Sunday, 6 September 2015

RFID MULTIMEDIA TECHNOLOGY Sem1 2015

 Radio Frequency Identification Device (RFID)


Table of contents

-Introduction

-What is RFID

-How RFID works

-Examples

-Uses inside living bodies

-RFID vs Bar-codes

-Problems with RFID

Introduction


For many of us, using a key to start a car, a card to access a building or room, using ski lifts on a winter sports holiday and validating a bus or underground ticket have become part of our daily routine. Without always realizing it, we use automatic data capture technology that relies on radio-frequency electromagnetic fields. This technology is known as Radio-Frequency IDentification or RFID. Just as people use RFID as they go about their daily lives, objects also use this technology, as they transit from manufacture to storage and finally the point of sale. Like us, they also carry RFID tags. The difference between objects and ourselves is that they don’t “voluntarily” present their RFID tag or card when asked. These tags are therefore read in very different conditions and often require greater detection distances.

RFID (Radio Frequency Identification) can be defined as follows: Automatic identification technology which uses radio-frequency electromagnetic fields to identify objects carrying tags when they come close to a reader. So what is RFID and how does it works.

-What is RFID ?


Radio Frequency Identification (RFID) technology is changing the world. This much we know: at the heart of the matter, RFID is simply the electronic bar code. An RFID system has readers and tags that communicate with each other by radio. RFID tags are so small and require so little power that they don’t even need a battery to store information and exchange data with readers. This makes easy and cheap to apply tags to all kinds of things that people would like to identify or track. RFID can tell you what an object is where it is and even its condition which is why it is integral to the development of the Internet of Things—a globally interconnected web of objects allowing the physical world itself to become an information system, automatically sensing what is happening sharing related data and responding. RFID stands for identification is a generic term that is used to describe a system that transmits the identity (in the form of a unique serial number) of an object or person wirelessly using radio waves. It's grouped under the broad category of automatic identification technologies. The acronym refers to small electronic devices that consist of a small chip and antenna. Chip usually capable of carrying 2000 bytes of data or less.




-How RFID works ?






Systems that make use of RFID technology are typically composed of three key elements:

1. An RFID tag, or transponder, that carries object-identifying data.
2. An RFID tag reader, or transceiver, that reads and writes tag data.
3. A back-end database, that stores records associated with tag content

Each tag contains a unique identity code. An RFID reader emits a low-level radio frequency magnetic field that energizes the tag. The tag responds to the reader’s query and announces its presence via radio waves, transmitting its unique identification data. This data is decoded by the reader and passed to the local application system via middleware. The middleware acts as an interface between the reader and the RFID application system. The system will then search and match the identity code with the information stored in the host database or backend system. In this way, accessibility or authorization for further processing can be granted or refused, depending on results received by the reader and processed by the database.


-Examples

1- Student Access Card
2- Mobile Phone
3- Car`s Remotes
4- Visa Card

5- Access Cards, Chips


6- Tracking Shipments





-Uses inside living bodies
 
RFID devices that are intended to be implanted inside a living body (like an animal or human being) have special requirements. They need to be encased in a special kind of casing that will not irritate or react with the living tissues that they are inserted into. The casing must also be transparent to the scanning radio-frequency beam that activates the chip. Some RFID vendors have created bio-compatible glass for use in these applications.
One potential problem with being placed within a living organism is that the tiny RFID device may move around under the skin. This can be avoided by using special materials that actually let the surrounding tissue grow up to the casing and bond with it.
Because the radio-frequency waves that activate the microchip containing the identification number are only useful within a few feet (or less), the RFID chip is typically inserted very close to the surface of the skin.
The placement of the device is usually done with a hyperdermic-type needle. This method of insertion also dictates the shape and size of the device; implantable RFID devices are typically the size and diameter of a grain of rice. For dogs, the device is usually implanted between the shoulder blades.
RFID tags have been placed inside cows; some discussion of having all cows implanted with RFID devices has resulted from the recent scare with mad cow disease. Dog owners have used RFID tags to identify their pets rather than tattoos (the more traditional method) 

On Oct-17-2004 The Food and Drug Administration (FDA) has given final approval to Applied Digital Solutions to sell their VeriChip RFID tags for implantation into patients in hospitals. The intent is to provide immediate positive identification of patients both in hospitals and in emergencies. Doctors, emergency-room personnel and ambulance crews could get immediate identification without resorting to looking for wallets and purses for ID. If, for example, you had a pre-existing medical condition or allergy, this could be taken into account immediately.
The Federal Drug Administration has approved a final review process to determine whether hospitals can use VeriChip RFID tags to identify patients. The 11-millimeter RFID tags will be implanted in the fatty tissue of the upper arm. The estimated life of the tags is twenty years. 



And some people took this to the next level by implanting the chip into their hand as a secure method to get into their houses or cars without the hassle to carry a key.







-RFID vs Bar-codes



-Problems with RFID

1- RFID systems can be easily disrupted:
Since RFID systems make use of electromagnetic spectrum like (wifi networks or cellphones),
It’s possible to jam RFID by using right radio frequency. Although this would be an inconvenience in stores, it could be disastrous in other environments like the hospitals or military facilities. 

2- RFID reader collision:
Reader collision occur when the signal from two or more reader overlap. The tag is unable to respond to simultaneous us queries. That’s why many systems use an anti collision protocol. 

3- Privacy problems:
A- RFID contents can be read by almost anyone
Unlike barcodes, the tags can be read without being scanned, anyone with RFID tag reader can read the tags embedded in your clothes, credit cards, and other consumer products.
B- RFID can be read with a greater distance antenna
For various reasons, RFID reader/tag systems are designed so that the distance between the reader and the tag is kept to the minimum. However a high gain antenna can be used to sniff/read the tag from a long distance. 

4- RFID tags signal can be blocked:
RFID tag signal can be blocked by enveloping the tag with a metal bag that will block the signal from being read by the reader. Sometimes store thieves use this method to go undetected by the RFID alarm. 

5- RFID can be difficult to remove:
RFID tags can be difficult for consumers to remove, some are very small and as thin as a piece of paper, other may be hidden or embedded inside products where consumers cannot see them. New technologies allow RFID to be printed right on a product and may not be removable at all. 





THE END























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