Siemens CP 1515 - Manual (Page 149)

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Industrial Ethernet Wireless LAN RLM Manager, CP 1515 Manager
C79000-G8976-C171-01
149
• Considering the fact that you have added more Access Points RLMs, the
deferral behavior does no longer need to be as strict in environments
where the density of installed Radio Link Modules was fairly low:
— The stations will only defer transmissions when the signal level of a
message sensed on the wireless medium equals or exceeds a
specific level.
— Messages with a low signal level are not likely to be addressed at
the Access Point RLM that services the local cell, since the more
active roaming behavior should have caused the station to connect
to another RLM.
To support the more active roaming behavior of the wireless stations and to
compensate the lower receiver sensitivity, changing the Distance between
APs parameter should correspond with the actual increase of and more
dense placement of your Access Points RLMs.
The examples listed on the following pages will illustrate the effect of the
various Distance between APs configurations.
In Figure 30 Large Distance between APs you see the standard
configuration of networks, where
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parameter has
been set to /DUJH .
• The receiver sensitivity in this mode causes the wireless radio device to
defer transmissions for all messages that it senses within its range
(identified by the colored circles).
• Roaming stations in a specific cell will remain connected to the servicing
Access Point RLM until they exit the wireless cell.