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

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Channel Menu R&S
®
ZVA/ZVB/ZVT
1145.1084.12 4.158 E-6
Most of the settings in this section require option ZVA-K4, Arbitrary Generator and Receiver
Frequencies. This option is available for ZVT network analyzers only.
•
LO a/b switch the two Local Oscillator amplifiers at the port on (box checked) or off.
Both LOs must be switched on to perform a system error correction.
•
Frequency opens an input box to define a converted receiver frequency range (for frequency
sweeps) or CW frequency (for power, time and CW Mode sweeps). The converted receiver
frequencies are valid for all ports. In the default configuration the stimulus parameters (sweep
range,
CW Frequency) are used. The result is indicated in the Frequency Result column.
•
Frequency Result displays the current frequency range (for frequency sweeps) or CW
frequency (for power, time and CW Mode sweeps); see stimulus parameters.
•
PCor Off enables or disables a receiver power calibration for an individual port. This function is
available only for ports where a receiver power calibration is available. It is identical with
Receiver Power Correction Off in the Receiver Power Cal menu.
•
Atten defines port-specific attenuation factors for the received wave. The settings are
analogous to the global Step Attenuator settings and replace them.
•
IF Gain b selects the IF gain in the receiver path.
The settings are valid for all ports:
•
Auto means that the analyzer adapts the IF gain to the RF input level (Automatic or
Adaptive Gain Control, AGC). The A/D converter is always operated at optimum input
level.
The following settings accelerate the measurement:
•
Low Dist(ortion) corresponds to a small IF gain(i.e. a lower internal A/D converter input
level). This setting allows for a high RF overdrive reserve and is appropriate for high RF
input levels.
•
Low Noise corresponds to a large IF gain(i.e. a higher internal A/D converter input
level). This settingincreases the dynamic range and is appropriate for low RF input
levels.
The Low Dist or Low Noise settings are appropriate whenever the characteristics of the input
path must be constant, e.g. because:
•
Interfering signal contributions originating from the receiver (noise, nonlinear
contributions) must not change during the measurement.
•
A large interfering signal in the vicinity of the measured signal must not overdrive the
receiver.
Remote control: [SENSe<Ch>:]LOMeasure
[SENSe<Ch>:]LOReference
[SENSe<Ch>:]FREQuency:STARt?