Rohde & Schwarz 1145.1010.04/05/06, Operating Manual

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Trace Evaluation R&S
®
ZVA/ZVB/ZVT
1145.1084.12 9.8 E-4
Trace Evaluation
Time Domain Measurements
With option ZVAB-K2, Time Domain, you can view the measurement results as a function of time.
To set up a time domain measurement...
1. Reset the analyzer to ensure that the following operating mode is set: Sweep Type: Lin.
Frequency, Trace - Meas.: S21, Trace - Format: dB Mag .
2. Open the Trace - Meas menu and select the measured quantity to be transformed (preferably:
an S-parameter or ratio).
3. Click Trace - Trace Func - Transform - Time Domain to transform the active trace to the time
domain.
The transformed trace is displayed in the active diagram area. To refine the analysis, you can modify
the number and position of the sweep points
(Channel - Sweep - Number of Points, Channel -
Stimulus), select a different transform type and window for profiling (Trace - Trace Func - Transform -
Define Transform...) and vary the time range (Trace - Trace Func - Transform - Time Domain Stimulus
Axis...).
To eliminate an unwanted response from the measured trace...
1. Calculate a time domain transform as descibed above, Setting up a time domain measurement.
2. Click Trace - Trace Func - Transform - Define Time Gate and place a time gate on the
transformed trace. To remove a single response use a Notch gate type. To everything outside a
specified area, use a Bandpass gate type.
3. Click Trace - Trace Func - Transform - Time Gate to enable the time gate. If necessary, go
back to the Define Time Gate dialog to correct your time gate settings.
4. Click Trace - Trace Func - Transform - Frequency Domain.
The frequency domain trace now corresponds to the modified time domain trace which is transformed
back into the frequency domain
.
Trace Statistics
After measuring a quantity across the selected sweep range, the analyzer can analyze the trace and
determine various statistical results.
To determine the x-dB compression point...
1. Press the Sweep key in the Channel keypad or click Channel - Sweep to access the Sweep
submenu.
2. Click Sweep Type - Power. In the CW Frequency input field opened, enter the fixed stimulus
frequency for the power sweep.
3. Click Channel - Stimulus - Start and Channel - Stimulus - Start to define the power sweep
range.