RFID (radio frequency identification) is a form of wireless communication that incorporates the use of electromagnetic coupling in the radio frequency portion to uniquely identify an object
RFID or Radio Frequency Identification system consists of two main components, a transponder/tag attached to an object to be identified, and a Transceiver also known as interrogator/Reader.
A Reader consists of a Radio Frequency module and an antenna which generates high frequency electromagnetic field. On the other hand, the tag is usually a passive device, meaning it doesn’t contain a battery. Instead it contains a microchip that stores and processes information, and an antenna to receive and transmit a signal.
To read the information encoded on a tag, it is placed in close proximity to the Reader (does not need to be within direct line-of-sight of the reader). A Reader generates an electromagnetic field which causes electrons to move through the tag’s antenna and subsequently power the chip. The powered chip inside the tag then responds by sending its stored information back to the reader in the form of another radio signal. This is called backscatter. The backscatter, or change in the electromagnetic/RF wave, is detected and interpreted by the reader which then sends the data out to a computer or microcontroller.
RFID tags are categorized according to the frequency at which they are designed to operate • Low frequency (LF) -It range includes frequencies from 30 to 300 KHz.
• High frequency (HF) -It range includes frequencies from 3 to 30 MHz.
• Ultra high frequency (UHF) -It range includes frequencies from 300 to 1000 MHz.
• Microwave frequency (microwave) -It range includes frequencies from