Beckhoff CU8890-0000, Installation And Operating Instructions Manual

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Operating Instructions
10 CU8890-0000
Operating Instructions
IEEE 802.11 Standard
Wireless LANs (WLANs) are local radio networks with main reference to
wireless computer networks. The IEEE 802.11 standard was first published
in 1997.
Basically the standard allows either the wireless connection of two (or
more) PCs (or laptops) with each other directly (adhoc) or to expand an
existing wired computer network with an infrastructure (access points) for
wireless users.
The most popular standard is the IEEE 802.11 b/g that provides a data
transfer rate up to 54 MBit/s for the 2.4 GHz band. The data rate is
adjusted dynamically.
The standard provides 11 channels worldwide, but only 3 can be used
without overlapping:
Channel overlapping
When using the network in a confined area (e.g. in a factory building)
notice the following comb-shaped structure with a channel difference of 5
channels to each neighbor cell:
Comb-shaped