zones

Proximity Zones

Questions?


Classi er

Classifier

  • Use support vector machines (SVM) as the classifier

    seeks maximum-margin hyperplane to separate two classes

  • w and b are the parameters to define the hyperplane to separate the two classes.


Classi er1

Classifier

  • Two user-definable parameters:

  • Error tolerance:

    - Smooth boundaryvs. non-smooth boundary

  • Tradeoff between training loss and regularization

  • Cost parameter C

  • Strictness:

    -Expect the white zone and the black zone contain no grey points

    -Related to error tolerance but non-symmetry


Classi er2

Classifier

  • Cost parameter

    C: the cost of false positive

    C’: the cost of false negative C’

  • Strictness parameter:


K ernel trick

Kernel Trick

  • RBF kernel as the kernel function

  • Classifier:

  • RBF kernel


Matrix

Matrix

  • Size:

    Size of the white and grey zone, which can be computed numerically based on the boundaries.

  • Boundary sharpness:

  • Fitness:

    How well the zone boundaries fit the data, or a confidence

    measure of the proximity zone classification.


Classi er3

Classifier

Questions?


Boundary sharpness and consistency

Boundary Sharpness and Consistency

  • Hardware setup:

  • TI CC2540 BLE dev boards (transmitting on 2.4 GHz at 0 dBm),

  • A pair of TelosB motes with 802.15.4-compliant TI CC24240 radio(transmitting on 2.4 GHz at 0 dBm)

  • A Impinj Speedway R1000 RFID reader (transmitting on 902 MHz at 8 dBm)


Boundary sharpness and consistency1

Boundary Sharpness and Consistency

  • Parameters:

  • packet reception data is collected over a period of 200 seconds

  • WPRR using a windows size of 3 seconds and

  • Strictness parameter = 0.99

  • Results:


Boundary sharpness and consistency2

Boundary Sharpness and Consistency


Human obstacle penetration

Human Obstacle Penetration

  • The user carries the receiver in the right pants pocket

    - calculate PRR from 500 packets as the user changes the body orientation by 90 each round at each distance


Additional metrics

Additional Metrics

  • Signal propagation and geometry:

    RFID antennas usually have a radiation angle less than 180 degrees

  • Form Factor and Costs:

    RFID can produce a more consistent and smaller grey zone

    802.15.4 and BLE have advantages in both form factor and costs.


Evaluation

Evaluation

Questions?


Livesynergy platform

LIVESYNERGY PLATFORM

  • Pulse Transmitter:(use AC power)

    Four primary hardware

  • microcontroller (MCU) and radio

  • magnetic transmitter tuned at 125kHz

  • Energy metering

  • mechanical relay foractuation.


Livesynergy platform1

LIVESYNERGY PLATFORM

  • Link Receiver: ( battery-powered)

    Three primary hardware

    9.2cm ×5.8cm × 2.3cm enclosure

  • MCU and radio

  • 3D magnetic coil

  • wake up chip


Boundary sharpness and consistency3

Boundary Sharpness and Consistency


Body orientation vs distance

Body orientation vs. distance

  • human body has very little impact on the MI signal propagation


Additional metrics1

Additional Metrics

  • Geometry:

    two dimensions extends to all directions, covering 360◦

  • Range:

    maximum range (i.e., radius) is around 5m


Application deployment

APPLICATION DEPLOYMENT

Diners enter the cafeteria from the entrance at the lower left corner at different times


Experment

Experment

  • Each diner takes a different route and visits various food counters on the way

  • Recorded a video as the customers walk around the cafeteria purchasing food.

    - Use video timestamps


Result

Result


Summary

Summary

  • Values:

  • Propose methodologies and systematically compare the proximity zones

  • Deploying LiveSynergy in an real-world application

  • Future?

  • MI still can implement in mobile phone…


  • Login