This document describes a mini project to create an anti-theft system for vehicles using GSM. It will use an ATMEL microcontroller and Motorola GSM modem to send SMS alerts to the owner's phone if the vehicle alarm is triggered. The system will work by programming the mobile phone with AT commands to send messages via the SIM card upon detection of unauthorized access or motion. Key components include the microcontroller, GSM modem, and LCD display. Challenges included fixing short circuits during soldering and replacing damaged parts.

1. MINI PROJECT
•Anupam Singh
(0821331018)
•Vivek Kumar Gupta
(0821332038)

2. Synopsis of
GSM BASED ANTI THEFT
SYSTEM FOR VECHICLES

3. INDEX
 Introduction
 Methodology
 Objectives of anti theft system for vehicle.
 Theoretical Background
 Block Diagram & Circuit Diagram
 Component List
 List of Important AT Commands
 Programmer
 Conclusion

4. INTRODUCTION
 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 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.

5.  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.
 Main components :
microcontroller, ATMEL AT89S52
GSM modem, Motorola W220
LCD display:for simulation purpose.

6. METHODOLOGY
 The method used to carry out this project is the
principle of serial communication in collaboration
with embedded systems.
 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.

7. OBJECTIVES OF THE PROJECT
 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.

8. THEORETICAL BACKGROUND
 GSM : It 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).
 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.

9.  SIM: It 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 .

14. LIST OF IMPORTANT AT
COMMANDS
 The following are the ATCOMMAND used for programming the
GSM modem:
Example: Changing and saving parameters
 AT+IPR=9600[Enter] Transfer rate to 9600bps
 AT&W [Enter] save parameters

 AT+CMGF means convert the message to machine instruction
format
 AT+CPMS means selection of SMS memory
 AT+CMGR means read message from a given memory location
 AT+CMGD means delete message from a given memory location.

15. PROGRAMMER
 A microcontroller is a single chip
that contains the processor (the
CPU), non-volatile memory for
the program (ROM or
flash), volatile memory for input
and output (RAM), a clock and
an I/O control unit. Also called a
"computer on a chip," billions of
microcontroller units (MCUs)
are embedded each year in a
myriad of products from toys to
appliances to automobiles. For
example, a single vehicle can use
70 or more microcontrollers.

16.  The following are some of the capabilities of 8051 microcontroller.
Internal ROM and RAM
I/O ports with programmable pins
Timers and counters
Serial data communication
 The 8051 architecture consists of these specific features:
 16 bit PC &data pointer (DPTR)
 8 bit program status word (PSW)
 8 bit stack pointer (SP)
 Internal ROM 4k
 Internal RAM of 128 bytes.
 4 register banks, each containing 8 registers
 80 bits of general purpose data memory
 32 input/output pins arranged as four 8 bit ports: P0-P3
 Two 16 bit timer/counters: T0-T1
 Two external and three internal interrupt sources Oscillator and clock
circuits.

17. CONCLUSION
 Vehicles theft, which is the main concern for the conduct of this
project, is one of the biggest crimes which are hard to eliminate.
Problems encountered:
 During soldering, many of the connection become short cktd. So we
de-soldered the connection and did soldering again.
 A leg of the crystal oscillator was broken during mounting. So it has to
be replaced.
 LED`s get damaged when we switched ON the supply so we replace it
by the new one.
Troubleshooting:
 Care should be taken while soldering. There should be no shorting of
joints.
 Proper power supply should be maintained.