25-08-2017, 09:32 PM
DEVELOPMENT OF A GSM BASED VEHICLE MONITORING & SECURITY SYSTEM
DEVELOPMENT OF A GSM.doc (Size: 715 KB / Downloads: 94)
Introduction
The main aim of this project is to provide security to the vehicles. The system automatically locks the vehicle as soon as it receives a predefined message from the user.
Features
• The controlling unit contains the microcontroller and the GSM modem interfaced to it. The controlling unit will be fixed to the vehicle.
• The microcontroller continuously checks whether it has received any message from the modem.
• The modem provides the communication interface. The GSM modem is a wireless modem that works with a GSM wireless network
• Whenever anyone tries to unlock or take away the vehicle, immediately a message will be sent to the user mobile.
• The user, after checking the message, can respond immediately to save his vehicle.
• The microcontroller retrieves this message from the modem by issuing certain AT and T commands to the modem.
• Thus, after receiving the message from the modem, the microcontroller automatically locks the vehicle.
• This will be done perfectly without the involvement of any human.
Theoretical chapter
Embedded Systems:
An embedded system can be defined as a computing device that does a specific focused job. Appliances such as the air-conditioner, VCD player, DVD player, printer, fax machine, mobile phone etc. are examples of embedded systems. Each of these appliances will have a processor and special hardware to meet the specific requirement of the application along with the embedded software that is executed by the processor for meeting that specific requirement. The embedded software is also called “firm ware”. The desktop/laptop computer is a general purpose computer. You can use it for a variety of applications such as playing games, word processing, accounting, software development and so on. In contrast, the software in the embedded systems is always fixed listed below:
• Embedded systems do a very specific task, they cannot be programmed to do different things. Embedded systems have very limited resources, particularly the memory. Generally, they do not have secondary storage devices such as the CDROM or the floppy disk. Embedded systems have to work against some deadlines. A specific job has to be completed within a specific time. In some embedded systems, called real-time systems, the deadlines are stringent. Missing a deadline may cause a catastrophe-loss of life or damage to property. Embedded systems are constrained for power. As many embedded systems operate through a battery, the power consumption has to be very low.
The Evolution of Mobile Telephone Systems
Cellular is one of the fastest growing and most demanding telecommunications applications. Today, it represents a continuously increasing percentage of all new telephone subscriptions around the world. Currently there are more than 45 million cellular subscribers worldwide, and nearly 50 percent of those subscribers are located in the United States.
The concept of cellular service is the use of low power transmitters where frequencies can be reused within a geographic area. The idea of cell based mobile radio service was formulated in the United States at Bell Labs in the early 1970s. Cellular systems began in the United States with the release of the advanced mobile phone service (AMPS) system in 1983. The AMPS standard was adopted by Asia, Latin America and Oceanic countries, creating the largest potential market in the world for cellular.
In the early 1980s, most mobile telephone systems were analog rather than digital, like today's newer systems. One challenge facing analog systems was the inability to handle the growing capacity needs in a cost efficient manner. As a result, digital technology was welcomed.
Microcontrollers:
Microprocessors and microcontrollers are widely used in embedded systems products. Microcontroller is a programmable device. A microcontroller has a CPU in addition to a fixed amount of RAM, ROM, I/O ports and a timer embedded all on a single chip. The fixed amount of on-chip ROM, RAM and number of I/O ports in microcontrollers makes them ideal for many applications in which cost and space are critical.
The Intel 8051 is Harvard architecture, single chip microcontroller (µC) which was developed by Intel in 1980 for use in embedded systems. It was popular in the 1980s and early 1990s, but today it has largely been superseded by a vast range of enhanced devices with 8051-compatible processor cores that are manufactured by more than 20 independent manufacturers including Atmel, Infineon Technologies and Maxim Integrated Products.
Description:
The AT89s52 is a low-voltage, high-performance CMOS 8-bit microcomputer with 8K bytes of Flash programmable memory. The device is manufactured using Atmel’s high density nonvolatile memory technology and is compatible with the industry-standard MCS-51 instruction set. The on chip flash allows the program memory to be reprogrammed in system or by a conventional non volatile memory programmer. By combining a versatile 8-bit CPU with Flash on a monolithic chip, the Atmel AT89s52 is a powerful microcomputer, which provides a highly flexible and cost-effective solution to many embedded control applications.
In addition, the AT89s52 is designed with static logic for operation down to zero frequency and supports two software selectable power saving modes. The Idle Mode stops the CPU while allowing the RAM, timer/counters, serial port and interrupt system to continue the functioning. The power-down mode saves the RAM contents but freezes the oscillator disabling all other chip functions until the next hardware reset.