Rohde & Schwarz 1145.1010.04/05/06, Руководство по эксплуатации

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Reflection Measurements R&S
®
ZVA/ZVB/ZVT
1145.1084.12 2.2 E-1
Reflection Measurements
In a reflection measurement, the analyzer transmits a stimulus signal to the input port of the device
under test (DUT) and measures the reflected wave. A number of trace formats allow you to express and
display the results. depending on what you want to learn from the data. Only one analyzer test port is
required for reflection measurements.
In the following example, the analyzer is set up for a reflection measurement, a frequency sweep range
and measurement parameter is selected, the instrument is calibrated and the result is evaluated using
various formats.
Instrument Setup for Reflection Measurements
In order to prepare a reflection measurement, you have to connect your DUT (which is assumed to
have a male N 50
Ω
connector) to one of the (equivalent) analyzer test ports. Besides, it is
recommended to preset the instrument in order to set it to a definite, known state.
1. Proceed as described in section Starting the Analyzer
and Shutting Down to switch on the instrument and
start the NWA application.
2. Connect the input port of your DUT to test port 1 of
the network analyzer.
3. Press the preset key in the SYSTEM keypad to
perform a factory preset of the analyzer.
The analyzer is now set to its default state. The default
measured quantity is the transmission S-parameter S
21
. This
quantity is zero in the current test setup, so the trace shows
the noise level.
Press the TRACE SELECT key in the TRACE keypad and use the softkeys in the Trace Select
menu if you wish to create a new trace or a new diagram area.