final year report 1

8/10/2019 Final Year Report 1

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DECLARATION

Certification

Statement of Authorship and Originality.

I declare that this report and the work described in it are my own work, with any

contributions from others expressly acknowledged and/or cited.

I declare that the work in this report was carried out in accordance with the Regulations ofthe University of Dar es Salaam and has not been presented to any other

University for examination either in Tanzania or overseas. Any views expressed in the

report are those of the author and in no way represent those of the University of Dar es

Salaam.

SIGNED:........................................................

DATE:..........................

This report may proceed for submission for assessment for the award of

B.Sc. in Telecommunications Engineering at the University of Dar es Salaam.

Review Committee Signature:.......................... Date:..........................

Supervisor Signature: ........................ Date:..........................


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ABSTRACT

This project is designed to make home appliances easy to control when a user is not at home.

The need for being physically present to control these appliances is eliminated by

application of this project. A project design and implement home appliances control system.

Using a mobile phone the development of the control system will be carried out using SMS.

This will communicate with a GSM modem, which in turn controls the devices attached to

microcontroller modules. When the action has been carried out then a response is sent back

to the user to give feedback about the status of the appliances.

I have achieved to specify requirements of the system, designing and analyses several parts

of the system .

This report consists of four chapters; Chapter 1 explaining Introduction about the project,

Chapter 2 explaining Literature review, Chapter 3 explaining Requirement capture, analysis

and designing and Chapter 4 explaining Conclusion and Recommendation.


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ACKNOWLDGEMENTS

First of all I would like to thank the almighty God for keeping me strong both mentally

and physically during the development of my project from the early stages up to this

point when I am completing this report.

I would like to sincerely extend my heartfelt appreciation to my project supervisor

Dr. Massawe for being extremely supportive to me in carrying out my project. His advices

and recommendations have been vitally significant for the progress of my project.

A lot of thanks should also go to all the instructors from the College of Information and

communications Technologies for the knowledge obtained from them has been helpfuland greatly applicable in my project.

I also thank my fellow students, friends and family. Their material and moral

support is hugely appreciated as it has played a major role in my project.

For anyone who has played part in helping me in my project to this point but has not been

mentioned in this page, it does not mean your assistance is not appreciated; you areall honored for your contribution. Blessed be you all for your assistance.


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TABLE OF CONTENTSUNIVERSITY OF DAR ES SALAAM ................................................................................................. i

DECLARATION ................................................................................................................................... ii

ABSTRACT ......................................................................................................................................... iii

ACKNOWLDGEMENTS .................................................................................................................... iv

LIST OF SYMBOLS, ABBREVIATION AND NOMENCLATURE ............................................... vii

LIST OF FIGURES .............................................................................................................................. ix

LIST OF TABLES ................................................................................................................................. x

CHAPTER ONE .................................................................................................................................... 1

1.1 BACKGROUND ......................................................................................................................... 1

1.2 MOTIVATION ............................................................................................................................ 11.3 PROBLEM STATEMENT .......................................................................................................... 1

1.4 OBJECTIVES .............................................................................................................................. 2

1.4.1 Main objective ...................................................................................................................... 2

1.4.2 Specific objectives ................................................................................................................ 2

1.5 METHODOLOGY ...................................................................................................................... 3

1.5.1 Literature reviews ................................................................................................................. 3

1.5.2 Problem analysis and requirement specifications ................................................................ 3

1.5.3 System design and analysis .................................................................................................. 3

1.5.4 Implementation ..................................................................................................................... 3

1.5.5 Testing of the system ............................................................................................................ 3

CHAPTER TWO ................................................................................................................................... 4

2.1 INTRODUCTION ....................................................................................................................... 4

2.2 EXISTING SYSTEM .................................................................................................................. 4

2.3 GSM TECHNOLOGY AND SHORT MESSAGE SERVICE ................................................... 5

2.3.1 GSM technology .................................................................................................................. 5

2.3.2 Basic Specification in GSM ................................................................................................ 7

2.3.3 Short Message Service .......................................................................................................... 8

2.3.4 What makes SMS messaging so successful worldwide? ..................................................... 9

2.3.5 Short Message Service Center (SMSC) ............................................................................. 10

CHAPTER THREE ............................................................................................................................. 12

3.1 INTRODUCTION ..................................................................................................................... 12


