A

Mini-Project Report
On

Li-Fi Based Data Transmission

System for Operation Theatres
SUBMITTED BY

Student name Exam. Seat No.

1. Tanmay Sawaji T1900803163

2. Rohan Rawade T1900803148

3.Rushikesh Alwekar T1900803151

PROJECT GUIDE

Mrs.Usha Jadhav

DEPARTMENT OF ELECTRONICS AND TELECOMMUNICATION

D.Y.PATIL COLLEGE OF ENGINEERING

AKURDI, PUNE – 411044
2024-2025
 D.Y.PATIL COLLEGE OF ENGINEERING
AKURDI, PUNE – 411044

DEPARTMENT OF ELECTRONICS AND TELECOMMUNICATION

CERTIFICATE

This is to certify that Student name – Exam. Seat no. of T.E. E&TC
has completed the mini-project on

Li-Fi Based Data Transmission for Operation

Theatres

satisfactorily under my supervision and guidance and submitted the

project report in complete fulfillment of requirement for the award of
TE (E&TC) Degree of Engineering course under the Savitribai Phule
Pune University, Pune during the academic year 2024-2025.

Mrs.Usha Biradar Dr. Rutuja

Deshmukh
Project Guide H.O.D. E&TC
 D.Y.PATIL COLLEGE OF ENGINEERING
AKURDI, PUNE – 411044

DEPARTMENT OF ELECTRONICS AND TELECOMMUNICATION

CERTIFICATE

This is to certify that following students of T.E. Electronics &

Telecommunication have completed the mini-project on Li-Fi Based Data
Transmission System for Operation Theatres satisfactorily under my
supervision and guidance and submitted the project report in complete
fulfillment of requirement for the award of Bachelors Degree of Engineering
course under the Savitribai Phule Pune University, Pune during the academic
year 2024-2025.

Student name Exam. Seat No.

1.Tanmay Sawaji T1900803163

2.Rohan Rawade T1900803148

3. Rushikesh Alwekar T1900803151

Mrs.Usha Biradar Dr. Rutuja Deshmukh

Project Guide H.O.D. E&TC
 ACKNOWLEDGEMENT

We express our sincere gratitude towards the faculty members who makes this project a
successful.

We would like to express our thanks to our guide Mrs.Usha Jadhav for her whole
hearted co-operation and valuable suggestions, technical guidance throughout the project
work.

Special thanks to our H.O.D. Dr. Rutuja Deshmukh for her kind official support and
encouragement.

We are also thankful to our mini-project coordinators Mrs. Usha Biradar for her
valuable guidance.

Finally, we would like to thank all staff members and faculty members of E&TC
Department who helped us directly or indirectly to complete this work successfully.
 INDEX

Sr. No. Contents Page No.

1. Introduction

2. Literature Survey

3. Problem Statement with Objectives

4. Specifications of Project

5. Block Diagram

6. Circuit Diagram

7. Selection of components, calculations

8. Simulation Results

9. PCB Art work

10. Testing Procedures

11. Enclosure Design

12. Test Results

13. Conclusion

14. References
List of Figures:

Sr. No. Title Page No.

List of Tables:

Sr. No. Title Page No.

1. Introduction :

In today’s technologically advanced healthcare environment,

maintaining reliable and interference-free communication is critical,
especially in sensitive areas like operation theatres (OTs).
Traditional wireless communication systems such as Wi-Fi and
Bluetooth operate on radio frequencies, which can cause
electromagnetic interference (EMI) with life-saving medical
equipment. This interference poses potential risks to both patients and
medical staff. Our project, "Li-Fi Based Data Transfer System for
Medical Applications", offers a secure, low-cost, and EMI-free
alternative using visible light communication (Li-Fi). In this system,
temperature data from a patient is collected using an LM35 sensor
and transmitted wirelessly through an LED acting as a transmitter. A
photodiode (or LDR) at the receiver side detects this data and sends
it to an Arduino for real-time display on an LCD and Serial Monitor.
This project demonstrates a smart solution for wireless monitoring in
EMI-sensitive environments like OTs, ensuring patient safety while
utilizing simple, accessible components. It can also be extended for
other healthcare applications like ICU monitoring, isolation wards, or
remote diagnostics, making it a step toward smarter, safer hospitals
using light-based communication.
2. Literature Survey :
Several studies have explored the potential of Li-Fi (Light Fidelity)
technology as an alternative to traditional wireless communication
systems, particularly in environments where electromagnetic
interference (EMI) is a concern. Hospitals and operation theatres
are among such environments, where the presence of RF-based
devices like Wi-Fi or Bluetooth can disrupt the functioning of
sensitive medical equipment such as ECG machines, defibrillators, or
ventilators.
Li-Fi, introduced by Professor Harald Haas in 2011, uses visible
light communication (VLC) through LEDs to transmit data, offering
a safe, interference-free, and high-speed medium. Since light does
not interfere with electronic devices, researchers have proposed Li-Fi
as a safer alternative for medical data transmission, especially in
areas demanding precision and safety.
Several projects have demonstrated the successful use of Li-Fi for
simple data transmission, such as temperature and humidity
readings. For example, research published in the International
Journal of Engineering Research & Technology (IJERT) shows
implementations using LM35 sensors paired with Arduino
microcontrollers to measure temperature and transmit the data using
LED and photodiode setups. The data is reconstructed on the
receiver side using another Arduino, and displayed on LCD modules
for real-time monitoring.
Other academic projects and IEEE papers emphasize the advantages
of Li-Fi over Wi-Fi in confined or shielded environments, such as
hospitals or aircraft cabins. In one such study, researchers highlighted
that Li-Fi not only eliminates RF interference but also offers added
security, as light cannot penetrate through walls—making it suitable
for transmitting confidential medical data.
Furthermore, advancements in IoT and embedded systems have
enabled more robust Li-Fi systems, where real-time data is collected
using low-cost sensors and microcontrollers and transmitted using
light pulses. These systems are particularly useful for low-data-rate
applications like patient monitoring, where cost, safety, and ease of
deployment are more important than high bandwidth.
Overall, literature suggests that Li-Fi-based communication offers a
promising and cost-effective solution for secure, EMI-free data
transmission in medical fields. Our project builds on this foundation,
utilizing Arduino, LM35, LED, and photodiode modules to
demonstrate real-time, safe temperature transmission in hospital
environments, particularly operation theatres.
3. Problem Statement with Objectives :

