RFID tags

(radio frequency identification tags) are basically intelligent bar codes that can communicate with a system and can be tracked.

Main Purpose:

Identify and follow each product among thousands of them. The barcodes created in 1970s has a very slow scanning process both in factory and store. Also since they are just a piece of paper, it cannot send out any information.

Features :

Where They are Used? :

Physics Behind Them:

An example of RFID tag

rfid

RFID tags take the energy they need to work from magnetic field generated by RFID reader.

(Since a magnetic field can be created with electricity, electric current can be created with a magnetic field )

RFID tags can store up to 2 kilobytes of data and are made of a microchip, antenna and, battery for the case of active and semi-passive tags.

Data stored in RFID tag’s microchip Antenna receives electromagnetic energy to power tag’s battery Sends information inside of microchip to reader

A figure shows electromagnetic waves rfid

Sources:
http://electronics.howstuffworks.com/gadgets/high-tech-gadgets/rfid.htm
http://ieeexplore.ieee.org/xpl/tocresult.jsp?isnumber=7243394&punumber=45
Weis, Stephen A. (2007), RFID (Radio Frequency Identification): Principles and Applications, MIT CSAIL