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3.2 SYSTEM REQUIREMENTS AND SPECIFICATIONS ......................................................... 12

3.2.1 Functional requirements and Specifications ....................................................................... 12

3.2.2 Hardware and Software requirements ................................................................................ 13

3.3 SYSTEM ANALYSIS ............................................................................................................... 14

3.3.1 Block diagram analysis ....................................................................................................... 14

3.4 DESIGN AND DESIGN SPECIFICATIONS ............................................................................... 17

HARDWARE PART ....................................................................................................................... 17

3.4.1 Power supply module: ........................................................................................................ 17

3.4.2 Notification module: The Buzzer ....................................................................................... 18

3.4.3 Appliance module: .............................................................................................................. 20

3.4.4 Control module ................................................................................................................... 20CHAPTER FOUR ............................................................................................................................... 22

4.1 WORK DONE SO FAR ...................................................................................................... 22

4.2 FUTURE WORK ................................................................................................................ 22

4.3 CONCLUSION ................................................................................................................... 22

4.4 RECOMMENDATION ....................................................................................................... 22

REFERENCES .................................................................................................................................... 23

APPENDICES: .................................................................................................................................... 24

APPENDIX A: PROJECT TIME SCHEDULE .............................................................................. 24

APPENDIX B: PROJECT TIME SCHEDULE .............................................................................. 25

APPENDIX C: COST ESTIMATIONS .......................................................................................... 26


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LIST OF SYMBOLS, ABBREVIATION AND NOMENCLATURE

AC - Alternating Current.

BTS -Base Transceiver Station

DC - Direct Current.

ETSI - European Standard Telecommunication standard.

GSM - Global System for Mobile communication.

HLR - Home Location Register

ISDN- Integrated Switched Digital Network

I/O - Input/output.

LCD - Liquid Crystal Display.

MODEM - Modulator/Demodulator.

MSC - Mobile Switching Center.

OMC - Operation and MaintenanceCenter

PC - Personal Computer

PIC - Programmable Interrupt Controller.

PSTN- Public Switched Telephone Network .


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Rx- Receiver

SIM - Subscriber Identity Memory.

SMS - Short message Services.

UART -Universal asynchronous Receiver/Transmitter

Tx - Transmitter

VLR - Visitor Location Register.


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LIST OF FIGURES

Figure2.1: GSM Architecture . 6

Figure 3.1: Block diagram showing the hardware components arrangement 14

Figure 3.2: Block diagram of a linear power supply .. 17

Figure 3.3: Power supply circuit.. 18

Figure 3.4: buzzer simulation circuit 19

Figure 3.5: Specifications of the buzzer 20

Figure 3.6: Appliance interface circuit ..20

Figure 3.7: The microcontroller PIC 16F876A ..21


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LIST OF TABLES

Table 2.1 GSM Air Interface Specificatio ns ..7

Table 3.1: Hardware requirements and their specifications ..13

Table 4: Project schedule for semester 1 ...24

Table 4.2: Project schedule for semester 2 25

Table 4.2: Cost estimates for the project 26


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CHAPTER ONEINTRODUCTION

1.1 BACKGROUND

Home appliances are necessities to help us survive in our busy lifestyles and also to enjoy

more time with our family and friends. A desire to improve lifestyle a system can be

formulated to control these household utilities. The motivation is to facilitate the users to

automate their homes having ubiquitous access. Now a days most of the systems are

automated in order to face new challenges and achieve present day requirements. Automated

systems have less manual operations so that the flexibility, reliabilities are high and accurate.

Everyone will find these items making their lives easier and be more appreciated.

This project is about designing a control system to make home appliances easy to control

when a user is not at home. The system is a GSM based control system, using a mobile

phone the development of control system will be carried out using SMS.

1.2 MOTIVATION

I take this project as challenge case study but also home appliances users should no longer

worry about the state of the appliances to whether to switch ON/OFF or do other functions

when they leave the house as this project come with a scientific solution of controlling home

appliances remotely.

1.3 PROBLEM STATEMENT

Home appliances have become unavoidable appendages in our lives in the present day hectic

lifestyle. Super energy efficient models of every appliance out there use less energy, and

therefore enable the customers to save money. People are willing to pay more for these

particular appliances, because in the long run, they're actually saving a lot more money than

they're spending [1].

