P13071 Non-Invasive Blood Glucose Monitor Team Members Faculty - - PowerPoint PPT Presentation

P13071 – Non-Invasive Blood Glucose Monitor

Team Members Jared Bold Yongjie Cao John Louma Andrew Rosen Dan Sinkiewicz

Faculty Advisor Professor George Slack (EE) Customer

• Dr. Jayanti Venkataraman (EE)

Overview

• Develop a non-invasive real time

monitoring system that measures blood glucose

• Improve the accuracy of current

non-invasive measurement system

• Obtain a transmission signal and

perform a vector measurement

Team Roles

John

• Microcontroller

configuration

• RF Simulation
• Procurement

Yongjie

• Schematic and

PCB layout

• PCB Population

Jared

• Microcontroller

programming

• Communication
• Documentation

Dan

• RF Path
• MATLAB development
• Schematic

Andrew

• Project Leader
• Antenna design

and testing

• RF Path
• Calibration

system

Project Needs and Specs

Customer Need Customer Specification Accurate measurement of resonant frequency Accurate to 15 KHz of network analyzer Calibration System Calibration time of < 60 seconds Reflection Antenna Narrow band, with resonant frequency ≈ 1.1 GHz Transmission Antenna Wide band, with minimum bandwidth from 800 MHz to 2 GHz High resolution data Measurement intervals of < 60 seconds Verify antenna performance in real-time Display resonant frequency and sweep data is it is aquired

System Architecture

3.0 Control

USB

Battery Pack Power Regulator Hard Drive (Archive) Plot Data Math Manipulation Port Choice

USB

Level 1 Functional Block Diagram

Resolution

MIcrocontroller

Arm/Sample

RF Synthesizer Antenna (S11) Vector Measurement (AD8302) Antenna (S21) Vector Measurement (AD8302) Harmonic Filters and Gain

Incident Incident Transmitted Reference Reflected Transmitted Reflected

Reset Bi-Directional Coupler Bi-Directional Coupler Low Power Indicator Phase Plane Correction

Concepts – Measurement System

• Critical to operation of device
• Generated the RF signal

at the desired frequency

• Ensured the signal

reaches antenna with maximum power and minimum error

• Measures the reflected

and transmitted signal

Concepts – Data Acquisition

Power Up/Reset Initialize I/O and communication interfaces Sleep Measure Flag Calibrate Flag Measurement done? Set next frequency and collect mag and phase data Transmit data to PC Calibration Complete Indicate to user which RF path and load is being calibrated Set next frequency and collect mag and phase data Transmit data to PC

Microcontroller serves as middleman for device

• Reads the voltage
• utputs from the

AD8302

• Digitizes values and

sends to PC via USB

Concepts – Data Analysis and Display

• MATLAB Measure Command flow chart
• Reads continuous stream of data from device and stores/displays the data in

real-time.

Concepts – Data Analysis and Display

• MATLAB Calibration Command flow chart
• Reads continuous stream of data from device and stores off the calibration

data to be used later to compensate for phase error in measurements

Components – Reflection Antenna

Design and Simulation

Components – Reflection Antenna

Measured Return Loss

Components – Transmission Antenna

Design and Simulation

Components – Transmission Antenna

Measured Return Loss

Components and Layout

• RF Synthesizer – ADF4351
• Vector Measurement – AD8302
• Microcontroller – MSP430F5427A

Testing

Component/System Testing

• Individual testing of each system
• Verification of power supply and regulation
• Communication between MCU and USB
• Communication between board and host PC
• Communication between MCU and RF Synthesizer
• Continuity of RF path and verification of components
• Correct output of when using test signals on the AD8302
• Verification of correct frequency output of RF Synthesizer with spectrum

analyzer

Device Testing

• Test free space resonant frequency
• Test against sugar water
• Three different levels of sugar concentrations
• Solution is comprised of Water = 66.9%, Salt = 0.8%, Sugar = 25%, Flour = 7.3%
• Test against human body
• Use fast acting glucose tablets to raise blood-glucose
• Compare with real blood glucose monitor
• Find a diabetic to make one final test

Results

Success or Failure?

• Overall, the device was designed to meet/exceed the specifications

given

• All aspects of the device function individually, however the design

ultimately does not function. The board was not matched to 50Ω at

• ur designed frequency of 1.1 GHz, making it impossible to determine

the resonant frequency of the antenna.

• We didn’t anticipate the shift in impedance and we could have resolved the

issue with some sort of tuner

800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000

• 200
• 100

100 200 300 400 Input Impedance vs. Frequency Frequency (MHz) Impedance 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000

• 22
• 20
• 18
• 16
• 14
• 12
• 10
• 8
• 6
• 4
• 2

Return Loss (S11) vs. Frequency Frequency (MHz) S11 (dB) Real Imaginary

Matlab GUI

Suggestions for Future Work – Advice to next group

• Have a dedicated QA person for each system of the device
• Ensure that at least one member of the team has RF circuit board

design experience

• Design the board for a smaller bandwidth
• Get the development boards for everything, regardless of cost
• Develop a working product with dev boards and antenna. Then make PCB.
• Buy doubles/extras of all components
• Develop standards for testing procedure

Opportunities for Improvement

• Properly matched RF path
• Make path simpler to remove parasitic effects from chips
• Implementation of a more robust calibration system
• Calibrate out magnitude and phase
• Enhanced communications between MATLAB and device
• On board processing
• 360⁰ Phase measurement using two AD8302s