Velleman K8019 Manual - page 16
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An RFID tag sleeps in normal mode: it does not perform any activities and does not use any power.
This will change as soon as the tag moves through the reader’s fi eld. An RFID reader emits radio
waves at a frequency similar to those of the tag. The tag antenna retrieves enough energy
from these waves so as to exit the tag from the sleep mode and to power the microchip.
The tag’s microchip initiates a wireless communication with the reader (comparable to
what happens with a classic network) and receives a command. The chip will execute the
command, resulting in a data transfer through the tag’s antenna. In case of the passive tag in
the example, the data consists of the unique serial number of the tag in binary format (1’s and 0’s)
emitted as radio waves.
The antenna will pick up the data emission and sends it through a cable and in the form of electrical
signals to the reader’s control module. The module will in turn decode the radio signals and retrieve
the binary data. The reader now has the tag’s ID in digital format, which can be processed or printed
immediately. This data will mostly be completed with additional data (e.g. time and location) and
quickly forwarded to a processing unit or information system.
VIII. HOW DOES AN RFID WORK?
CHIP with EPC code.
EPS, a set of numbers unique to the TAG.
ex. 0000131000756923
Important: The tag’s chip has a unique
number, i.e. the chip’s serial number
allocated during its manufacturing.