With the technological advances of today's appliances, people are obviously drawn to these

products. As we are using them every day to simplify our daily chore, a user may forget to

manually switch off when he/she left at home. Excessive electrical power is going to be

consumed with no purpose. With the development of this project those bills from excessive


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electrical power consumption are going to be reduced by developing an automatic system for

controlling home appliances using mobile phone messages and this will ultimately save a lot

of time because dont have to come back for simple things such as to turn OFF/ON switches

at their home once they go to their respective work.

In addition, a user can take advantage of that in such a way that a person getting off the

office does not get melted with the hot climate as he/she can be able to control different

states of appliances.

1.4 OBJECTIVES

1.4.1 Main objectiveThe project is aimed at designing and implementing the use of mobile phone messages to

remotely control home appliances.

1.4.2 Specific objectives

The specific objectives are:

Designing a microcontroller based system that will be programmed to receive

instructions and commands from a mobile phone over the GSM network and execute

them accordingly to control home appliances; a microcontroller will communicatethe status of an appliance back to a mobile device lighting system.

Interfacing GSM Module with a microcontroller. Interfacing Microcontroller and Home appliances.


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1.5 METHODOLOGY

There are several known control system development approaches and methodologies, but

my project will rely on decomposition down into modules and examining them how they

relate to each other.

The following basic steps or approaches will be applied:

1.5.1 Literature reviews

In this approach, I will be reviewing some of the literatures like GSM and SMS

TECHNOLOGY books. I will also consult with my supervisor hand to hand in order to get

the necessary corrections and guidance on the project progress. In addition to that I will also

consult other lectures and experts in the best way possible.

1.5.2 Problem analysis and requirement specifications

In analyzing the problem I will be looking on the current existing system and understand its

limitations and knowing what should be added to improve the system or develop a new

system and meet my objectives.

1.5.3 System design and analysis

Designing block diagram of the system and analyze it block by block called modules.

1.5.4 Implementation

Implementation of a design into a proper working system-this will involve hardwareinterconnections and software simulations as appear in a design part to form a well workingsystem.

1.5.5 Testing of the system

This is to check if the system is properly working and meet the objectives and retesting will

be done if the functionality and performance requirements have not been full filled.


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CHAPTER TWO

2. LITERATURE REVIEW

2.1 INTRODUCTION

This part explains the original existing systems, their features, working principles,

limitations and advantages and disadvantages of it, it also explains GSM and SMS

technology.

2.2 EXISTING SYSTEM A manual control exists where a user has to be near the appliances to switch ON/OFF

appliances for the usage and to keep track of the status of the appliances a user also has to

come from where he/she is to switch ON/OFF the intended appliance, its advantages is that

a user is assure of total control regardless of any conditions such as network problems,

disadvantage is that this may be wastage of time and uneasy lifestyle as a user will find

having these appliances as a burden.

Infrared remote control system. The use of electronic controllers for controlling electrical

home appliances can be found widely around the world especially in the developed

countries. By time, wireless technology such as infrared light communication. This wireless

technology is widely commercialized and can be found almost anywhere. Though appealing,

it still has a weakness due to the use of infrared light as data transmission medium. When

there are objects blocking the infrared receiver, the process of communication. Nowadays,

almost every equipment and controlling those electrical appliances becomes difficult due to

the point-to-point or line-of-sight communication mode [2]. From this situation, came the

idea to create a wireless electronics control system utilizing Bluetooth technology for data

transfer and control of electrical appliances [2].

Home appliances control system with cellular phone via Bluetooth, in this project, a systemthat uses the application of wireless Bluetooth as data transfer medium was built. Bluetooth

technology operates over unlicensed, universally available frequency of 2.4 GHz, it can link

digital devices within a range of 10m at the speed of 1Mbps[3], the process of controlling

these appliances became easy and more automatic compared to use of infrared and manual

control due to the advantage of no need of the point-to-point or line-of-sight communication


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mode. But this system was limited to a Personal Area Network due to a small available

range for Bluetooth wireless device to communicate (10m-15m maximum).

2.3 GSM TECHNOLOGY AND SHORT MESSAGE SERVICE

2.3.1 GSM technology

GSM is a global system for mobile communication GSM is an international digital

cellular telecommunication. The GSM standard was released by ETSI (European Standard

Telecommunication Standard) back in 1989. The first commercial services were launched

in 1991 and after its early introduction in Europe; the standard went global in 1992.

