Development Of Awireless Ecg

A REPORT

ON

DEVELOPMENT OF WIRELESS ECG

BY

Key words: ECG amplification circuit, Wireless protocol-

Bluetooth, Interference and noise, future technologies

Abstract: The overall objective of this project is to

design and implement a prototype ECG system which

replaces wired connections between sensor points and a

central node with wireless links. Successful

implementation of the final system would be of benefit

to all involved in the use of electrocardiography as

access to, and movement of, the patient would not be

impeded by the physical constraints imposed by the

cables. Most aspects of the design would also be

portable to other sensor applications, making the work

relevant to a vast range of systems where movement of

sensors is desirable and constrained by hard-wired

links.

The design and implementation of the wireless link and

ECG sensor electronics to produce an ECG signal form

the basis of the Wireless ECG Monitors.

Signature of the students: Signature of the Project faculty

Date: Date:

ACKNOWLEDGEMENTS

We would like to thank our director, Dr. Ramachandran for giving us

an opportunity to undertake this topic as our final year project. We

would like to thank our Project Mentor Dr. D.V.Prasad whose

cooperation has made this project a reality .We would like to thank

Mrs. Swarnalatha for her valuable suggestions throughout this project

term.

We would like to dedicate this project to our family and friends, who

has supported us throughout our studies.

Arunvel Kailasan 2002U8PS012

Mithun Madhavan 2002U3PS041

Table of contents

1]Introduction

1.1]Project Introduction

1.2]Project Requirements

2]ECG BACKGROUND & THEORY

2.1] The Heart

2.2] The ECG Waveform

2.3] Standard ECG Measurement

2.4] Electrodes

3]DESIGN TECHNICAL BACKGROUND

3.1] ECG Sensor Requirements

3.2] Electrodes and Electrode Placement

3.3] The Amplification Circuit

3.3.1] Instrumentation Amplifier

3.3.2] Power Supply

3.3.3] Low Pass Filter

3.3.4] 50Hz Notch Filter

3.3.5] Summing Amplifier

3.4 Digitization of the Analog Signals:

3.4.1] Analog to Digital Converter

3.4.2] Compression

3.4.3] Communication with the Wireless Modules

3.5] PC Software

4]NOISE

4.1] Noise Sources

4.2] AC Mains Interference

4.3] Biological Noise Sources

5]SIGNAL FILTERING

5.1] Analog Filters

5.1.1] Passive Filters

5.1.2] Active Filters

5.1.3] Switched Capacitor Filters

5.2] Digital Filters

5.3] Signal Averaging

5.4] Other noise reduction techniques

5.4.1] ECG Right Leg Driver

5.4.2] Twisted-Pair Wires

5.4.3] Shielded Cables

5.4.4] Differential Inputs

5.5] Compression of Digital Biomedical Signals

5.5.1] Differential Pulse Code Modulation

5.5.2] AZTEC ECG Compression Method

5.5.3] Adaptive Delta Encoding

5.5.4] Frequency-Domain Data Compression

5.5.5] Wavelet / Sub band Coding

6]ECG BIO-POTENTIAL MEASUREMENT FROM INDIVIDUAL

ELECTRODES

6.1] Standard Differential Amplification

6.2] Amplification Method for Ideal Wireless System

6.3] Attempts to make it Work

6.3.1] Noise Attenuation

6.3.2] Making the Noise Common to Both Channels

7]FUTURE CONSIDERATIONS

7.1] Constructing ECG from Individually Measured Electrode Potentials

7.2] Compression Software

7.3] Power Consumption

7.4] PC Software

7.5] Size

7.6] Wireless Transmission

8]CONCLUSION

Table of Figures:

Figure1.1 Node Architectures

Figure 2.1 - The basic cardiopulmonary system

Figure