In critical environments like operation theatres and intensive care

units, maintaining patient safety is paramount. However, the use of
traditional wireless communication technologies such as Wi-Fi and
Bluetooth can lead to electromagnetic interference (EMI), which
may disrupt the operation of sensitive medical devices like ECGs,
ventilators, and infusion pumps. While wired communication avoids
this issue, it limits mobility, increases clutter, and complicates
emergency responses. There is a pressing need for a safe, EMI-free
alternative for transmitting medical data such as patient temperature
in real time.
To address this challenge, the objective of this project is to design a
low-cost, interference-free, and real-time data transmission
system using Li-Fi (Light Fidelity). The system employs an LM35
temperature sensor to monitor patient temperature, which is
transmitted via a visible light LED and received using a photodiode
or LDR sensor. The data is decoded by a microcontroller and
displayed on both an LCD screen and Serial Monitor for real-time
monitoring.
This project aims to build a compact and efficient prototype that
showcases the potential of Li-Fi for medical data communication in
EMI-sensitive zones. Future objectives include extending the system
to transmit multiple sensor values, improving transmission speed, and
integrating wireless alert mechanisms—all while ensuring low power
consumption and affordability for real-world deployment in smart
hospitals.
4. Specifications of Project :

The Li-Fi Based Data Transfer System for Medical Applications is built using
both hardware and software components that work together to enable real-time
transmission of sensor data without causing electromagnetic interference. At the
core of the hardware setup are two Arduino Uno boards—one acting as the
transmitter and the other as the receiver. The transmitting module collects
temperature data using an LM35 sensor and encodes it into an 8-bit binary format.
This binary data is then transmitted using a high-brightness white LED, which
acts as a visible light source for data modulation. On the receiver end, a
photodiode or LDR module detects the light pulses and converts them back into
digital signals, which are then decoded by the second Arduino. The received
temperature value is displayed on a 16x2 LCD screen for real-time monitoring,
and also output to the serial monitor for verification. The system is powered by a
standard 5V USB or battery source, making it compact and portable for medical
environments.
On the software side, the system is programmed using the Arduino IDE. The
transmitter code reads the analog temperature input from the LM35 sensor,
converts it to Celsius, and sends it bit-by-bit using the LED with carefully timed
delays to maintain data synchronization. The receiver code listens for digital
pulses from the photodiode, reconstructs the 8-bit binary signal, and translates it
back into temperature values. The final value is then updated on the LCD display
every 2 seconds. All communication and debugging are done through the Arduino
Serial Monitor.
At an advanced level, the project is capable of transmitting temperature values
with minimal delay and good accuracy in a low-light environment. It is designed
to be immune to RF interference, making it especially suitable for sensitive areas
such as operation theatres and ICUs where traditional wireless communication
might disrupt critical medical devices. The entire system is modular and scalable,
allowing future integration of more complex sensors, improved data encoding
methods, or even bidirectional communication using light.
5. Block Diagram :
6. Circuit Diagram :
7. Selection of components, calculations :
1. LDR Module (Light Dependent Resistor):
a. Purpose : The LDR module detects light intensity, converting light
signals into electrical signals for the Li-Fi Based Data Transfer System.
b. Key Features:
1. Light Sensitivity: Changes resistance based on light
intensity.
2. Compact Design: Small and easy to integrate.
3. Easy Integration
4. Low power consumption
c. Datasheet & Features:
1. Sensor Type: Photoresistor that adjusts resistance with
light.
2. Operating Voltage: 3.3V to 5V