Since then, GSM has become the most widely adopted and fastest-growing digital cellular

standard, and it is positioned to become the worl ds dominant cellular standard.

Toda ys second-generation GSM networks deliver high quality and secure mobile voice

and data services (such as SMS/ Text Messaging) with full roaming capabilities across

the world.

GSM platform is a hugely successful technology and as unprecedented story of global

achievement. In less than ten years since the first GSM network was commercially

launched, it become, the world s leading and fastest growing mobile standard, spanning

over 173 countries. Today, GSM technology is in use by more than one in ten of the

world s population and growth continues to sour with the number of subscriber

worldwide expected to surpass one billion by through end of 2003.

Toda ys GSM platform is living, growing and evolving and already offers an expanded

and feature-rich famil y of voice and enabling services

The Global System for Mobile Communication (GSM) network is a cellular

telecommunication network with a versatile architecture complying with the ETSI GSM

900/GSM 1800 standard. Siemen s implementation is the digital cellular mobile

communication system D900/1800/1900 that uses the very latest technology to meet

every equipment of the standard.


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Figure2.1:GSMArchitecture


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2.3.2 Basic Specification in GSM

S.N. Parameter Specifications

1 Reverse Channel frequency 890-915MHz

2 Forward Channel frequency 935-960 MHz

3 Tx/Rx Frequency Spacing 45 MHz

4 Tx/Rx Time Slot Spacing 3 Time slots

5 Modulation Data Rate 270.833333kbps

6 Frame Period 4.615ms

7 Users per Frame 8

8 Time Slot Period 576.9microsec

9 Bit Period 3.692 microsecond

10 Modulation 0.3 GMSK

11 ARFCN Number 0 to 124 & 975 to 1023

12 ARFCN Channel Spacing 200 kHz

13 Interleaving 40 ms

14 Voice Coder Bit Rate 13.4kbps

Table 2.1 GSM Air Interface Specifications.

2.3.3 GSM Services

GSM services follow ISDN guidelines and classified as either tele services or data

services. Tele services may be divided into three major categories:

Telephone services, include emergency calling and facsimile. GSM also

supports

Videotex and Teletex, though they are not integral parts of the GSM standard. Bearer services or Data services, which are limited to layers 1, 2 and 3 of the

OSI reference model. Data may be transmitted using either a transparent


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mode or nontransparent mode.

Supplementary ISDN services, are digital in nature, and include call diversion,

closed user group, and caller identification. Supplementary services also

include the short message service (SMS).[4]

2.3.3 Short Message Service

SMS stands for Short Message Service. It is a technology that enables the sending and

receiving of message between mobile phones. SMS first appeared in Europe in 1992. It

was included in the GSM (Global System for Mobile Communication) standards right atthe beginning. Later it was ported to wireless technologies like CDMA and TDMA. The

GSM and SMS standards were originally developed by ETSI. ETSI is the abbreviation

for European Telecommunication Standard Institute. Now the 3GPP (Third Generation

Partnership Project) is responsible for the development and maintenance of the GSM and

SMS standards.

One SMS message can contain at most 140 bytes (1120 bits) of data, so one SMSmessage can contain up to:

160 characters if 7-bit character encoding is used. (7-bit character encoding

is suitable for encoding Latin characters like English alphabets).

70 characters if 16-bit Unicode UCS2 character encoding is used. (SMS text

messages containing non-Latin characters like Chinese character should use

16- bit character encoding).

Once the message is sent the message is received by SMSC, which must then get it to the

appropriate mobile device. To do this the SMSC sends a SMS request to Home Location

Register (HLR) to find the roaming customer. Once HLR receives the request, it responds

to the SMSC with the subsc ribers status:

1. Inactive or active

2. Where subscriber is roaming.

If the response is inactiv e, then the SMSC will hold onto the message for a period of

time. When the subscriber access his device, the HLR sends a SMS notification to the

SMSC and the SMSC will attempt delivery.


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These companies are called SMS service providers.

SMS service providers are also known as SMS gateway providers, SMS resellers and

SMS brokers because of the following reasons:

SMS gateway providers-: An SMS service provider provides an SMS

gateway for its user to send SMS message to. This SMS gateway will then

route the SMS message to another SMS gateway or SMSC.

SMS reseller and SMS broker-: SMS service provider buy a large amount

of SMS message from a lot of wireless carrier at low price per SMS

message. They then sell the SMS message at a price higher than the cost.

