Ronde & Schwarz 1304.0004.03, Руководство пользователя

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The Spectrum Application (RF Measurements)
R&S
®
FPL1000
112 User Manual 1178.3370.02 ─ 09
Both the power during the send phase as well as the timing and duration of the TDMA
burst, and rise and fall times of the burst, are important.
● Measuring the Power Characteristic of Burst Signals ........................................... 112
● Measuring the Signal-to-Noise Ratio of Burst Signals .......................................... 115
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".
Measurements and Results