China Electronics Technology Instruments AV3672 Series, Руководство пользователя

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7 Calibration
7.6 Editing of Calibration Kit Definition
218
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Eliminate source matching errors by means of error correction in reflection and transmission measurement.
5) Reflection tracking errors
The signals of Receiver A and R1 or B and R2 are compared in reflection measurement. This is known as ratio
measurement. In the ideal reflection measurement, the frequency responses of Receiver A and R1 or B and R2
should be identical. Actually, this is impossible and reflection tracking errors may be produced, i.e. vector sum
errors caused by test deviations. The error amplitude and phase change with the frequency. Deviations are mainly
caused by the following factors:
➢
Signal separator;
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Test cable and adapter;
➢
Difference between the reference and test signal paths.
Reflection tracking errors can be determined and reduced in the following methods.
➢
Connect the short-circuit device to the measurement port in calibration. The signals reflected by the short-
circuit device will be measured by the receiver. Measurement results will be saved in the analyzer.
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Connect the open-circuit device to the port. The signals reflected by the open-circuit device will be measured
by the receiver. Measurement results will be saved in the analyzer.
➢
The measurement results will be compared with the known values of the open-circuit device and short-circuit
device to determine source matching errors.
➢
Eliminate reflection tracking errors by means of error correction in reflection and transmission measurement.
6) Transmission tracking errors
The signals of Receiver A and R2 or B and R1 are compared in transmission measurement. This is known as ratio
measurement. In the ideal transmission measurement, the frequency responses of Receiver A and R2 or B and R1
should be identical. Actually, this is impossible and transmission tracking errors may be produced, i.e. vector sum
errors caused by test deviations. The error amplitude and phase change with the frequency. Deviations are mainly
caused by the following factors:
➢
Signal separator;
➢
Test cable and adapter;
➢
Difference between the reference and test signal paths.
Transmission tracking errors can be determined and reduced in the following methods.
➢
Directly connect Port 1 and 2, with zero length.
➢
Measure the signals of Receiver A and R2 or B and R1.
➢
Determine transmission tracking errors by comparing the signals of two receivers.
➢
Eliminate transmission tracking errors by means of error correction in transmission measurement.
7.6 Editing of Calibration Kit Definition
The [Edit calibration kit] dialog box is used to edit the definition of the calibration kit or create a user-defined
calibration kit.
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Calibration kit definition ·························································································· 219
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Custom calibration kit
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Create calibration kit
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Edit calibration kit
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[Edit calibration kit] dialog box
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[Add connector] dialog box
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