The Spectrum Application (RF Measurements)
R&S
®
FPL1000
248
User Manual 1178.3370.02 ─ 03
Measuring the Power Characteristic of Burst Signals
To measure power in zero span, the R&S
FPL1000 offers easy-to-use functions that
measure the power over a predefined time.
Measuring the Power of a GSM Burst During the Activation Phase
Figure 7-13: Test setup
Table 7-6: Signal generator settings (e.g. R&S SMW)
Frequency
890 MHz
Level
0 dBm
Modulation
GSM, one timeslot activated
1. Select PRESET to reset the instrument.
2. Set the center frequency to
890
MHz
(FREQ).
3. Set the frequency span to
0
Hz
(SPAN > "Zero Span" ).
4. Set the reference level to
10
dBm
(= level of the signal gen10
dB) (AMPT).
5. Set the attenuation to
20
dB
(AMPT > "RF Atten Manual" ).
6. Set the resolution bandwidth to
1
MHz
(BW > "Res BW" ).
7. Set the sweep time to
1
ms
(SWEEP > "Sweep Time Manual" ).
The R&S
FPL1000 shows the GSM burst continuously across the display.
8. Using the video trigger, set triggering on the rising edge of the burst.
a) Press the TRIG key.
b) Set the "Trg Source" to "Video" .
c) Set the "Trg/Gate Level" to
70%
.
The R&S
FPL1000 shows a static image with the GSM burst at the start of the
trace. The trigger level is displayed as a horizontal line labeled with the absolute
level for the trigger threshold in the measurement diagram.
9. Activate power measurement within the activation phase of the burst in zero span.
a) Press the MEAS key.
b) Select "Time Domain Power" .
c) Select "Time Dom Power Config" .
d) Set the "Limits" state to "On" .
e) Select the "Left Limit" input field.
f) By turning the rotary knob clockwise, move the vertical line "S1" to the start of
the burst.
Measurements and Results
