RADIO FREQUENCY IDENTIFICATION

RFID TECHNOLOGY DEFINITION:

Radio-frequency identification (RFID) is a technology that uses communication through the use of radio waves to exchange data between a reader and an electronic tag attached to an object, for the purpose of identification and tracking.

 PURPOSE:

The purpose of an RFID system is to enable data to be transmitted by a portable device, called a tag, which is read by an RFID reader and processed according to the needs of a particular application

The data transmitted by the tag may provide identification or location information, or specifics about the product tagged, such as price, color, date of purchase, etc.

RFID quickly gained attention because of its ability to track moving objects.

INTRODUCTION

The RFID stands for “radio frequency identification”. it is the name given to systems that put “tags” on objects(items bought and sold commercially, documents ,people ,animal, vehicles, containers ,and so on)so they can be identified, tracked, and managed automatically utilizing radio frequency equipment and supporting computer systems

 The data in the tag may be a simple identification number that identifies the object, or it may fully describe it. It may give its history or contain relevant information such as warnings and instructions

RFID is one of many tools that perform automatic collection of data. Thus, RFID can automatically gather data that might not be collected

otherwise. Having the collected data, you can then use it to improve your

operations and solve several very complex and time-sensitive problems. RFID’s basic technology dates from World War II, where it was

used to identify friendly ships and airplanes. Today, low-cost tags and equipment and sophisticated applications support a variety of new uses for technology beyond aircraft identification.

RFID systems generate data that organizations can use to improve operations. RFID’s proponents claim that these systems:

Improve management of facilities, assets and the resources.

Reduce theft or misplacement of goods, tools, equipment, files, prisoners, or small children.

Keep detailed records of the history of each item in trade. Increase the speed and accuracy of nearly all business

transactions.

Enable suppliers to comply with customer mandates.

History and background

In 1945 León Theremin invented an espionage tool for the Soviet Union which retransmitted incident radio waves with audio information.

Even though this device was a covert listening device, not an identification tag, it is considered to be a predecessor of RFID technology, because it was likewise passive, being energized and activated by waves from an outside source.

Mario Cardullo's device in 1973 was the first true ancestor of modern RFID, as it was a passive radio transponder with memory.

The original business plan presented to investors in 1969 showed uses in:

The basic Cardullo patent covers the use of RF, sound and light as transmission media:

transportation (automotive vehicle identification, automatic toll system, electronic license plate, electronic manifest, vehicle routing, vehicle performance monitoring),

banking (electronic check book, electronic credit card),

security (personnel identification, automatic gates, surveillance) and

Medical (identification, patient history).

MAJOR VENDOR SUPPORT FOR RFID:

RFID has attracted the attention of the most sophisticated companies in the technology sector

IBM, Accenture, sun, HP, Microsoft, and Intel have all announced major investments in RFID products and services.

RFID today delivers value for companies, with the ability to provide real-time error-free information that they can use to solve complex business problems

The technology will continue its rapid adoption throughout the total supply chain.

The ABCs of RFID

Understanding what RFID devices are and how they work is critical to an analysis of the policy issues surrounding this technology.

Generic references to “RFID technology” may be applied incorrectly to a wide range of devices or capabilities.

For example, RFID by itself is not a location-tracking technology. At sites where readers are installed, RFID may be used to track tagged objects, but this static readability differs from technology such as global positioning systems, or GPS, which uses a network of satellites to pinpoint the location of a receiver.

And RFID technology itself can be used for a variety of applications, from contactless identification cards that can be scanned no farther than inches away from a reader, to highway systems utilizing “active” RFID tags that can

initiate communication with a scanner 100 feet away.

COMPONENTS OF RFID SYSTEM:

The RFID system is a set of components that work together to capture, integrate, and utilize the data and information. The components of RFID system are as follow:

  Sensors Tags Antennas Connectors Cables Readers Networks Controllers Data Software Information services

Basic three components

But a basic RFID system consists of three components:

An antenna or coil A transceiver (with decoder) A transponder (RF tag) electronically

programmed with unique information.

 

The antenna emits radio signals to activate the tag and to read and write data to it.

