User`s guide

126 N9320A Spectrum Analyzer
5 One-Button Measurements
OBW Span Specifies the integration range used to calculate the total
power from which the percent occupied bandwidth is then
calculated. The analyzer span will be set to the same value
as the OBW Span for the measurement. OBW Span should
be set to an approximate multiple of 2
times the expected
occupied
bandwidth result. The range is from 100 Hz to 3
GHz.
Key access:
> Occupied BW
x dB Specifies the power level used to determine the emission
bandwidth as the number of dB down from the highest
signal point, within the occupied bandwidth span. This
function is an independent calculation from the OBW
calculation. The x dB Bandwidth result is also called the
emissions bandwidth, or EBW. Two arrows will be set to the
specified dB value below the maximum power level and the
total power between the arrows will be computed.
Frequencies f1 and f2 are determined as the furthest
frequencies x dB below and above maximum power level,
respectively. The emission bandwidth is then calculated as f2
– f1 as shown by the arrows indicated in Figure 29 (note
that the diamond markers are for the OBW function). The
range is from –100.0 to –0.1 dB.
Key access:
> Occupied BW
Meas
Meas
NOTE
The asterisk next to the x dB bandwidth value in Figure 29 indicates
the results may not have been determined with optimal analyzer
settings. If emission bandwidth is your primary interest, select Max
Hold. Then change detector mode to peak by pressing
>
Detector > Positive Peak. Acquiring peak data ensures accuracy of
this measurement.
Det/
Display