Campbell RF401A Series, Инструкция по эксплуатации

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RF401A-Series Spread Spectrum Radio
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11.3.4 Received Signal Strength
Indicates the signal strength of the last packet received addressed to this radio
and with a valid CRC. The range of values reported, generally between 6 and
54, represent the approximate range from –110 dBm to –35 dBm with each
value representing a little less than 2 dB. The table below displays signal
strength values and the corresponding dBm level. Because the received signal
strength can vary due to multipath, interference or other environmental effects,
it may not give a true indication of communication performance or range.
However, received signal strength can be useful for activities such as:
•
determining the optimal direction to aim a Yagi antenna
• determining the effects of antenna height and location
• trying alternate (reflective) paths
•
seeing the effect of vegetation and weather over time
Appx. Signal Level (dBm) Indicator Value
–35 50
–40 49
–45 48
–50 47
–55 46
–60 45
–65 44
–70 42
–75 41
–80 39
–85 37
–90 34
–95 30
–100 24
–105 17
–108 11
Accessing the received signal strength indicator (RSSI)
• Direct connection –
Using a direct connection from the PC to the RF401A USB port,
DevConfig
can be used to view the received signal strength indicator
(RSSI). Once a connection is established using DevConfig, the
Received Signal Strength can be located under the Advanced tab.
•
Datalogger Query –
The RF401A must be set up as a PakBus Node using
DevConfig
.
Under the
Main
tab, set the
Protocol
to
PakBus Node
. This setting
makes the RF401A an independent device in the network. The