Inductive RFIDs that operate at 134.8kHz pose a possible treat in the future
to the noise floor in the 136kHz amateur band. A paper is currently being
considered internationally that would allow an increase in the modulation
sidebands, falling in the 136kHz band and elsewhere, from the RFID system.
One item of detail omitted from the papers that are being reviewed is a
precise specification of the transmit spectrum from the RFID "readers" as
the interrogators are termed. It is assumed that it is a flat spectrum
with constant spectral density.
Grateful if anyone can provide me with more detail of the system's
modulation scheme / transmit spectrum.
73 John, G3WKL
RSGB HF Committee
[email protected]
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