Frequency Ranges
63
baby monitors, microwave ovens). Should problems with in-
terference persist despite this function, try to identify the
source of interference and switch it off manually.
Additional tips on interference in the WLAN radio network are
presented in the section
Ruling Out Interference Caused by
Other Wireless Networks from page 118
.
5-GHz frequency band
The FRITZ!Box can operate in the 5-GHz frequency band as an
alternative. This frequency range is used much less often
than the most common 2.4-GHz frequency range.
In the 5-GHz frequency band the FRITZ!Box supports automat-
ic channel switching by DFS (Dynamic Frequency Selection).
DFS ensures that the channels from 52 to 140 are kept free
for higher priority users, like weather radar systems. If you are
operating your FRITZ!Box in one of these channels, it moni-
tors the selected channel periodically for higher priority us-
ers, and, if necessary, switches to a different channel. Note
that the FRITZ!Box waits up to ten minutes, as legally re-
quired, before occupying a free channel. During this period
you cannot register any WLAN devices. The WLAN connection
is then established automatically. For more information, see
the section
Avoiding WLAN Channels with DFS on page 117
.
A prerequisite for use of the 5-GHz frequency band is that all
WLAN devices in the network support this frequency range in
accordance with the IEEE 802.11a or IEEE 8002.11n stan-
dard.
2.4 GHz or 5 GHz
The FRITZ!Box works in the wireless network either in the 2.4-
GHz range or in the 5-GHz range, but not parallel in both fre-
quency ranges at the same time.
Bandwidth
In both frequency ranges you can select between channel
bandwidths of 20 MHz or 40 MHz (exception: channel 140 in
the 5-GHz frequency band). The FRITZ!Box initially attempts
to select a channel with 40 MHz bandwidth (throughput up to
300 Mbit/s). If this is not possible due to interference or
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