  The reader emits radio waves in ranges of anywhere

from one inch to 100 feet or more, depending upon its power output and the radio frequency used. When an RFID tag passes through the electromagnetic zone, it detects the reader's activation signal.

The reader decodes the data encoded in the tag's integrated circuit (silicon chip) and the data is passed to the host computer for processing.

COMPONENTS

DATA: The component of the RFID system is the DATA. Several times per second, readers broadcast a signal, and

tags respond. TAGS: An RFID tag is a small device that can be attached to an item,

case, container, or pallet so it can be identified and tracked. Tags comes in variety of: Sizes Characteristics Shapes Performance Cost

Tags come in variety of formats:

Plastic cards resembling a credit card but slightly thicker, Wrist bands and wrist watches, Coins and tokens, Paper tags, including some countries currency,etc.

One way of classifying the tags is based on the means by which they transmit the messages.

These are active tags, passive tags, and semi passive tags.

three types of RFID tags

ACTIVE TAG: Active tags have a transmitter for sending

signals to the reader.

Active tags can be viewed as the miniature computers, capable of operating sensors and performing calculations and logic operations, and two-way communication over substantial distances.

Active tags can initiate communication and typically have onboard power. But it may come from other sources.

They can communicate the longest distances – 100 or more feet.

Active tags are costly as compared to the passive tags. So their use is limited to high value items and processes.

Power random access memory (RAM) giving them the ability to store up to 32,000 bytes of data.

PASSIVE TAG: Passive tags transmit only when they are

only in the field of a reader. Otherwise they are silent.

Passive tag derives their power from the signal they receive from the reader.

Passive tags have no onboard power source – meaning no battery – and do not initiate communication.

Passive tags are already used for a wide array of applications, including:

building-access cards, mass transit tickets, and, increasingly, tracking consumer

products through the supply chain

Semi-passive tags

A third category of tags has emerged, called semi passive tags, they are sometimes called semi active tags or battery-assisted tags.

› Semi-passive tags, like passive tags, do not initiate communication with readers, but they do have batteries.

This onboard power is used to operate the circuitry on the chip, storing information such as ambient temperature

There are three benefits to the semi passive tags:

the tags can be read at higher speeds than passive tags. Since they don’t need to take the time to energize their circuitry based on receiving transmission from the reader.

The ability to continually monitor the record external conditions. They may use the battery powers for various types of sensors.

Is the possibility of transmitting from the opaque materials that would inhibit the passive tag? The semi passive tag circuitry is more sensitive one.

Active tags over passive tags

THE ANTENNA: The antenna attached to the chip is responsible for transmitting

information from the chip to the reader, using radio waves. Generally, the bigger the antenna, the longer the read range. CONNECTOR:  Connectors are used to connect the cables to the readers and the

antennas. READERS:  A reader uses its antennas to stimulate the tags, read their data,

and transmit it via a network to a host computer. Readers can also commission a tag and write data to its memory.

Thus the term reader should properly be “reader/writer”. In today’s, more sophisticated cases, the reader sends

authentication information and commands coded in the radio waves

READERS PERFORMANCE consists of the following elements, which are as written below:

Identification range : The distance at which 100

percent of a tag population can be identified. Identification rate : The number

of tags that can be identified and counted per second.

Read range: The distance at which 100 percent of a tag

population can be read.

Read rate: The number of tags that can be read per second.

Write range: The distance at which unique identifiers can be

written to 100 percent of a tag population.

Write rate: The number of tags that can be written to per

second. 

CONTROLLERS:

RFID controllers are a relatively new class of hardware.

They interface between a group of readers and the computers network and provide infra- structure connectivity to the various sensors and device of complete RFID solution.

Infra-structure devices such as readers, label printers, pallet controllers, and conveyor controllers and discrete devices such as proximity switches, light towers, and alarms can be interfaced to one or more controllers, providing a common interface to the host computer system.

RFID CYCLE

RADIO FREQUENCY

Communication between RFID tags and readers is also affected by the radio frequency used, which determines the speed of communications as well as the distance from which tags can be read.

FREQUENCY RFID SYSTEMS Low frequency RFID systems. High frequency RFID systems.

