SIMATIC RF600
System Manual, 06/2019, J31069-D0171-U001-A22-7618
359
T
Transponder
7
7
7
7.1
Overview
7.1.1
Mode of operation of transponders
The transponder mainly comprises a microchip with an integrated memory and a dipole
antenna.
The principle of operation of a passive RFID transponder is as follows:
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Diversion of some of the high-frequency energy emitted by the reader to supply power to
the integrated chip
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Receiving commands from the reader
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Responses are transmitted to the reader antenna by modulating the reflected radio waves
(backscatter technique)
Figure 7-1
Mode of operation of transponders
The transmission ranges achieved vary depending on the size of the transponder and
therefore its dipole antenna. In general the following rule applies: The smaller the
transponder and therefore the antenna, the shorter the range.