Another advantage of using the SMS connectivity services of SMS service providers isthat their network coverage is very good. They work hard to cover as many wireless

networks as possible so as to make their services attractive.[5]

2.3.5 Short Message Service Center (SMSC)

SMSC is a combination of hardware and software responsible for the relaying and storing

and forwarding of short message between an SME and mobile device.

The SMSC must have high reliability, subscriber capacity, and message throughput. In

addition, the system should be easily scalable to accommodate growing demand for SMS

in the network.

Normally, an IN-based solution will allow for a lower entry cost compared pointing

solutions because it can support other applications on single hardware platform and share

resources, thereby spreading the deployment cost over several services and applications.

Another factor to be considered is the ease of operation and maintenance of the

application, as well as the flexibility to activate new services and upgrade to new

software releases.

Nepal has two mobile companies

Nepal telecommunication Spice Nepal Pvt.Ltd.

Both companies have their own SMSC. Nepal telecommunication has +9779851028801.

Similarly Spice Nepal Pvt. Ltd. has +9779800009000


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4.1.4 Short Message Peer to Peer Protocol

The short message peer to peer protocol (SMPP) is a protocol for exchanging SMS

messages between SMS peer entities such as message service centers. It is often used to

allow third parties (e.g. content suppliers like news organizations) to submit messages,

often in bulk.

The protocol is based on complimentary pairs of request / response PDUs exchanged

over OSI layer 4 (TCP/IP session or X.25 SVC3) connections. PDUs are binary encoded

for efficiency.


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CHAPTER THREE

3. REQUIREMENT CAPTURE, SYSTEM DESIGN AND SPECIFICATIONS

3.1 INTRODUCTIONThis chapter will describe how the features and functions of SMS based control system will

be developed. The stated problem will be decomposed into smaller modules and working on

individual modules one after another and at the end, this chapter will responsible to answer

the following important questions:

What are the general system requirements? What are the general specifications for the system? Which features and functions are to be developed? How will be the flow chart of the control unit system? What are the design specifications for the modules?

3.2 SYSTEM REQUIREMENTS AND SPECIFICATIONS

3.2.1 Functional requirements and Specifications

The system should meet the following specifications and functional requirements for the

user to avail the great advantage of this system:

The system will consist of three parts (sub systems) which are Cellular phone-

sends and receives text messages from control unit, control unit-communicate

with a network sends instructions to the appliances and response back to the

cellular phone and appliances-a controlled part.

There will be two operating environments .The cellular phone will operate indoors

and outdoors whereas the control unit will operate indoors within the temperature

and humidity limits for proper operation of the hardware.

The system will be multi-function appliance control, means appliance which

needs other functions rather than ON and OFF, example bulb control for home

uses can be ON, OFF or DIMMED.

The system will control two home bulb appliances by switching them ON and

OFF and change intensity of light.


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The control unit will have the ability to connect to the cellular network

automatically.

The control unit will control the electr ical appliances by issue commands

to the electrical appliances through a simple control circuit.

The microcontroller within the control unit should be able to detect the status of

the appliances and send status messages back to the cellular phone through the

cellular network.

The system should provide user authentication through cell phone number

identification and/or password verification contained within the (SMS) text

message.

The system should have useful features such as notification of signal strength

of the network used by modem and power status of the system to make it reliable.

3.2.2 Hardware and Software requirements

The control system will require a minimum of the following hardware and software

requirements:

Hardware:

Hardware Required Specifications

1. Microcontroller PIC 16F876A

2. GSM Modem Siemens GSM/GPRS

Smart Modem

3. Mobile phone Nokia phone

4. Resistor MINRES6K2,MINRES7K5,

MINRES9K1

5. Transistor

6. LCD

7. Diodes

8. Thyristor and Relays

9. Bulbs 240 V AC bulb


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Table 3.1: Hardware requirement and their specifications.

Software:

i. KEIL VISION Software

This is the software which will be used for writing the application program

software of the microcontroller.

ii. ATMEL programmer.

This is the software used to load the program to the microcontroller.

iii. Proteus schematic software:Is used for designing the circuit diagram for this project which will further be

simulated.

3.3 SYSTEM ANALYSIS

3.3.1 Block diagram analysis

Figure 3.1: Block diagram showing the hardware components arrangement.

