Rohde & Schwarz FSQ series, Quick Start Manual

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Quick Start Guide 1313.9652.62 - 02 5.21
R&S FSQ Basic Measurement Examples
Measurements in the Time Domain
5.5 Measurements in the Time Domain
In the case of radio transmission systems that use the TDMA method (e.g. GSM or IS136),
transmission quality is determined not only by spectral characteristics but also by
characteristics in the time domain. However, a timeslot is assigned to each user since several
users share the same frequency. Smooth operation is ensured only if all users adhere exactly
to their assigned timeslots.
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.
5.5.1 Measuring the Power Characteristic
For measuring power in the time domain, the R&S FSQ offers easy-to-use functions that
measure the power over a predefined time.
5.5.1.1 Example – Measuring the Power of a GSM Burst During the Activation Phase.
Test setup:
Settings on the signal generator (e.g. R&S SMIQ):
Measurement with the R&S FSQ:
1. Reset the instrument.
➢
Press the PRESET key.
The R&S FSQ is now in the default state.
2. Set the center frequency to 100 MHz, the span to 0 Hz and the resolution bandwidth
to 1 MHz.
➢
Press the FREQ key and enter 100 MHz .
➢
Press the SPAN key and enter 0 Hz , or press the ZEROSPAN softkey.
3. Set the reference level of the R&S FSQ to 10 dBm (= level of the signal generator
+10 dB).
➢
Press the AMPT key and enter 10 dBm .
Frequency: 100 MHz
Level: 0 dBm
Modulation: GSM, one timeslot activated
Signal
generator
R&S FSQ