Texas Instruments 2000 series, Справочное руководство

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45
Transmitter Carrier Phase
Synchronization (CPS)
In some applications it is necessary to use several charge-up antennas close to
each other. Under these circumstances, the magnetic charge-up fields generated
by different antennas superimpose on each other and may cause a beat effect on
the magnetic charge-up field, due to the slightly different transmit frequencies of
different RA-RFMs.
The impact of this effect depends on three factors:
1. Antenna size:
The larger the size of the antennas, the further the distance between the
antennas must be, so that this effect does not occur.
2. Magnetic field strength:
The stronger the generated magnetic field strength, the further the distance
between the antennas must be such that the effect does not occur.
3. Orientation and distance between antennas:
Increasing the distance between antennas decreases the impact of this effect.
Note:
Putting two antennas close together also changes antenna
inductance, so that the antennas may no longer be tuneable to
resonance.
Appendix 4