China Electronics Technology Instruments AV3672 Series, User Manual

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4 Measurement Setting
4.2 Selection of Measurement Parameter
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[Reset] shortcut key
The [Reset] shortcut key is set in the functional key zone and shortcut menu bar.
4.2 Selection of Measurement Parameter
The following parameters can be set in an AV3672 series vector network analyzer to measure the electrical
characteristics of devices.
➢
S parameter (fixed ratio)
➢
Any ratio (custom ratio for measurement)
➢
Non-ratio power measurement (absolute power measurement)
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S parameter ··········································································································· 88
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Any ratio ·············································································································· 90
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Non-ratio power measurement ······················································································ 90
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Change of trace measurement type ················································································· 91
4.2.1 Parameter S
1) Overview of Parameter S
The parameter S (scattering parameter) is used to describe the change of input signal and the reflection and
transmission characteristics of the DUT. The S-parameter is shown in the prescribed digit row, and indicates the
proportion of two complex vectors, i.e. S
output/input
, including the amplitude and phase information. The output refers
to the output signal port number of the DUT, and the input refers to the input signal port number of the DUT. The
analyzer is equipped with four test ports to test single-port, double-port, three-port and four-port devices.
For example, when one double-port device is connected to Port 1 and 2, four parameters (S) can be measured at the
same time.
In this case, the four parameters (S) of the double-port device are respectively S11, S12, S21 and S22. Fig. 4.3
further shows the parameter S, where:
➢
a refers to the stimulus signal from the input to DUT.
➢
b refers to the reflection and transmission signal (response signal) of the DUT.
The parameter S is a plural linear value. The measurement accuracy depends on the indicators of the calibrator and
the adopted technology of measurement connection, and is also associated with the connection of the non-
measurement port (non-excited port).
2) Application of parameter S
The following parameters can be measured with S.
a) Reflection measurement: SXX (X=1, 2, 3, 4)
i. Return loss
ii. Standing wave ratio (SWR)
iii. Reflection coefficient
iv. Impedance
v. S11, S22, S33 and S44
b) Transmission measurement: SXY (X=1, 2, 3, 4; Y=1, 2, 3, 4; X≠Y)
i. Insertion loss
ii. Transmission coefficient