User guide

AirMagnet Spectrum XT User Guide
Chapter 6: Analyzing Spectrum Data 67
The text message at the bottom of the Real Time FFT Configuration dialog box changes with the
parameter you select. It provides a brief description of the parameter being selected.
Spectrum Density Graph
The Spectrum Density graph shows the “popularity” of a particular frequency/power reading
over time. The X-axis shows the frequency or channel for the selected 802.11 radio band; the Y-
axis shows the minimum and maximum power readings in dBm. See Figure 6-6.
Spectrum Type Allows the user to decide where (which part of the FFT graph) the marker or
markers should fall. Click in the field and use the down arrow to select one of the
following:
• Current - places the marker or markers on the Current power readings. (The
marker may jumps up and down as the curve line changes, because this
curve reflects the real-time change of power readings across the spectrum.)
• Average - places the marker or markers on the Average power readings.
• Maximum - places the marker or markers on the Maximum power readings.
Enable Tool Tip Allows the user to show or hide the tool tip (on the FFT graph), which provides
the current, average, and maximum power readings as well as the frequency at
the point the cursor rests upon. Click in the field and use the down arrow to
select either of the following:
• Yes - shows the tool tip.
• No - hides the tool tip.
Minimum Power Allows the user to set or change the minimum power level on the Y-axis. By
default, it is set at -120 dBm, but it can be set to as low as -140 dBm. Highlight the
existing value and override it with a new value.
Peak Power Allows the user to set or change the maximum power level on the Y-axis. By
default, it is set at -20 dBm, but you can change it to any value less than 0 dBm.
Highlight the existing value and override it with a new value.
Start Frequency Allows the user to set or change the start point of a frequency range. Highlight
the existing value and override it with a new value.
Stop Frequency Allows the user to set or change the end point of a frequency range. Highlight
the existing value and override it with a new value.
Table 6-2: Setting Real Time FFT Graph Parameters
Parameter Description