Antenna tuning frequency and performance

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Antenna tuning frequency and performance

M24LRXXE-R and M24SRXX-Y ICs are passive RFID memories powered by the RF

magnetic field generated by the reader. Tag to reader communication is achieved by mean

of M24SRXX-R and M24SRXX-Y impedance modulation mechanism, called load

modulation or backscattering.

Maximizing the tag operating distance requires maximizing the powering distance but also

the tag to reader link. To achieve these requirements, STMicroelectronics recommends a

tuning frequency:

•

13.56MHz and 14MHz for RFID tags based on M24LRXXE-R family,

•

14MHz and 14.4MHz for RFID tags based on M24SRXX-R family.