RFID stands for Radio Frequency IDentification. RFID is a small electronic device consist of small chip and an antenna. The chip typically is capable of carrying data.
Radio frequency identification (RFID) is a generic term 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.
RFID – Basics
RFID is something similar to a barcode, which has set of thick and thin vertical black lines, that you find on everything you buy . Barcodes are used to automatically identify an object, by using a machine known as a barcode scanner.
If every object were assigned a code number, then to manually identify each object by reading the code number and looking it up in a table or a database to see what it indicates, would be very time consuming.
The vertical lines look like bars and they stand for the code number so it was called a bar code. The bar code scanner scans such bar codes and sends scanned code number to a computer which decodes it and tells us that the object is a box of cereals, shampoo bottle depending on the code number.
RFID is something similar, except the visual pattern of thick and thin black lines. It has a data chip (containing a unique code number) and an antenna in the form of a tag, which is affixed to the object to be identified.
For a box of breakfast cereals will now have an RFID tag attached to it, instead of the printed bar code. If the box is now held near an RFID scanner, it will communicate with the RFID tag wirelessly and read its code number.
RFID – Radio frequency identification system uses tags, or labels attached to the objects to be identified. The tag’s information is stored electronically in a non-volatile memory.
The RFID tag includes a small RF transmitter and receiver. An RFID reader transmits an encoded radio signal to interrogate the tag. The tag receives the message and responds with its identification information.
This may be a unique serial number, or may be product-related information such as a stock number, lot or batch number, production date, or other specific information.
RFID tags can be either passive, active or battery assisted passive. An active tag has an on-board battery and periodically transmits its ID signal.
A battery assisted passive has a small battery on board and is activated when in the presence of a RFID reader. A passive tag is cheaper and smaller because it has no battery.
Instead, the tag uses the radio energy transmitted by the reader as its energy source. The interrogator must be close for RF field to be strong enough to transfer sufficient power to the tag.
The RFID scanner now sends this code number to a computer, which again looks it up in the database, finds that the number belongs to a box of cereals.
RFID – Components
Basic RFID system consists of three components:
1) An antenna or coil
2) A transceiver (with decoder)
3) 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 and the data is passed to the host computer for processing.
RFID – Application and Uses
The RFID tag can be affixed to an object and used to track and manage inventory, assets, people, etc. For example, it can be affixed to cars, computer equipment, books, mobile phones, etc.
Wide application of RFID includes,
- Access management
- Tracking of goods
- Tracking of persons and animals
- Toll collection and contact less payment
- Machine readable travel documents
- Airport baggage tracking logistics
- Logistics and transportation
- Yard management, shipping, freight and distribution centers
- Railroad industry
- Asset Tracking
- Supply Chain Management
- Payment Systems
- Security and Access Control.