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Antennas
6.8 SIMATIC RF680A
SIMATIC RF600
System Manual, 11/2018, J31069-D0171-U001-A21-7618
323
6.8.6.2
Antenna patterns in the FCC frequency band
Directional radiation pattern FCC
The directional radiation pattern is shown for nominal alignment and a center frequency of
915 MHz.
Figure 6-59 Reference system
The half-power beam width of the antenna is defined by the angle between the two -3 dB
points (corresponding to half the power in relation to the maximum power). Which range (in
%) corresponds to the dB values in the patterns can be obtained from this table (Page 327).
Note that the measurements presented graphically below were carried out in a low-reflection
environment. Deviations can therefore occur in a normally reflecting environment.