China Electronics Technology Instruments AV3672 Series, Руководство пользователя

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Appendix
Appendix 3 Frequency Offset Measurement
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coupling mode. The coupling frequency setting range can be calibrated with the main setting value by the specified
mathematical equation according to the multiplier and divisor settings (detailed in next section). In this method, the
source and receiver parameters can be changed by changing the main setting. The main setting parameter can be
changed only in the frequency offset ON mode.
The main setting cannot be used until the source and receiver are set in the coupling mode. The non-coupling mode
is used more commonly. In this case, the source and receiver parameters can be set separately. Click
[Stimulus] >
[Power] > [Power and Attenuator] to set Source 2.
Receiver : all the receivers in the channel, including the reference receiver, can be adjusted by the “Setting”
item to the specific frequency.
Sweep type : set for each item.
Pay attention to the following items:
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Power canning and segment sweep cannot be applied at the same time;
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Invalid data will be produced in case of source and receiver deviations in the non-coupling logarithmic
frequency sweep mode;
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The coupling logarithmic frequency sweep mode can be applied in the following two cases:
1) Frequency offset=0, multiplier=1 and divisor=1.
2) Multiplier=0.
X-axis display : select the X-axis display mode in the window.
Y-axis uniform interval display : for segment sweep.
Attention
Frequency offset function:
If the frequency offset function is enabled, all receivers of channels, including the reference receiver, will be
adjusted to the set value. In this case, the source frequency is different from the receiver frequency, resulting in
inaccurate S-parameter measurement data of all receivers, including the reference receiver. Double-channel
measurement must be applied to measure and display accurate results in the source and receiver frequency
measurement. The frequency offset and loss can be calibrated by the equation editor. The calibration method is
introduced in the following section.
3.2 Setting of Coupling and Non-coupling Mode
3.2.1 Setting of Coupling Mode
Click [Stimulus] > [Power] > [Power and Attenuator] in the menu bar and open the [Frequency Offset] dialog
box. Right-click the setting bar and click the pop-up [Edit] menu. The [Source coupling setting] dialog box will
pop up, as shown in the following figure.
Fig. 3.3 [Source 1 coupling setting] Dialog Box
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Coupling equation: