Siemens SIMATIC RF640A, Системное руководство

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RF600 system planning
4.6 Planning and installation of UHF read points
SIMATIC RF600
68
System Manual, 11/2018, J31069-D0171-U001-A21-7618
Channel management
To operate the readers, depending on the country profile, you have between four and fifty
send channels available. Ideally, you should make the channel assignments manually in
STEP 7 Basic / Professional (TIA Portal) or in the WBM. This allows you to reduce reader-to
reader influence and if applicable field obliteration.
Table 4- 4 Example of a channel plan according to ETSI
Reader Reader 1 Reader 2 Reader 3 Reader 4 Reader 5 ...
Transmission
channel
4 10 7 13 4 ...
Frequency
(MHz)
865.7 866.9 866.3 867.5 865.7 ...
Use of multiple antennas
If you do not find the ideal antenna position to be able to identify the transponders in the
various positions and alignments, you have the option of using more antennas. Multiple
antennas mounted at different positions enlarge the identification range.
Enabling send pauses
If too many neighboring readers send at the same time, this causes overload of the radio
channels. In this case, enable the "Intermissions" function in the "Settings - General" menu
item to improve read reliability.
Varying the antenna polarization
By using linear or circular antennas, you can reduce field obliteration. This improves the
reader reliability in difficult radio conditions.
The RF685R and RF680 readers also provide the option of operating the internal or external
antenna both as a linear, vertical, linear horizontal and circular antenna. If more than one
polarization is enabled, the polarization is changed automatically with each inventory. This
increases the probability of identification in difficult radio conditions.
Changing the antenna position
In difficult radio conditions (e.g. where there is a lot of metal) it is possible that the
communication between transponders and readers is impaired. You can counter this by
changing the position of the antenna relative to the transponder. This also changes the
multipath propagation of the radio waves and obliteration is reduced or shifted.
Use of UHF algorithms
In the "Settings - Read points" menu item of the WBM, you will find various "Tools" in the
"Algorithms" area that you can use to improve the read/write reliability.