CELLULAR PHONE

GSM NETWORK GSM MODEM

A P P L I A N C E 2

( B U L B 2 )

APPLIANCE 1( BULB 1 )

RELAY ANDTRIAC

CONNECTIONS

BUZZER

POWERSUPPLY

LCD DISPLAY

M I C R O C O N T R O L L E R


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Power Supply:

Power supply provides regulated (step-down rectified) DC power supply from AC mains to

circuit components (ICs, relays, microcontroller and other components of the system).

The buzzer:

The buzzer is a device which when activated it produces an audible tone. It will be used in

this system to produce notifications about signal strength of the mobile of the system in

audible sound form.

It will be connected to one of microcontroller output pin. So microcontroller will give high

or low signal to switch on/off buzzer. For example, the buzzer will sound every time the

signal strength of the network used by modem is low or there is power cut to the system

from power supply due to the electric failure.

GSM modem

In the proposed system, modem is used to made communication between the microcontroller

and the user mobile (cellular) phone via GSM network. It will be connected to

microcontroller pins and has a SIM card in it so as to act as a GSM node. GSM modem

receives the SMS sent by the user who wishes to operate any of the connected appliances

and then forwards it to the microcontroller. The microcontroller will initiate messages every

time a change is done in the appliances by providing their status, and then the modem will

forward this message to the mobile phone of the user.

Mobile phone:

In this system the mobile phone will be used by user of the system to remotely communicate

with the GSM modem. It will be used for sending the text message to ask for the status

and/or to do the controlling actions such as switching ON/OFF the bulb or controlling

intensity of the bulb. Also the mobile phone will receive various status messages from the

controller side to indicate any change of the appliances status.


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LCD display:

It will be used to display the status of the operation performed by microcontroller (status of

the appliances) and makes overall system user friendly.

Microcontroller:

The microcontroller is the central brain of the system, and it acts as the controller of all

actions in the system. The microcontroller will be connected to other blocks through its pins

and reads various signals from those parts, interprets them and perform the required action

by sending an appropriate signal to the respective device through output pins.

To enable communications with remote mobile phone, the microcontroller is connected to aGSM modem in one of its pin. Whenever a user wants to change the status of the appliances

he/she sends a message to the GSM modem using a mobile phone, a microcontroller decodes

the received messages and sends the appropriate instructions to appliances to control them

by either switching ON/OFF or change intensity of light for bulb or speed of the fan.

Microcontroller also monitor completion of actions controlled and send the status of the

appliances back to the mobile phone of a user.

Relay and TRIAC connections:

Relay is used to isolate one electrical circuit from another. It allows low current control

circuit to make or break an electrically isolated high current circuit path; this will enable it to

act as a switch in our system to switch ON/OFF appliances.

TRIAC is a semiconductor device which has ability of changing conductivity through the

two terminals depending on the triggering levels of the gate. It starts conducting when there

is enough voltage passing through the gate, by utilizing that ability digital switching betweenspeeds can be implemented and variation of intensity of the bulb can be achieved.

Relay and TRIAC connections will enable our system to be able to switch ON/OFF

appliances and perform another control such as change intensity of bulb, speed of the fan.


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Appliances:

Are the controlled household utilities, can be switched ON/FF or changed to any status

depending on the user requirements.

3.4 DESIGN AND DESIGN SPECIFICATIONS

The designing of the system begins hardware design followed by the software design in

order to optimize design result and still satisfy requirements. Hardware and software

integration is done after hardware and software detail design. Finally system testing is

carried out. In this first project I will do hardware design.

HARDWARE PART

This section deals with the physical components and their specifications that will be used in

SMS Remote controller. This section divided into five subsections which are:

Power supply module Notification module Appliance module Control module Display module GSM modem module

3.4.1 Power supply module:

The maximum and minimum voltage ratings are taken into consideration while designing

power supply.

A 0-12V/500 mA transformer is used for this purpose

The 7805/7812 voltage regulators which are used to provide 5V/12V outputrespectively.

This should provide DC voltage of +5V and +12V to the components

AC power DC

output

Rectifier, Filter(AC TO DCADAPTER)

Regulator

(7805/7812)

Filter


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Figure 3.2: Block diagram of a linear power supply

The following is the simulated schematic of the power supply that produces a regulated 5V

and 12V DC using IC voltage regulator 7805 and 7812.

