CHAPTER ONE

INTRODUCTION

Nowadays people’s expectations in their life quality are increasing as the

technology is improving rapidly. People need an affordable system (smart) that

can make their lives easier more comfortable and offer more safety.GSM based

home automation system is an electrical and electronic system designed to

control home appliance with a mobile phone. The two main technologies

applied in the system are GSM and PLC. GSM stands for global system for mobile

communication and PLC stands for power line communication. In this study

Nokia 6100 is chosen as the GSM phone that receives command and transfers it

to controller. Due to rapidly advancing of mobile communication technology and

widely availability make it possible to incorporate mobile technology into home

automation systems. ’’AT’’ command is used as communication between GSM

phone and microcontroller by passing through a serial interface RS232 with the

help of its driver.

The project is based on the principle of GSM network which enables the

user to remotely control the operations of the appliances by using a mobile

phone. In other word it would transform a normal home into an intelligent

home. The controlling circuit is the most important component in

communication and interface between home appliances. It was implemented by

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using peripheral interface controller (PIC) interfaced to mobile phone. The user

can perform ON/OFF operations of the appliances just by pressing keypad of

mobile phone.

The user sends GSM data in the form of SMS (short message service) message

to switch ON or OFF any appliances at home such as lamp air condition fan and

etc. the appliances may also provide the user with its current ON/OFF status.

The system can be improved to provide the user with information about the

status of each appliance.

PROJECT OBJECTIVES

The objectives of this project are as follows;

1. To design and develop home appliances control system over GSM

network by using a mobile phone.

2. To determine and understand on how the GSM works.

3. To understand the architecture and programming of the PIC.

4. To learn the troubleshooting and techniques.

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SCOPE OF THE PROJECT

The scopes of works in this project are;

1. Mobile phone with SIM card enables the user to remotely control the

operations of the appliances by communication to the GSM modem.

2. GSM modem allows the capability to send and receive SMS to and from

the mobile phone.

3. RS-232 is the basic serial communication cable that will be used to

interface between GSM modem and PIC microcontroller.

4. PIC microcontroller will be interfaced to the control circuit that is

connected to the appliances. It contains the software components

through which the appliances are controlled and monitored.

5. Relay and control circuit used to detect and control the condition of the

home appliances.

OPERATION OF THE SYSTEM

The system works as a remote sensing for the electrical appliances at home or

industry to check whether it is ON or OFF at the same time the user can control

the electrical appliances at home by sending SMS message into the system for

example turning on the AC before returning home. in case of fire/security the

chip will receive signals from the different sensors in the monitoring place and

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acts according to the received signal by sending an SMS message to user’s

mobile phone it also works as automatic and immediate reporting to the user

in case of emergency for home security as well as immediate and automatic

reporting to the fire brigade and police station according to activated sensor to

decrease the time required for tracking action.

A sketch of overall design of the home appliances control using GSM is shown

in the figure below.

RS232 interface

Relay interface

FIG; Simplified block diagram of home appliances

Control using GSM.

ARCHTECTURE OF THE SYSTEM

It can be implemented to any levels of the security system. The architecture of

the system mainly consists of three components the GSM MODEM and the

Mobile

device

(user)

GSM

modem

PIC

Home

appliances

interface circuit that include the different sensors used. The function of the GSM

MODEM is the remote communication between the user and the controller

through the RS232 serial communication standard. The function of the

controller is to continuously check the inputs coming from the different sensor

and send message through the GSM network in case of emergency such that it

acts as a 24hours monitoring and continuously checking for any received

message from the user through the GSM MODEM to switch on the AC for

example.