The document proposes AudioDAQ, a new platform for continuous data acquisition using a mobile phone's ubiquitous headset port. It allows turning the port into a universal data acquisition interface. AudioDAQ uses the microphone bias as a power source and acquires analog sensor data at 1.2 kHz, capturing and storing it as audio files. It was tested with various phones and an EKG sensor, demonstrating functionality while allowing battery life of over 18 hours.

1. May 11. 2013
AudioDAQ:Turning the Mobile Phone’s Ubiquitous
Headset Port into a Universal Data Acquisition Interface
Sonal Verma, Andrew Robinson, and Prabal Dutta
発表者：浅見・川原研
M1 ジュ ヒョンジェ
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2. Sensors Integrated into the Phone
✤ Accelerometers
✤ Gyroscopes
✤ Imagers
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3. Sensors Integrated into the Phone
✤ Accelerometers
✤ Gyroscopes
✤ Imagers
EKG Sensor
Air Quality Sensor
Soil Moisture Sensor
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4. Sensors Integrated into the Phone
✤ Accelerometers
✤ Gyroscopes
✤ Imagers
EKG Sensor
Air Quality Sensor
Soil Moisture Sensor
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5. Mobile Phone’s Headset Port
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6. Mobile Phone’s Headset Port
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7. Mobile Phone’s Headset Port
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✤ Mostly standardized across many mobile phone’s
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8. Existing Phone Peripheral Interfaces
✤ Square card reader
✤ RedEye mini
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9. Existing Phone Peripheral Interfaces
✤ Square card reader
✤ RedEye mini
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What works for sporadic activities
does not scale well to continuous sensing
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10. What is the AudioDAQ ?
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11. What is the AudioDAQ ?
✤ A new platform for continuous data acquisition using the
headset port of a mobile phone.
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12. What is the AudioDAQ ?
✤ A new platform for continuous data acquisition using the
headset port of a mobile phone.
Cost
Simplicity
Ubiquity
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13. Design
✤ ① Hardware Interface
✤ ② Mobile Phone
✤ ③ Processor
✤ ④ End User Applications
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14. Design
✤ ① Hardware Interface
✤ ② Mobile Phone
✤ ③ Processor
✤ ④ End User Applications
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15. Design
✤ ① Hardware Interface
✤ ② Mobile Phone
✤ ③ Processor
✤ ④ End User Applications
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16. Design
✤ ① Hardware Interface
✤ ② Mobile Phone
✤ ③ Processor
✤ ④ End User Applications
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17. Design
✤ ① Hardware Interface
✤ ② Mobile Phone
✤ ③ Processor
✤ ④ End User Applications
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18. Hardware Interface (1)
✤ Microphone Bias as Power Source
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19. Hardware Interface (1)
✤ Microphone Bias as Power Source
7Low pass filter
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20. Hardware Interface (1)
✤ Microphone Bias as Power Source
7Low pass filter
Scaling resistor
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21. Hardware Interface (2)
✤ Acquiring analog sensor data
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22. Hardware Interface (2)
✤ Acquiring analog sensor data
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1.2 kHz
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23. Hardware Interface (2)
✤ Acquiring analog sensor data
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1.2 kHz
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24. Hardware Interface (1)
✤ Acquiring analog sensor data
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25. Hardware Interface (1)
✤ Acquiring analog sensor data
9High pass filter
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26. Capturing and Storing Data
✤ iOS
✤ Advanced Audio Coding (AAC) - 44.1 kHz
✤ Android
✤ Adaptive Multi-rate (AMR) - 8 kHz
✤ Others
✤ Adaptive Multi-rate (AMR) - 8 kHz
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27. Processing Sensor Data
✤ Decoding
✤ Edge Detection
✤ Value Estimation
✤ Framing
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28. Processing Sensor Data
✤ Decoding
✤ Edge Detection
✤ Value Estimation
✤ Framing
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29. Processing Sensor Data
✤ Decoding
✤ Edge Detection
✤ Value Estimation
✤ Framing
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30. Processing Sensor Data
✤ Decoding
✤ Edge Detection
✤ Value Estimation
✤ Framing
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31. Low-Power EKG Sensor (1)
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✤ Block Diagram of the EKG Sensor System
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32. Low-Power EKG Sensor (1)
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✤ Block Diagram of the EKG Sensor System
16$
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33. Low-Power EKG Sensor (1)
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✤ Block Diagram of the EKG Sensor System
8$
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34. Low-Power EKG Sensor (2)
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The AudioDAQ board interfaced with 2-lead EKG sensor
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35. Low-Power EKG Sensor (2)
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EKG trace of an individual
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36. Low-Power EKG Sensor (2)
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EKG trace of an individual
P Wave
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37. Low-Power EKG Sensor (2)
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EKG trace of an individual
Q Wave
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38. Low-Power EKG Sensor (2)
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EKG trace of an individual
QRS complex
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39. Low-Power EKG Sensor (2)
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EKG trace of an individual
T wave
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40. Low-Power EKG Sensor (2)
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EKG trace of an individual
P P
Q Q
R R
S S
T T
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41. Evaluation
- System functionality and Power consumption
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Phone Works Power Sourced Power Drawn Battery Capacity Battery Life (est.)
iPhone4 Yes 322!W 149mW 5254mW 35 hr
Nexus One Yes 168!W 267mW 5180mW 19 hr
Galaxy Nexus Yes 247!W 301mW 6475mW 21 hr
N900 Yes 120!W 270mW 4884mW 18 hr
E71 Yes 90!W 189mW 5550mW 29 hr
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42. Evaluation
- System functionality and Power consumption
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Phone Works Power Sourced Power Drawn Battery Capacity Battery Life (est.)
iPhone4 Yes 322!W 149mW 5254mW 35 hr
Nexus One Yes 168!W 267mW 5180mW 19 hr
Galaxy Nexus Yes 247!W 301mW 6475mW 21 hr
N900 Yes 120!W 270mW 4884mW 18 hr
E71 Yes 90!W 189mW 5550mW 29 hr
Saturday, May 11, 13

