1. GSM ANTI THEFT SYSTEM FOR VECHICLES
GSM BASED ANTI THEFT SYSTEM FOR
VECHICLES
DSF
DC Motor Control
8
DC Motor Control
0
SMS
PORT1
5
1
8051
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2. TABLE OF CONTENTS
1.1 Introduction
1.2 Methodology
1.3 Scope of Work
1.4 Aims of the GSM ANTI THEFT SYSTEM FOR VECHICLES
1.5 Objectives of the GSM ANTI THEFT SYSTEM FOR VECHICLES
2.0 Theoretical Background
2.1 GSM Architecture
2.2 GSM Frequencies
2.3 Network Structure
2.4 Subscriber Identity Module (SIM)
2.5 Literature Review
2.6 GSM Security
2.7 Circuit Diagram of the GSM ANTI THEFT SYSTEM FOR VECHICLES
3.1 GSM Modem
3.1.1 Accessing GSM MODEM using Microsoft HyperTerminal
3.2 Testing of GSM Modem
3.3 List of Important AT Commands
3.4 Microcontroller – MODEM Interfacing
3.4.1. DTE and DCE
3.4.2. RS-232
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3. 3.4.3. RTS/CTS Handshaking
3.4.4. Specifying Baud Rate, Parity & Stop bits
3.4.5 DCE Baud Rates
4.1 Initializations
4.1.1 Serial transfer using TI and RI flags
4.1.2 Validity Check
4.1.3 Display
4.2 Components List
5.1 Conclusion
5.2 Problems Encountered
5.3 Future Improvement
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4. 1.1 Introduction:
In the present growing economy of India, the country also faces the uprising of crime Rate.
The offense has generated losses in properties, valuables and money and many Solutions are
performed to minimize and to prevent the crime. Vehicles theft, which is the main concern
for the conduct of this project, is one of the biggest crimes which are hard to eliminate.
The latest trend of Vehicles Theft involves the vehicles being towed away, and also alarm
signal capturing where the alarm disabler signal can be traced and duplicate by a thief with
the device to capture the signal and use it to disable the alarm. There are many alternatives to
prevent the vehicles theft, common vehicles alarm system which nearly all cars have the
system installed, and also Global Positioning System (GPS) where the whereabouts of the
vehicle scan be traced. Other alternatives include steering and gear lock, tire lock, hidden
“kill” switches which incapacitate fuel flow and many others.
The project and research is conducted for additional features in vehicles alarm system. The
device can be added to the present vehicles alarm system without any major modification to
it. When the vehicles alarm is triggered, through forced entry or motion sensor detection, the
in-vehicles phone will send SMS message to the owner’s mobile phone to alert him or her to
check the vehicle. Usually, vehicles owner realizes that their vehicles has been stolen long
after the incident, which the vehicles thief probably gotten away, and disables all the security
features in the car, or cannibalized the vehicles for spare parts and expensive items. This
happens when the owner is far away from the vehicle to hear the alarm. The SMS message
gives immediate alert to the vehicles owner, even if the thief gotten away with the car, so that
the owner can immediately take instant actions to notify the local police department or
contact the vehicles immobilizer service which come with most GPS car system to
immobilize the vehicle.
The main components of the toolkit include microcontroller, GSM modem. These
components are integrated with the device board and thus incorporate the wireless features.
The GSM modem sends the SMS. The AT commands are serially transferred to the modem.
In return the modem transmits the stored message through the wireless link. The
microcontroller used in this case is ATMEL AT89S52 .Motorola W220 is used as the GSM
modem. In this prototype model, LCD display is used for simulation purpose. The results
presented in the thesis support the proper functionalities and working of the system. The
timing diagram suggests the response of the modem to various AT (attention) commands.
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5. 1.2 Methodology:
The method used to carry out this project is the principle of serial communication in
collaboration with embedded systems. This is a very good project for Industries. This project
has a GSM ANTI THEFT SYSTEM FOR VECHICLES, which will be used as the electronic
device, and also a GSM modem, which is the latest technology used for communication
between the mobile and the embedded devices.
System will work like when the user wants to send a sms on the mishaps like someone
try to open the door of the vehicles, gas leakage at your houses and offices; the modem sent a
message through the subscriber identity module (SIM) which is inserted in the display system
MODEM.
1.3 Scope of Work
I will use liquid crystal display for displaying the message; I will also use GSM modem
(Motorola W220) as an interface between mobile and microcontroller. It will send message to
any phone irrespective of the GSM network through the modem connected to the
programmable device.
1.4 Aims of the GSM ANTI THEFT SYSTEM FOR VECHICLES
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6.  Uses: This is very useful and innovative project. We can use this to secure our offices
and houses to save our property from mishaps.
1.5 Objectives of the ANTI THEFT SYSTEM FOR VECHICLES
 Programming of the mobile phone with AT (Attention) command sequence
 Interfacing the programming chip with the personal computer
 Interfacing the programmable chip with the Buzzer and Sensors.
 Interfacing of the mobile phone with the programmable chip
 Sending messages from the remote phone to control device.