Low frequency RFID systems

Low frequency RFID systems use the frequency range 125-134 KHZ.

• This corresponds to radio waves about 2300 meters long.

  Use: In RFID, these systems are mostly used

for Animal tagging Access control Immobilizers

• They are not very susceptible to the opaque materials

• The very oldest frequency in existence

• The antennas needed to work with such long waves are relatively large and relatively expensive.

• Low frequency systems are ideal when the environment contains dirt, snow or mud.

 HIGH FREQUENCY RFID SYSTEM

High-frequency (HF) RFID systems around the world use the 13.553-15.567 MHZ frequency.13.56 waves are about 22 meters long.

COST: These tags are less expensive than the low frequency tags.

TECHNOLOGY: This technology is very stable and mature. HF communication for RFID actually takes place using

magnetic coupling rather than exchange of radio-waves

USE: They are widely used in the: smart cards, access control, luggage control, biometric identification systems, Libraries, etc

RADIO FREQUENCY Low frequency RFID systems

use the frequency range 125-134 KHZ

Opaque materials: Not susceptible

Read range: 20 inches

Read rates: Slow

Application Animal tagging, access control,

vehicle mobilizes

High-frequency (HF) RFID systems around the world use the 13.553-15.567 MHZ frequency.13.56 waves are about 22 meters long

Opaque materials somewhat susceptible

Read range: 1 meter

Read rates: Faster than low frequency system.

Application: Access control, payment ID,item level tagging,

luggage control, library books, laundries

 

Low frequency RFID systems

HIGH-FREQUENCY RFID SYSTEMS:

 

Read/Write Capacity

Another important feature of RFID tags is their “read/write” capacity, or “read-only” status.

These terms refer to a tag’s ability to have data added to it during its lifetime. The information stored on a “read-only” tag cannot be altered, but a writeable tag (with read/write capacity) can receive and store additional information.

Read/write applications are most prevalent when tags are re-used. They are usually more sophisticated and costly than read-only applications.

In addition, read/write applications have shorter read ranges

USES OF RFID

In a pharmacy, a druggist can fill a prescription from a bottle bearing an RFID-chipped label confirming the authenticity of its contents.

On the highway, cars with RFID tags on their windshields can move swiftly through highway tollbooths, saving time and reducing traffic congestion.

At home, pets can be implanted with chips so that lost animals can be identified and returned to their owners more readily.

Asset Tracking It's no surprise that asset tracking is one of the most common

uses of RFID.Companies can put RFID tags on assets that are lost or stolen

often, that are underutilized or that are just hard to locate at the time they are needed

Retailing Retailers such as Best Buy, Metro, Target, Tesco and Wal-Mart are in the forefront of RFID adoption.

These retailers are currently focused on improving supply chain efficiency and making sure product is on the shelf when customers want to buy it.

DIFERRENCE BETWEEN BAR CODE AND RFID

One of the key differences between RFID and bar code technology is

RFID eliminates the need for line-of-sight reading that bar coding depends on.

RFID scanning can be done at greater distances than bar code scanning.

RFID have higher cost and the advantage of multiple data sources on the same object.

High frequency RFID systems (850 MHz to 950 MHz and 2.4 GHz to 2.5 GHz) offer transmission ranges of more than 90 feet, although wavelengths in the 2.4 GHz range are absorbed by water (the human body) and therefore has limitations.

Unlike ubiquitous UPC bar-code technology, RFID technology does not require contact or line of sight for communication. RFID data can be read through the human body, clothing and non-metallic materials.

Unlike RFID labels, barcodes can be generated and distributed electronically, e.g. via e-mail or mobile phone, for printing and/or display by the recipient. An example is airline boarding passes

Comparison of RFID and barcode

CONCLUSION

RFID offers new levels of visibility for companies that want to track physical items between locations.

In the retail supply chain, goods tagged at the point of manufacture can now be traced from the factory to the shop floor, providing a real time view of inventory for all supply chain partners.

Awareness of RFID technology and the benefits it delivers is increasing across the industry.

RFID offers the possibility to develop new products and especially services which in turn opens potential new markets for companies. Altogether, these developments will contribute to a faster productivity growth, a higher per-capita income and an increasing GDP.