Figure 3.3: Power supply circuit.

The primary of the transformer is connected in to main supply through on/off switch& fuse

for protecting from overload and short circuit protection. The secondary is connected to the

bridge rectifier to convert 12V AC to 12V DC voltage. And filtered by the capacitors, which

is further regulated to +5v, by using IC 7805 and 12V by using IC 7812 voltage regulator.

3.4.2 Notification module: The Buzzer

The buzzer needs much voltage that microcontroller pin cannot provide, so there is a need ofan amplifier in order to be driven, a transistor can be used for this purpose. Thus the buzzeris connected in between the supply and collector of the transistor. The base of the transistoris connected to the pin of the microcontroller and for simulation purpose 5V dc source will

be used since the microcontroller also provides 5V dc on its pins.


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Figure 3.4: buzzer simulation circuit

The above circuit will be used to interface the buzzer to the microcontroller and wheneverthe pin is made high the buzzer will sound and get off when that pin is low.

The 10k resistor at the base will act as the pull up resistor for the microcontroller port andtransistor BC238BP is used. This is a low power, cheap and easily available transistor.

The buzzer specified above, have the following features:

Part Code : LGBUZZER4 Voltage: 3 - 28 Vdc

King state Buzzer - KPE-260 The operation current of 4mA at voltage of 12v Dimensions: 31mm Diameter, 13mm High, 38mm between mounting

holes

Figure 3.5: Specifications of the buzzer


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The internal resistance of the buzzer will then be (12V)/(4mA) = 3k

3.4.3 Appliance module:

Home appliances cannot be directly connected to microcontrollers; this is because they are

AC operated devices while microcontrollers are low voltage DC operated devices. Therefore

to control AC operated devices from DC voltage, a relay or a triac or a combination of relay

and triac is used depending on mechanism of controlling.

Due to availability of appliances, two bulbs which have three states ON,OFF and DIM for a

fixed low brightness will be used, the aim is to control appliances remotely and one of the

commonest appliance used at home is a bulb(240V) the states can be applied using two

relays for a single bulb and triac connections. The triacs are triggered to give varied output

AC power for the bulbs. When using a relay to control AC operated devices a relay driver is

required this is because the voltage ratings for most relays are between 6V to 24V which is

the higher than output from most microcontrollers.

Figure 3.6: Appliance interface circuit

3.4.4 Control module

This module is a brain of the system. Its main component is a microcontroller. The

microcontroller should be able of receiving data from GSM module and processes it to

produce the desired output. Furthermore it should be able of showing the status of data if

received or ready to be read. The microcontroller should have enough outputs for appliances.

To implement all these functions I chose PIC 16F876A microcontroller manufactured by

Microchip as the processing unit. The reasons for choosing the PIC are:

The availability of the programmer. It supports simple instructions defined by the MikroC compilers like MikroC

and MPLAB.

Has unused 20 pins which can be used to attach outputs for appliances. The PIC has UART interface for serial communication.[6]


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Figure 3.7: The microcontroller PIC 16F876A


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CHAPTER FOUR

4. CONCLUSION AND RECOMMENDATION

4.1 WORK DONE SO FAR

Up to now the following have been accomplished:

Literature review based on GSM and SMS technology and current existing systems. Requirement gathering (hardware and software requirements) for the control system. Requirements capture (functional) for the control system. System analysis and initial design done block by block called modules.

4.2 FUTURE WORKThe remaining task is the continuation of designing and implementation part of the system

which includes:

GSM module design. LCD module design.

Control module detail design

Software development for the required part including microcontroller.

Interfacing other modules with the control module.

4.3 CONCLUSION

This project I have undertaken has helped us gain a better perspective on various aspects

related to our course of study as well as practical knowledge of Telecommunication

Engineering. I have become familiar with problem analysis and designing steps.

The end product will have a simplistic design making it easy for users to interact with. This

will be essential because of the wide range of technical knowledge that homeowners have.

4.4 RECOMMENDATION

This project so far is a small implication of our concept in automating and monitoring a

system. The detail design and practical application are immense and can have a vast level of

implementation which will be done in the second semester of the final year. So it is not the

end of the project but rather a step towards accomplishment of the objectives. This control

system is recommended for every homes, offices, laboratories, hospitals and industries to aid


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those working or living in those places when it comes to controlling their appliances,

equipment. This control system has to be perceived by the society and the world at large as a

necessary and vital technological upgrade.

