Frequency Ranges
FRITZ!Box Fon WLAN 7570 vDSL
131
In the 5-GHz frequency band, your FRITZ!Box occasionally
may change channels unexpectedly due to DFS (Dynamic
Frequency Selection) if a “higher privileged user” simulta-
neously claims the selected channel. This can happen es-
pecially when military or civilian radar is used in the imme-
diate vicinity.
A prerequisite for use of the 5-GHz frequency band is that
all WLAN adapters in the network support this frequency
range in accordance with the IEEE 802.11a or IEEE 8002.11n
standard.
2.4 GHz or 5 GHz
The FRITZ!Box works in the WLAN 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 at-
tempts to select a channel with 40 MHz bandwidth
(throughput up to 300 Mbit/s). If this is not possible due to
interference or channels already being used by other
WLANs in the vicinity, the FRITZ!Box automatically switches
over to a channel with 20 MHz bandwidth. Greater band-
width provides for higher data throughput:
Increasing bandwidths also increases the probability of in-
terference by wireless networks in the vicinity. Large band-
widths reduce the frequency range available to other wire-
less networks in the vicinity.
Bandwidth (MHz)
Maximum Data Throughput (Mbit/s)
20
130
40
300
