MEDITRONIK Wi-Net Window, Дополнение к инструкции по эксплуатации

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For more technical users a signal
strength measurement in dBm is
sometimes preferred. dBm is an
abbreviation for the power ratio in
decibel (dB) of the measured power
referenced to one milliwatt (mW). It is
used in radio, microwave and fiber optic
networks as a convenient measure of
absolute power because of its capability
to express both very large and very
small values in a short form. Zero dBm
equals one milliwatt. A 3 dB increase
represents roughly doubling the power,
which means that 3 dBm equals roughly
2 mW. For a 3 dB decrease, the power
is reduced by about one half, making −3
dBm equal to about 0.5 milliwatt.
For these more technical users, an
option to display signal strength in dBm
has been added to the Wi-Net Window.
This is accessed via the Expert Setup
sub-menu (see menu navigation chart in
a later section).
Press the SEL key to cycle between
dBm and percentage (%). When dBm is
selected the CAL icon is shown on the
scan display. The 10 LEDs on the Wi-Net
always indicate the percentage signal
strength.
For wireless networks the signal strength
ranges from around –20 dBm to –90
dBm. When the AP is out-of-range the
signal strength is displayed as –99 dBm.
Scan Rate
The Wi-Net Window actively scans
for existing wireless networks. Active
scanning is much quicker and more
responsive than passive scanning. By
default the Wi-Net scans the current
(i.e. displayed) network once every two
seconds and scans for all networks
once every six seconds. If a hidden
SSID is specified (see section below), it
is scanned every four seconds. Since
active scanning requires more power,
these rates were chosen as a reasonable
balance between functionality and battery
life.
SETUP
2 1 4 5 6 7 8 S
CAL
E