RADIO FREQUENCY IDENTIFICATION
INTRODUCTION
Definition :-
RFID is a convenient and popular term for a technology with vague boundaries and many facets. Radio-frequency identification is not always based on radio-frequency communications and identification is only one among the many functions RFID technology can perform. Rather, RFID enables data collection with contactless electronic tags and wireless transmitters (readers) for identification and other purposes.
Concept :-
RFID uses a semiconductor (micro-chip) in a tag or label to transmit stored data when the tag or label is exposed to radio waves of the correct frequency
HISTORY
Radio frequency identification has been around for decades. Learn how it evolved from its roots in World War II radar systems to today's hottest supply chain technology.It’s generally said that the roots of radio frequency identification technology can be traced back to World War II. The Germans, Japanese, Americans and British were all using radar—which had been discovered in 1935 by Scottish physicist Sir Robert Alexander Watson-Watt—to warn of approaching planes while they were still miles away. The problem was there was no way to identify which planes belonged to the enemy and which were a country’s own pilots returning from a mission.
The Germans discovered that if pilots rolled their planes as they returned to base, it would change the radio signal reflected back. This crude method alerted the radar crew on the ground that these were German planes and not Allied aircraft (this is, essentially, the first passive RFID system).
COMPONENTS OF RFID SYSTEM
THE TAG
There are two main components present in the RFID tag. Firstly, a small silicon chip or integrated circuit which contains a unique identification number (ID). Secondly, an antenna that can send and receive radio waves. These two components can be tiny: the antenna consists of a flat, metallic conductive coil rather than a protruding FM-style aerial (see figure 1), and the chip is potentially less than half a millimetre (Hitachi, 2006).These tags can be quite small, thin and, increasingly, easily embedded within packaging, plastic cards, tickets, clothing labels, pallets and books. There are two main types of tags: passive and active. RFID Tag is a transponder which receives a radio signal and in response to it, sends out a radio signal. Tag contains an antenna, and a small chip that stores a small amount of data. Tag memory can be factory or field programmed, partition able, and optionally permanently locked.
TYPES OF TAG
Active Tags :-
Active RFID Tags are powered by an internal battery and are typically read/write, i.e., Tag data can be rewritten and/or modified. An Active Tag's memory size varies according to application requirements; some systems operate with up to 1MB of memory. In a typical read/write RFID work-in-process system, a Tag might give a machine a set of instructions, and the machine would then report its performance to the Tag. The battery-supplied power of an Active Tag generally gives it a longer read range. The trade off is greater size, greater cost, and a limited operational life .
Passive Tags :-
Passive RFID Tags operate without a separate external power source and obtain operating power generated from the reader. Passive Tags are consequently much lighter than Active Tags, less expensive, and offer a virtually unlimited operational lifetime. The trade off is that they have shorter read ranges than Active Tags and require a higher-powered reader. Read-only Tags are typically passive and are programmed with a unique set of data (usually 32 to 128 bits) that cannot be modified. Read- only Tags most often operate as a license plate into a database, in the same way as linear barcodes reference a database containing modifiable product-specific information.
THE READER
The reader is a handheld or fixed unit that can interrogate nearby RFID tags and obtain their ID numbers using radio frequency (RF) communication (i.e. the process does not require contact). When a passive tag is within range of a reader, the tag’s antenna absorbs the energy being emitted from the reader, directs the energy to ‘fire up’ the integrated circuit on the tag, which then uses the energy to beam back the ID number and any other associated information. There are two main classes of RFID readers: read-only, an example being those that operate with the purely passive EPC Class 1 tags, and read/write, which can write new information back to a tag that has been equipped with a read/write memory.
The readers are becoming increasingly sophisticated, acting as gateways into the network-centric communication systems of modern enterprises by supporting communication protocols such as TCP/IP and network technologies such as DHCP, UDP/IP and Ethernet or 802.11x (for wirelessly sending data back to the enterprise). Many models of reader are handheld devices and resemble the pricing guns or barcode scanners used in supermarkets, but readers can also be fixed in place (e.g. in doorways or at vehicle toll gateways) and even hidden, e.g. embedded into ceilings or walls.
