RF600
System Manual, 09/2005 Edition, J31069 D0171-U001-A0-7618,
7-1
Transponder/tags
7
7.1
Mode of operation of transponders
The tag/transponder mainly comprises a microchip with an integral memory and a dipole
antenna.
The principle of operation of a passive RFID transponder is as follows:
•
Diversion of some of the high-frequency energy emitted by the reader to supply power to
the integral chip
•
Commands received from reader
•
Responses are transmitted to the reader antenna by modulating the reflected radio
waves (backscatter technique)
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Figure 7-1
Mode of operation of transponders
The transmission ranges achieved vary in accordance with the size of the tag and the
corresponding dipole antenna. In general the following rule applies: The smaller the tag and
therefore the antenna, the shorter the range.