Baumer Ident OIS-P PC 3100 series, Руководство по установке

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OIS-P, PC3141/03 Manual Baumer Ident 17
System performance
2.3 Distance between Data Tags
Narrow antenna field
The data transmission frequency of 2,45 GHz
offers many excellent characteristics, of which one
is the ability to “focus” the microwaves on a desired
area, much like a flash light throws out a narrow
beam of light.
Figure 2.4 Focussing on the “right” object thanks to the narrow antenna field.
Data Tag ID-address
To further enhance installation flexibility and ensure
optimum communication reliability, each Data Tag
has a unique identity. The so called ID-address is
factory programmed from a range of more than 16
million (2
24 ) ID-addresses. The unique ID-
addresses will ensure that communication initiated
with an Data Tag also can be finalized with the that
particular Data Tag, even if another Data Tag
would come in closer to the antenna. It is thus
important that the ID-addresses remain unique
even if the user reinitialises the tags. The system
is, however, basically designed for one tag in the
lobe and other situations should be avoided.
Distance between Data Tags
It is important that the Data Tag with which
communication is to be established, returns the
strongest signal to the antenna, as the Data Tag
communication is initiated by OD or user
command. To translate that into a minimum
distance between Data Tags, an antenna lobe
diagram must be studied.
The graph lines in figures 2.1 and 2.2 represent
positions of similar signal strength in front of an
antenna. The distance between two graph lines
represent a signal strength difference of 3 dB.