There are also readers that can be incorporated into handheld devices such as PDAs and mobile phones (e.g. Nokia 5140, Nokia 3220 – see figure 2) and, in addition, class 5 tags are also known as 'reader' tags–devices that can read other RFID tags and exchange data with them
FREQUENCIES USED
ADVANTAGES AND DISADVANTAGES
ADVANTAGES :-
RFID tags are very simple to install/inject inside the body of animals, thus helping to keep a track on them. This is useful in animal husbandry and on poultry farms. The installed RFID tags give information about the age, vaccinations and health of the animals.
RFID technology is better than bar codes as it cannot be easily replicated and therefore, it increases the security of the product.
Supply chain management forms the major part of retail business and RFID systems play a key role by managing updates of stocks, transportation and logistics of the product.
Bar-code scanners have repeatedly failed in providing security to gems and jeweleries in shops. But nowadays, RFID tags are placed inside jewelry items and an alarm is installed at the exit doors.
The RFID tags can store data up to 2 KB whereas, the bar code has the ability to read just 10-12 digits.
DISADVANTAGES :-
The RFID technology, though very beneficial, is expensive to install. Small and medium scale enterprises find it costly to use it in their firms and offices.
It is difficult for an RFID reader to read the information in case of RFID tags installed in liquids and metal products. The problem is that the liquid and metal surfaces tend to reflect the radio waves, which makes the tags unreadable. The tags have to be placed in various alignments and angles for taking proper reading. This is a tedious task when the work involves big firms.
Interference has been observed if devices such as forklifts and walkie-talkies are in the vicinity of the distribution centers. The presence of mobile phone towers has been found to interfere with RFID radio waves. Wal-Mart, the retail sector giant, has installed billions of RFID tags in their products throughout the world and they have encountered such problems.
RFID technology has been referred to as invasive technology. Consumers are apprehensive about their privacy when they purchase products with RFID tags. Once the radio chips are installed in the product, the customer can be tracked and his personal information can be collected by the RFID reader. However, many stores have a facility that deactivates the RFID tags after the product has been purchased.
APPLICATIONS
Asset Tracking: Static or in-motion assets tracking or locating, like a healthcare facility, wheelchairs or IV pumps in, laptops in a corporation and servers in a data center, was not so easy task.User can instantly determine the general location of tagged assets anywhere within the facility with the help of active RFID technology.
People Tracking:People tracking system are used just as asset tracking system. Hospitals and jails are most general tracking required places.Hospital uses RFID tags for tracking their special patients. In emergency patient and other essential equipment can easily track. It will be mainly very useful in mental care hospitals where doctors can track each and every activity of the patient.
Document tracking:This is most common problem. Availability of large amount of data and documents brings lots of problem in document management system.
Government Library:Many government libraries use barcode and electromagnetic strips to track various assets. RFID technology uses for reading these barcodes unlike the self-barcode reader RFID powered barcode reader can read multiple items simultaneously.
FUTURE SCOPE
Many people in the industry are of the opinion that RFID is the frontrunner technology for automatic data collection and identification. One of the main benefits, which is still unproven, would be in the supply chain of consumer goods, wherein an RFID tag attached to a product would enable it to be tracked right from the point of manufacture to the retail store and then to a customer’s home.
In fact, the RFID software market is poised for taking off in a big way.
Many people in the field think that RFID technology is still in its infancy with its potential still untapped. While there is speculation about the amazingly varied ways this technology can be used, unless there are more standards put in place within the industry and until there is a reduction in the cost of RFID technology, it is unlikely that this technology will reach its full potential in the near future.
CONCLUSION
RFID technology can be the next tool for success and management of various businesses. With more research, the flaws and limitations of this technology can be removed. This will make RFID technology very useful for diverse sectors like retail, transport and jewelry businesses.
Author : Miss.Sampada
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