Siemens SIMATIC NET System Manual page 62

Basics of communication with Industrial Ethernet
1.5 Wireless LAN
Multichannel configuration
If neighboring SCALANCE W access points use the same frequency channel, this can lead
to longer response times due to collisions that may occur. If the configuration shown in the
figure is implemented as a single-channel system, computers A and B cannot communicate
at the same time with the SCALANCE W access points in their cells.
If neighboring SCALANCE W access points are set up for different frequencies, this leads to
a considerable improvement in performance. As a result, neighboring cells each have their
own medium available and the delays resulting from time-offset transmission no longer
occur.
The channel spacing should be as large as possible; a practical value is 25 MHz. Even in a
multichannel configuration, all SCALANCE W access points can be configured with the same
network name.
Figure 1-4
62
Multichannel configuration on channels 1 and 7 with four SCALANCE W access points
System Manual, 09/2019, C79000-G8976-C242-10
Industrial Ethernet