ultra low power wireless sensors for e-healthcare -interactive rfid

May 2, 2023 Dr.G.Murugesan 1

Dr.G.MurugesanDr.G.Murugesan Kongu Engineering CollegeKongu Engineering College [email protected]@kongu.ac.in

Ultra Low Power Wireless Sensors for E-HealthCare -Interactive RFID

Introduction

Requirements of Wireless Health Care Devices

Sensing, Processing, and Communicating High performance, Miniature, Lightweight,

Flexible, Reliable, Secure, Power-Efficient and Intelligent : But Low-cost

Non-invasive, Continuous with almost Real-Time updates

“Ultra Low Power Interactive RFID for Wireless Health Care”

May 2, 2023 G.Murugesan 2

Contents

1. Introduction 2. RFID3. Design Challenges4. Enabling Technologies5. Interactive RFID Sensor System6. Passive I.RFID Sensor System7. Wireless ECG Monotiring8. Semi-passive I.RFID Sensor SystemMay 2, 2023 G.Murugesan 3

Wireless Medical Devices


Medical Wireless Risks & Priorities

RiskRisk

Life critical Life critical functions, high functions, high priority alarms, priority alarms, therapy, remote therapy, remote

controlcontrol

Low priority Low priority data, No therapy data, No therapy

or alarmsor alarms5

Shared risk environment

Risk related to device/system intended use, and wirelessly enabled functions and needed performance

Consequences of not getting data across wireless link correctly, timely, and securely

RF Frequencies Used by Wireless Medical Devices


5GHz20%

Other5%

Proprietary/Not

Specified21%

2.4GHz54%

Sir J. C. Bose History of Wireless Communication

First millimeter-wave communication experiment was demonstrated in 1895 by Sir J.C.Bose (Indian)

Bose went to London for lecture tour in 1896 Bose's remote wireless signaling has priority over

Marconi7

http://en.wikipedia.org/wiki/File:Microwave_Apparatus_-_Jagadish_Chandra_Bose_Museum_-_Bose_Institute_-_Kolkata_2011-07-26_4051.JPG

History of Wireless

8

Performance of a Wireless Device and Frequency Band


lower the frequency – farther and better penetrate solid objects.

But GHz bands - greater bandwidth and higher data rates

Public/ Proprietary (Interoperability/Security)ITU-R/FCC - ISM Bands (limited to one-watt power output)

Introduction -RFID IoT – extends Internet to the real physical world with

wireless micro-devices RFID - identifies objects by electromagnetic waves RFID - consists of one or several transponders or tags and

an interrogator or reader Passive - Low cost, small size and unlimited life time Active – Battery, Long distance, reader and a tag , ad-hoc,

high cost, large size and limited life time Semipassive - Trade-off design between cost and function Capacitive or inductive coupling - Hundreds of KHz to

tens of MHz - few hundreds of kbps - shorter than 1 meter Radiative coupling - hundreds of MHz to several GHz



EPC-Electronic Product Code

Application Scenarios of Interactive RFID Sensors - IOT


Real-timeFlexible electrodesComfortAccuracySimultaneous Continuous monitorNo cumbersome wires

Design Challenges

Limited power budget Cost of RFID tags Display size and tag minimization Integrating display - very bulky and

hard tag Transmission efficiency Real time - high data rate Communication latencyMay 2, 2023 G.Murugesan 13

Interactive RFID for HealthCare

RFID tags with sensors and displays UHF/UWB RFID tag replacing UHF

backscattering with UWB transmitter ADC Inkjet printing ECG electrodes Electronic Paper Display (EPD) Throughout is 400 tags/second With 1.5 KHz ECG sampling rate 10 Mb/s UWB pulse rate


Enabling Technologies for Interactive RFID Sensor System

1. Flexible Electronic Paper Display (EPD)

2. UWB Technology3. Flexible Sensors


Flexible Electronic Paper Display (EPD)

a) Electro-phoretic (EP) displayb) Electro-wetting (EW) displayc) Electro-chromic (EC) displayd) Organic LEDe) Cholesteric LCD


Electro-Phoretic (EP) Display

Electronic ink - made up of millions of tiny microcapsules Microcapsule contains positively charged white particles and

negatively charged black particles suspended in a clear fluid With Positive electric Field – white particles move to the top and

visible. Similarly negative electric Field display black.


Electro-Wetting (EW) Display

Modifies the wetting properties of a solid material by voltage

In equilibrium the colored oil naturally forms a continuous film

When a voltage difference is applied across the hydrophobic insulator – displacing the oil and exposing the underlying white reflecting surface


Electro-Chromic (EC) Display

Made up of two adjacent electrodes and a transparent electrolyte covering them.

PEDOT:PSS works as both the electronic conducting and Electrochromic material and transparent.

Applying a driving voltage (1.8 V), the counter electrode is further oxidized and becomes more transparent and becomes blue


UWB Technology

Ultra-wideband Impulse Radio (UWB-IR) using ultra-narrow pulses Mbps data rate and Tens of meters operating range Duty cycle is very low Very low Power Spectral Density (PSD) over very wide bandwidth Without interference Wideband at least 500 MHz in the 3.1 to 10.6 GHz band


Interactive RFID Sensor System

Network Architecture Two-layer asymmetric UHF/UWB RFID network

architecture Otherwise - power-area hungry to communicate

with CCU directly Downlink - reader to tags employs Amplitude-Shift

Keying with Pulse-Interval Encoding (ASK-PIE) Tag side - simple non-coherent envelop detector. Uplink - UWB-IR signals with on-off-keying (OOK)


Interactive RFID Sensor System


Tag Structure

Tag is composed of ASIC Inkjet-printed EC display Flexible sensor UHF antenna UWB antenna Flexible battery Envelope detector (EnvDet) Baseband (BB) circuitry controls OSC- independent on-chip clock UWB transmitter - UWB-IR Power management Unit (PMU) Different energy sources


Passive UHF/UWB RFID Tagwith Printed EC Display


LDO-Low Drop Out

HILD - Harmonic Injection Locked Driver; En/Dis – Enable/Desiable

10s of μW100s of μW

Wireless ECG Monitoring Solutions


System Architecture of the UHF/UWB RFID ECG tag


Flexible dry electrodes are spared from irritation

Performances comparable to commercial wet electrodes

Lightweight

Additive manufacturing

NPS-JL (nano-particle silver inkjetable low temperature ink)

smoother surface, less shrinking

UHF/UWB RFID Communication Process for REAL-TIME ECG

Transmission


Semi-Passive UHF/UWB RFID Tag with Printed ECG Sensor for Healthcare

May 2, 2023 28Successive-Approximation-register ADC (SAR ADC)

Analogfrontend (AFE)


[email protected]

Thank You