Afar AR24027, Руководство оператора

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AR24027 Operator’s Manual
4-13
spectrum-analysis
input=a-antenna or b-antenna
display=graph or table
dwell-time-ms=1..1000
This command switches the receiver to the specified antenna (defaults to A) and then performs
a scan of
all the channels from 2.400 to 2.500 MHz, dwelling on each channel for the specified
amount of time (defaults to 20 milliseconds). While on each channel it measures the RSSI for
that channel and stores its peak value. It then displays the data collected in a graphical or table
formats (defaults to “graph”).
Note that even though the AR24027 channels are spaced 2 MHz apart, the receiver RF
bandwidth is approximately 5 MHz. Therefore the RSSI value reported for each channel
represents the total energy in a 5 MHz band centered around that channel. For this reason, a
narrow band transmitter will show up in the spectrum analysis report as a lobe with 5 MHz
bandwidth. Conversely, you do not need to find a quiet 5 MHz wide region in the spectrum
analysis report to select a quiet channel, i.e., any single channel sample that shows a low
“noise” level, is a good candidate to select as a receive channel.
Examples:
>spectrum-analysis input=b-antenna
>spa dwell=500
time-analysis
channel=0..50
input=a-antenna
or b-antenna
display=graph or table
dwell-time-ms=1, 2, 5, 10, 20, 50, 100, 200, 500
This command switches the receiver to the specified antenna (defaults to A) and then measures
the RSSI for a
single channel over a period of time. Each “sample” consists of the maximum
RSSI measured during the dwell time specified (defaults to 20 milliseconds). After collecting
60 samples the RSSI values are displayed graphically or numerically (defaults to “graph”).
Example:
>time-analysis input=b-antenna
>tia in=a dis=t dwell=500
4.7 File Utilities
The AR24027 maintains a file system that allows multiple programs to be stored in either non-volatile
flash PROM or volatile RAM. New programs can be downloaded into the AR24027 memory through
the auxiliary port, through the Ethernet port, or to a remote radio across the RF link.
One of the programs in flash PROM is designated as the default program to run after reboot. On
power up that program is copied from PROM into RAM and the code runs out of RAM.