3. Resistance Range: In darkness, resistance can reach
10MΩ, while in bright light, it can drop to 1KΩ.
4. Response Time: Less than 100ms for detecting changes in
light.
5. Output Type: Analog output varying with light intensity
(0 to 5V).
6. Size: Typically 30mm x 20mm, compact for easy
integration.
d. Pin Diagram :
2. 16x2 LCD with I2C Module:
a. Purpose:
1. The 16x2 LCD with I2C is used to display messages and
alerts to the user, such as "Drowsiness Detected!" or
"Alert !", based on the system’s detection logic. It acts as a
visual interface in the sleep detection and alert system. By
using the I2C module, we reduce the number of wires
needed to interface with the ESP32-CAM from 16 to just 2
data pins (plus VCC and GND), simplifying the
connection.
b. Key Features:
1. Alphanumeric display: 16 characters x 2 lines.
2. I2C interface: Uses only two data pins (SDA and SCL) to
communicate.
3. Adjustable backlight and contrast: Via onboard potentiometer.
4. Low power consumption.
5. Simple 4-wire connection: VCC, GND, SDA, SCL.
6. Compatible with many microcontrollers including
ESP32,Arduino, etc.
c. Datasheet & Feature :
🔹 LCD Display Module (HD44780-based):
a. Operating voltage: 5V
b. Number of characters: 16 per row x 2 rows
c. Character size: 5x8 dot matrix
d. Display color: Usually green or blue backlight with
white text
e. Communication: Parallel (natively), adapted to I2C
via backpack module
f. Contrast control: Onboard potentiometer
 🔹I2C Backpack Module (PCF8574 I/O Expander Chip):
g. Operating voltage: 5V
h. I2C address: Usually 0x27 or 0x3F (can be changed
via jumpers)
i. I2C speed: Standard 100kHz or Fast-mode 400kHz
j. Built-in pull-up resistors on SDA/SCL lines
k. 8-bit I/O expander: Converts serial data to parallel
data for the LCD
d.Pin Diagram :

LCD WITH I2C

3. Temperature Sensor (DHT11):

a.Purpose : Measures temperature and humidity for monitoring
environmental conditions in real-time.
b. Key Features:
1. Measures temperatures from 0°C to 50°C with an accuracy
of ±2°C.
2. Provides a direct digital output for easier integration
 3. Consumes less than 2.5mA

c.datasheet & Features:

1. Input Voltage: 5V
2. Temperature accuracy: ±2°C.
3. Size: 27mm x 15mm

d.Pin Diagram :

DHT11

4. Arduino Uno:
a.Purpose : microcontroller for controlling and interfacing
b.Key Features:
a. 8-bit microcontroller with 32KB flash memory.
b. Clock speed : 16MHz
c. 14 Digital I/O pins , 6 PWM pins
d. Operates on 5V DC or via a USB connection.

c.Datasheet & Features:

1. Operating Voltage: 5V.
2. Flash Memory: 32KB, with 0.5KB used for bootloader.
3. SRAM: 2KB of SRAM.
4. EEPROM: 1KB of EEPROM storage.
 5. Clock Speed: 16MHz
d.Pin Diagram :

Arduino uno

4. LED (Light Emitting Diode):

a.Purpose :
1. In your sleep detection and alert system , an LED can be
used to give visual alerts—such as blinking when
drowsiness is detected or to show system status (e.g.,
system active, standby, alert, etc.).

b.Key Features:
2. Emits visible light when powered
3. Low power consumption
4. Long lifespan
5. Quick response time (lights up instantly)
6. Different colors available (Red, Green, Blue, White, etc.)
7. Requires current-limiting resistor (commonly 220Ω or
330Ω)

c.Datasheet & Features:

Polarity:
 a. Anode (+): Long leg – connect to positive
via resistor
b. Cathode (–): Short leg – connect to GND

d.Pin Diagram :

LED
Note: Students should write the references as per the format given
below

References
(Minimum 10 references are required as per
HOD instruction)
 Papers
1. Author name, “name of paper”, name of journal, Issue no, Volume,
page no.,year of publication
 Books
1. Author name, “name of book”, name of publisher, edition
 Website

Format Instructions:

Font:Times New Roman

No page borders
1) Heading=size:16
2) Sub heading=size:14
3) All text=size:12
4) Caption for tables(on top of tables, to be centered):10 bold
5) Caption for figures(at bottom of figures, to be centered):10
bold , italic
6)page numbers at bottom right extreme
(should start only from chapter 1)
7) Header: right aligned: Title of project
8) Footer : Left aligned: DYPCOE, Departmentof E&TC
9) Whole document should be justified(option in paragraph menu
or ctrl +j)
10) Line spacing 1.5