Texas Instruments 2000 LF Series, Примечание к применению

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2.3 116 µH Inductance Antenna
The RFM-003B module requires an antenna with a self inductance of 116 µH and the
following antenna is available:
Figure 3. Mini-RFM Antenna (116 µH)
Historically, the Mini-RF Module was intended for hand-held readers and so the
antenna is supplied with a 100 mm (5”) tails.
3 Fine Tuning Antennas.
The antenna and feed cable are all part of an LC antenna matching circuit on Series
2000 readers. Changing any part has an impact on the total system, e.g. lengthening
the feeder cable. Each module requires antennas of a certain Inductance to ensure
the matching circuit is correct and, because of manufacturing tolerances, each
antenna must be fine tuned in its final positions before a system is commissioned,.
Each module has provision for this tuning.
3.1 Tuning to Resonance @ 134.2 kHz
Texas Instrument’s LF RFID system operates at 134.2 kHz and any antenna must be
fine-tuned to resonate at that frequency for optimum performance.
ƒ
(134.2 kHz)
=
1
2
π
LC
[1]
RI-ANT-P02A