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RF600 system planning
4.6 The response of electromagnetic waves in the UHF band
This effect depends very much on the transmitted power, the components being used (cable,
antenna) and the distance from the metallic surface to the antenna. In this case,
repositioning/realigning the antenna or reducing the radiated power can remedy the
situation.
4 4 .6.3
Influence of liquids and non-metallic substances
Non-metallic substances can also affect the propagation of electromagnetic waves and thus
the transponder range.
When non-metallic substances or objects that can absorb UHF radiation are located in the
propagation field, these can alter the antenna field depending on their size and distance and
can even extinguish the field entirely.
The RF damping effect of water, materials containing water, ice and carbon is high.
Electromagnetic energy is partly reflected and absorbed.
Oil- or petroleum-based liquids have low RF damping. Electromagnetic waves penetrate
these liquids and are only slightly weakened.
4.6.4
Influence of external components
The RED guideline and the relevant standards govern the electromagnetic compatibility
requirements. This also concerns the third-party components of the RF600 system. Even
though requirements for electromagnetic compatibility are defined, various components will
still interfere with each other.
The performance of the RF600 system is highly dependent on the electromagnetic
environment of the antennas.
Reflections and interference
On the one hand, antenna fields will be weakened by absorbing materials and reflected by
conducting materials. When electromagnetic fields are reflected, the antenna field and
reflecting fields overlap (interference).
Third-party components in the same frequency band
On the other hand, third-party components may transmit on the same frequency band as the
reader, or the third-party components may transmit in different frequency bands with side
bands that overlap with the frequency band of the reader. This results in a reduction of the
"signal-to-noise" ratio which reduces the performance of an RF600 system.
If a DECT station that is transmitting in the 2 GHz band, for example, is located in the
receiving range of an antenna of the RF600 system, the performance of the write and read
access to the transponder may be reduced.
68
System Manual, 06/2019, J31069-D0171-U001-A22-7618
SIMATIC RF600
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