130 Chapter 2 
Front-Panel Key Reference
Meas Setup
x dB  Allows you to specify the power level used to determine the emission 
bandwidth as the number of dB down from the highest signal point (P
1
), 
within the occupied bandwidth span. Frequencies f
1
 and f
2
 are 
determined as the furthest frequencies x dB below and above P
1
, 
respectively. The emission bandwidth is then calculated as f
2
 
−
 f
1
 as 
shown in Figure 6-1. 
NOTE The asterisk next to the x dB value in Figure 2-4 indicates the results 
may not have been determined with optimal analyzer settings. If 
emission bandwidth is your primary interest, select 
Meas Setup, Max 
Hold
. Then change detector mode to peak by pressing Det/Demod, 
Detector, Peak. Acquiring peak data ensures accuracy of this 
measurement.
Figure 2-4  Occupied Bandwidth Measurement Results
cdma2000  SR3  BTS/MS 6.0 MHz 1 MHz/
100 kHz
PDC N/A BTS/MS 31.5 kHz 3 kHz/
300 Hz
1. Maximum RBW available and < 1% of the OBW span.
Table 2-3  Occupied Bandwidth Default Settings for Radio Standards
Standard Format Device OBW 
Span
VBW/RBW
P1
f2
f1fff1