43. Evaluation
- System functionality and Power consumption
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Phone Works Power Sourced Power Drawn Battery Capacity Battery Life (est.)
iPhone4 Yes 322!W 149mW 5254mW 35 hr
Nexus One Yes 168!W 267mW 5180mW 19 hr
Galaxy Nexus Yes 247!W 301mW 6475mW 21 hr
N900 Yes 120!W 270mW 4884mW 18 hr
E71 Yes 90!W 189mW 5550mW 29 hr
Saturday, May 11, 13

44. Evaluation
- System functionality and Power consumption
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Phone Works Power Sourced Power Drawn Battery Capacity Battery Life (est.)
iPhone4 Yes 322!W 149mW 5254mW 35 hr
Nexus One Yes 168!W 267mW 5180mW 19 hr
Galaxy Nexus Yes 247!W 301mW 6475mW 21 hr
N900 Yes 120!W 270mW 4884mW 18 hr
E71 Yes 90!W 189mW 5550mW 29 hr
Saturday, May 11, 13

45. Evaluation
- System functionality and Power consumption
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Phone Works Power Sourced Power Drawn Battery Capacity Battery Life (est.)
iPhone4 Yes 322!W 149mW 5254mW 35 hr
Nexus One Yes 168!W 267mW 5180mW 19 hr
Galaxy Nexus Yes 247!W 301mW 6475mW 21 hr
N900 Yes 120!W 270mW 4884mW 18 hr
E71 Yes 90!W 189mW 5550mW 29 hr
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46. Evaluation
- Signal Recovery and Distortion
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A voltage sweep The error component
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47. Limitation
✤ Power Budget
✤ Coupling of Power and Data
✤ Sampling Rate
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48. Conclusion
✤ AudioDAQ
✤ Low cost
✤ Simple, ubiquitous and universal
✤ Low-rate analog sensor data capture, storage, and delivery
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49. Thank you for listening
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