Rfid

History

Radio Frequency Identification, a technology developed during the Second World War, uses radio waves to automatically identify individual items. During the war, the items were airplanes, identified through RFID as a friend or foe. Today, items can range from car parts to shampoo to livestock or even human beings. RFID is continuously automating manufacturing handle by traditional barcodes to provide tracking capabilities starting from manufacturer to retail shelves.

June 2003 was an important milestone for the adoption of RFID technology in the supply chain, as Wal-Mart issued a directive to its top 100 suppliers to put RFID tags on all pallets and cases by January 1st 2005.

The DOD (Department of Defence) followed suit with the requirement that their top 100 suppliers begin using RFID Technology by January 2005, their top 500 by July 2005 and the rest of their 43,000 suppliers by 2006.

These mandates set in motion an overall trend in advanced automation in using RFID in logistics and supply chain.

What is RFID?

RFID (Radio Frequency IDentification) is a wireless system used to identify tags. These tags may be carried by people or animals or mounted on object or vehicles. They may even be embedded under the skin.

Radio frequency identification (RFID) is basically a form of labeling where electronic labels (or “tags”) are programmed with unique information and attached to objects that need to be identified or tracked, such as pallets, vehicles, automated guided vehicles, animals, etc. The tag broadcasts its identity when it passes within range of a reader, allowing its presence to be recorded.

RFID tags are non-contact and non-line-of-sight. This means that you don't have to "swipe" your card for an RFID System to identify you.

Radio Frequency Identification (RFID) uses transponders usually called tags that have an antenna and an ASIC (Application Specific Integrated Circuit) with memory.

How does an RFID System work?

RFID uses radio waves to communicate information from a �Tag’ to a �Reader’ via an �Antenna’. The tag can be described as a small radio transmitter. Using the reader (an electronic device that communicates with the tag) and antenna it is possible to read data stored on the tag. The data can consist of serial numbers, security and/or product codes. When the reader has read the tag the information is then passed on to a host system.

The RFID tag is made up of a micro-chip with a flexible antenna. The reader emits a radio wave to scan the microchip via the antenna. When the RFID tag gets in the range of a reader, tag reflects the information that’s programmed into its memory. The tag can be read by the reader from a distance without physical contact or line-of-sight. The distance from which a reader can reliably communicate with a tag is called the read range.

The Components of an RFID System:

There Are Generally Three Components To Any RFID System

The Tag вЂ" Passive, Active, Read Only and Read Write versions programmed with a unique identifier or programmed data from the host system

The Reader/Decoder вЂ" This is used to generate the RF signal, read the data and interface to the host system

The Antenna вЂ" The point at which the RF field is generated to read the tag, this is often remote to the main decoder

RFID is used in many sectors of industry and for many uses such as:-

1. Asset Management

2. Machine and Vehicle Safety

3. Production Line Tracking

4. Logistics Tracking

5. Conveyor Tracking

6. Automotive Engine Tracking

7. Key Tagging

Passive RFID vs. Active RFID

Passive RFID tags operate using power from the RFID transceiver. Passive tags do not require a battery. Just as old-fashioned crystal radios worked from the energy of the broadcast signal, the tag is powered by the energy radiated by a reader. The "microchip" used to identify pets is a passive RFID tag. Passive tags are small and inexpensive, but do not have good range.

Active RFID tags are powered, usually by a battery. Active tags are larger and more expensive, but offer a much better identification range. The e-Tag used on toll-ways is a well-known example. The main benefit is that they have a greater range.

Passive tags are Read-Only; Active tags are typically re-write able.

RFID tags store data, which is typically used for authentication. Passive tags typically store between 32 and 128 bits of data; Active tags can store up to 1MB of data.

Tags, Inlays and Labels

RFID tags can be placed in a plastic inlay and embedded in a shipping label. In supply chain application, the label is printed and placed onto each case or pallet to be shipped. The common term for the shipping label with tag is called a “smart label”.

Benefits of a Smart Label

• Can carry traditional barcodes information together with electronic data in the same label. Should one aspect of the system goes down, product movement can still continue to use.

• Offer unattended processing capabilities

• Can be produced easily by RFID printers for on-demand applications or pre-printed and pre-coded for batch processing.

• Requires no line-of-sight placements for the reader to collect their data.

• Unaffected by heat, dust, humidity or other harsh environmental conditions.

Readers

Readers work with tags to transmit or receive data. They can be portable devices or fixed terminals that are positioned at key locations within a facility such as entrances, dock-doors, forklifts, conveyors or assembly lines.

Reader

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