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INTRODUCTION1.1 OBJECTIVE OF THE WORKTo provide people with a comfortable and convenient living environment, smart home has become an important research issue. Automatic and intelligent technologies are applied to the home environment to improve the quality of life. This reminding mechanism for the user in a smart home environment. We focus on objects that the user would bring along when he/she goes out. The RFID technology is used to sense the objects the user brings along at the front door. In the object database, an object is recorded not only by its name along with a unique RFID number, but also its class. When the user leaves home, the reminder system checks the objects in his/her bags and pockets, and compares the objects with a list of objects generated by the system according to the date of the week and the events on the calendar. The system then sends a reminder object list to the user by using speaker. The background setting of this system is in a general home environment. An RFID reader is installed near the front door and RFID tags are attached to the objects the user would take out. Whenever the user goes out, the objects he/she brings along with are detected by the reader and saved in the database. We are using GSM for alerting the user by sending message or calling them. We are using like fire sensor, gas sensor, smoke sensor, IR transmitter and receiver, LDR which contributes in making a complete smart home.

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1.2 BLOCK DIAGRAM

Fig 1.1 Block Diagram

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INTRODUCTION TO EMBEDDED SYSTEMSAn embedded system is a special-purpose system in which the computer is completely encapsulated by or dedicated to the device or system it controls. Unlike a general-purpose computer, such as a personal computer, an embedded system performs one or a few pre-defined tasks, usually with very specific requirements. Since the system is dedicated to specific tasks, design engineers can optimize it, reducing the size and cost of the product. Embedded systems are often mass-produced, benefiting from economies of scale. Personal digital assistants (PDAs) or handheld computers are generally considered embedded devices because of the nature of their hardware design, even though they are more expandable in software terms. This line of definition continues to blur as devices expand. Physically, embedded systems range from portable devices such as digital watches and MP3 players, to large stationary installations like traffic lights, factory controllers, or the systems controlling nuclear power plants. In terms of complexity embedded systems can range from very simple with a single microcontroller chip, to very complex with multiple units, peripherals and networks mounted inside a large chassis or enclosure.

2.1 EXAMPLES OF EMBEDDED SYSTEMS1 .Automatic teller machines (ATMs) 2. Cellular telephones and telephone switches 3. Engine controllers and antilock brake controllers for automobiles 4. Handheld calculators, Handheld computers 5. Medical equipment 6. Personal digital assistant, Videogame consoles 7. Computer peripherals such as routers and printers 8. Industrial controllers for remote machine operation.

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RF-ID3.1 INTRODUCTION TO RF-IDRadio Frequency Identification (RFID) is a general term that is used to describe a system that transmits the identity (in the form of a unique serial number) of an object wirelessly, using radio waves. RFID is evolving as a major technology enabler for tracking goods and assets around the world. A great deal of attention is being paid to RFID by the IT industry, media and analysts. According to studies by Benchmark Research, in 2004 three quarters of manufacturing companies are now aware of RFID, of which a third are already using, piloting or investigating RFID applications for their organizations.

Fig 3.1 Radio Frequency Identification (RFID) Circuit Anticipating the potential benefits of RFID, many of the worlds major retailers are trialing RFID tagging for pallets and cases shipped into and out of their distribution centres. The consequence of this RFID activity in the retail sector is likely to impact on around 200,000 manufacturers and suppliers globally, and will fuel the market for hardware and software to support RFID. RFID has many applications outside of the retail supply chain including many familiar ones such as vehicle security, commuter tags and security badges for access control into buildings.

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3.2 THE DEVELOPMENT OF RFIDOver the years methods for capturing and storing information have evolved from paper and card systems, through keyboard data entry, bar code data capture and are now augmented by technological improvements such as touch screens on the shop floor. All of these initiatives have been aimed at improving accuracy, completeness and timeliness of information. However these all rely on access to a host computer system to make use of data collected. So, how does RFID differ from other methods of identification and data capture? A typical RFID system is made up of three components: tags, readers and the host computer system.

3.2.1 TAGS An RFID tag is a tiny radio device that is also referred to as a transponder, smart tag, smart label or radio barcode. The tag comprises a simple silicon microchip (typically less than half a millimeter in size) attached to a small flat aerial and mounted on a substrate. The whole device can then be encapsulated in different materials (such as plastic) dependent upon its intended usage. The finished tag can be attached to an object, typically an item, box or pallet and read remotely to ascertain its identity, position or state.

3.2.2 READERS The reader, sometimes called an interrogator or scanner, sends and receives RF data to and from the tag via antennae. A reader may have multiple antennae that are responsible for sending and receiving radio waves. The readers can be fixed or mobile, can read information stored on the tags and write information to them. This can be achieved without direct line of sight and in environments where traditional data collection could not operate. A major advantage is that information can be written to the tag multiple times so storing a history that travels with the article.

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3.2.3 HOST COMPUTER The data acquired by the readers is then passed to a host computer, which may run specialist RFID software or middleware to filter the data and route it to the correct application, to be processed into useful information. RFID is not a new technology, in fact it was first used by the US military during WWII, but wider deployment chain was slow due to the high costs of equipment and its limited reliability in volume environments. RFID equipment has steadily fallen in price as volumes increase and microchip unit production costs fall. With the ability to store several kilobytes of data in addition to the number plate identifier it could be viewed as a form of mass distributed database that has the potential to become ubiquitous - billions of tags in daily use throughout the world on all objects that are produced, stored, moved, sold and maintained.

3.3 AUTOMATIC IDENTIFICATIONRFID technologies are grouped under the more generic Automatic Identification (Auto-ID) technologies. Examples of other Auto-ID technologies include Smartcards and Barcodes. RFID is often positioned as next generation barcoding because of its obvious advantages over barcodes. However, in many environments it is likely to co-exist with the barcode for a long time. The barcode labels that triggered a revolution in identification systems back in the 1970s are now cheap and commonly used, but have several limitations: Low storage capacity 1. They only represent a family of items and not an individual or unique item durability (as mostly printed paper) 2. Low read range 3. They can only be read when line of sight is established 4. They can only be read one at a time 5. They cannot be written to or reprogrammed

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3.4WHAT IS RFID AND HOW WILL IT HELP YOU?Radio Frequency Identification (RFID) is a silicon chip-based transponder that communicates via radio waves. RFID has been commercially available for many years, but the latest RFID developments now offer the compatibility with an express logistics and transport system to enable the following potential improvements to service: 1. Increased security of your package and items within your shipment. 2. Visibility of items within your shipment without opening the package 3. Later cut-offs due to automated and simultaneous identification 4. Near real time track and trace, which is dynamic, automated and proactiv through links to GPS (global positioning system) and communications systems 5. Condition monitoring (eg, temperature, vibration, humidity) through links to micro sensors 6. Counterfeit protection through validation of genuine goods throughout the logistics process - Intellectual Property Rights (IPR).

3.5 WHY RFID TECHNOLOGY?Identification processes that rely on AIDC technologies are significantly more reliable and less expensive than that are not automated. RFID represents a technological advancement in AIDC because it offers advantages that are not available in other AIDC systems such as bar codes. RFID offers these advantages because it relies on radio frequencies to transmit information rather than light, which is required for optical AIDC technologies. RFID products often support other features that bar codes and other AIDC technologies do not have, Without optical line of sight, because radio waves can penetrate many materials, At greater speeds, because many tags can be read quickly, whereas optical technology often requires time to manually reposition objects to make their bar codes visible, and Over greater distances, because many radio technologies can transmit and receive signals more effectively than optical technology under most operat