REFERENCES

1. ETimes.(2008) Home appliances [Online]. Available from: http://www.realtorindian.

com/?&action=tips&sec=General%20Information&sub=Home%20Appliances

[Accessed 22nd October 2012].

2. Shafanizam, M., Arief Y. Z. & Adzis Z. (2012) Development of electrical appliance

Controlling System using Bluetooth Technology. International Journal of

Engineering and Innovative Technology, 1(4), 1-2.

3. Sriskanthan, N., Tan, F., & Karande, A. (2002). Bluetooth based home automation system . School of Computer Engineering, Nan yang Technological University.Report number: 3.

4. Peersman,C.,Cvethovic,S.,Grif-ths,P.,Spear,H.,2000.Theglobalsystemformobilecom

municationshortmessageservice.IEEEPers.Commun. 7, 15 23.

5. Collesei,S.,Tria,P.,Morena,G.,2005.Short message service based applications in the

GSM network. In: Proceedings of Fifth IEEE International Symposium on Personal,

Indoor and Mobile Radio Communications,vol.3,pp.939 943.

6. Freescale Semiconductor.(2007).Selecting the wright Microcontroller unit[PDF-

type]. http: // www.freescale.com/files/microcontrollers/doc/app_note/AN1057.pdf


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APPENDICES:

APPENDIX A: PROJECT TIME SCHEDULE

This is the schedule activity that indicate the starting of first semester to the end of first

semester

Table 4: Project schedule for semester 1

ACTIVITY 1- Confirmation of project title and submission

ACTIVITY 2- Feasibility study and Literature Review

ACTIVITY 3- Specify requirements and specifications for the system and do analysis

ACTIVITY 4- Preliminary designing of the system

ACTIVITY 5- Progress report Submission

ACTIVITY 6- First Oral presentation

ACTIVITY 7- Compiling final report and submission

ACTIVITY 8- Final oral presentation

ACTIVITY 1

ACTIVITY 2

ACTIVITY 3

ACTIVITY 4

ACTIVITY 5

ACTIVITY 6

ACTIVITY 7

ACTIVITY 8

PROJECT SCHEDULE(SEMESTER 1)

W E E K 1

W E E K 2

W E E K 3

W E E K 4

W E E K 5

W E E K 6

W E E K 7

W E E K 8

W E E K 9

W E E K 1 0

W E E K 1 1

W E E K 1 2

W E E K 1 3

W E E K 1 4

W E E K 1 5

TIME INWEEKS

ACTIVITY


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APPENDIX B: PROJECT TIME SCHEDULE

This is the schedule activity that indicate the starting of second semester to the end of

second semester

Table 4.2: Project schedule for semester 2

ACTIVITY 1- Continuing with literature review

ACTIVITY 2- A detailed design of the system-schematic and simulations

ACTIVITY 3- Building prototype and implementation

ACTIVITY 4- Preparation and submission of progress report

ACTIVITY 5- Mid semester presentation

ACTIVITY 6- Testing and redesigning of the system

ACTIVITY 7- Compiling and submission of project final report

ACTIVITY 8- Final project presentation

ACTIVITY 1

ACTIVITY 2

ACTIVITY 3

ACTIVITY 4

ACTIVITY 5

ACTIVITY 6

ACTIVITY 7

ACTIVITY 8

PROJECT SCHEDULE(SEMESTER 2)

W E E K 1

W E E K 2

W E E K 3

W E E K 4

W E E K 5

W E E K 6

W E E K 7

W E E K 8

W E E K 9

W E E K 1 0

W E E K 1 1

W E E K 1 2

W E E K 1 3

W E E K 1 4

W E E K 1 5

TIME INWEEKS

ACTIVITY


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APPENDIX C: COST ESTIMATIONS

The following table describes the estimated costs for the project

No Component/Material Cost/Price

1. Microcontroller 30,000/=

2. GSM cellular phones/modules 120,000/=

4. Relays and Triacs 10,000/=

5. LCD 40,000/=

6. Diodes, Resistors and Capacitors 25,000/=

7. Connectors 5000/=

8. Stationary 20,000/=

9. Miscellaneous Electronic components

and other materials

20,000/=

Total 270,000/=

Table 4.2: Cost estimates for the project


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final year report 1

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