2.0 Theoretical Background
GSM (Global System for Mobile communications: originally from GROUPE Special
Mobile) is the most popular standard for mobile phones in the world. Its promoter, the GSM
Association, estimates that 80% of the global mobile market uses the standard. GSM is used
by over 3 billion people across more than 212 countries and territories . Its ubiquity makes
international roaming very common between mobile phone operators enabling subscribers to
use their phones in many parts of the world. GSM differs from its predecessors in that both
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7. signaling and speech channels are digital, and thus is considered a second generation (2G)
mobile phone system . This has also meant that data communication was easy to build into
the system.
2.1 GSM Architecture:
GSM is a complex system and difficult to understand. The Mobile Station (MS) refers to the
mobile equipment . The Base Station Subsystem controls the radio link with the Mobile
Station. The Network Subsystem performs main functions such as switching of calls between
mobile users, mobility management operations, and proper operation and setup of a network .
These functions are controlled by the Mobile Services Switching Center (MSC).
2.4 GSM Frequencies:
GSM networks operate in a number of different frequency ranges (separated into GSM
frequency ranges for 2G and UMTS frequency bands for 3G). Most 2G GSM networks
operate in the 900 MHz or 1800 MHz bands. Some countries in the Americas (including
Canada and the United States) use the 850 MHz and 1900 MHz bands because the 900 and
1800 MHz frequency bands were already allocated. Most 3G GSM networks in Europe
operate in the 2100 MHz frequency band .
2.5 Network Structure:
The network behind the GSM seen by the customer is large and complicated in order to
provide all of the services which are required.
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8. • The Base Station Subsystem (the base stations and their controllers).
• The Network and Switching Subsystem (the part of the network most similar to a
fixed network). This is sometimes also just called the core network.
• The GPRS Core Network (the optional part which allows packet based Internet
connections).
• All of the elements in the system combine to produce many GSM services such as
voice calls and SMS.
2.6 Subscriber Identity Module (SIM):
One of the key features of GSM is the Subscriber Identity Module, commonly known
as a SIM card. The SIM is a detachable smart card containing the user's subscription
information and phone book. This allows the user to retain his or her information after
switching handsets [10]. Alternatively, the user can also change operators while retaining the
handset simply by changing the SIM. Some operators will block this by allowing the phone to
use only a single SIM, or only a SIM issued by them; this practice is known as SIM locking,
and is illegal in some countries .
2.7 Literature Review:
This project is an implementation to the idea of the wireless communication between
a mobile phone and a microcontroller. Currently the main work that has been done on this
proposed system is through serial port to the computer but not wireless. If they want to
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9. control the ANTI THEFT SYSTEM FOR VECHICLES design, the systems need not be
reprogrammed to control ANTI THEFT SYSTEM FOR VECHICLES changing the
programming of microcontroller. The device will send SMS to the owner mobile number, if
the security of the vehicle in danger.
2.8 GSM Security:
GSM was designed with a moderate level of security. The system was designed to
authenticate the subscriber using a pre-shared key and challenge-response. Communications
between the subscriber and the base station can be encrypted.
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10. Fig. 2.2 Block Diagram
As we see in the above figure, there are at least three interfacing circuits, MAX-232
with Microcontroller, LCD display with microcontroller, and MAX-232 with GSM
MODEM.
2.9 Circuit Diagram of the GSM ANTI THEFT SYSTEM FOR
VECHICLES:
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11. POWER SUPPLY:
Power supply is a reference to a source of electrical power. A device or system that
supplies electrical or other types of energy to an output load or group of loads is called a
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12. power supply unit or PSU. The term is most commonly applied to electrical energy
supplies, less often to mechanical ones, and rarely to others.
Here in our application we need a 5v DC power supply for all electronics involved in the
project. This requires step down transformer, rectifier, voltage regulator, and filter circuit
for generation of 5v DC power. Here a brief description of all the components is given as
follows:
TRANSFORMER:
A transformer is a device that transfers electrical energy from one circuit to another through
inductively coupled conductors — the transformer's coils or "windings". Except for air-core
transformers, the conductors are commonly wound around a single iron-rich core, or around
separate but magnetically-coupled cores. A varying current in the first or "primary" winding
creates a varying magnetic field in the core (or cores) of the transformer. This varying
magnetic field induces a varying electromotive force (EMF) or "voltage" in the "secondary"
winding. This effect is called mutual induction.
If a load is connected to the secondary circuit, electric charge will flow in the secondary
winding of the transformer and transfer energy from the primary circuit to the load connected
in the secondary circuit.
The secondary induced voltage VS, of an ideal transformer, is scaled from the primary VP by a
factor equal to the ratio of the number of turns of wire in their respective windings:
By appropriate selection of the numbers of turns, a transformer thus allows an alternating
voltage to be stepped up — by making NS more than NP — or stepped down, by making it.
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13. BASIC PARTS OF A TRANSFORMER:
In its most basic form a transformer consists of:
• A primary coil or winding.
• A secondary coil or winding.
• A core that supports the coils or windings.
Refer to the transformer circuit in figure as you read the following explanation: The primary
winding is connected to a 60-hertz ac voltage source. The magnetic field (flux) builds up
(expands) and collapses (contracts) about the primary winding. The expanding and
contracting magnetic field around the primary winding cuts the secondary winding and
induces an alternating voltage into the winding. This voltage causes alternating current to
flow through the load. The voltage may be stepped up or down depending on the design of
the primary and secondary windings.
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REGULATOR IC (78XX):
It is a three pin IC used as a voltage regulator. It converts unregulated DC current into
regulated DC current.
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