Agilent Technologies 4395A, Ручное изменение

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Data Processing
Frequency Characteristics Correction by Corrective Data Arrays
This corrects the frequency response for absolute measurement value , using corrective
data arrays . If the selected measurement is ratio (for example , A/R or B/R), no operation is
performed.
A veraging
This is one of the noise reduction techniques . This calculation involves taking the complex
exponential average of up to 999 consecutive sweeps . See \A veraging (Sweep A veraging)"
under the heading \Network Measurement Basics" in this chapter .
Raw Data Arrays
These arrays store the results of all the preceding data processing operations . When full 2-port
error correction is on, the raw data arrays contain all four S-parameter measurements required
for accuracy enhancement. When the channels are uncoupled (coupled channels off ), there
may be as many as eight raw data arrays . These arrays are directly accessible via GPIB , or
using the internal disk drive or the memory disk. Note that the numbers here are still complex
pairs .
Calibration Coecient Arrays
When a measurement calibration has been performed and correction is turned on, error
correction removes the repeatable systematic errors (stored in the calibration coecient arrays)
from the raw data arrays . This can vary from simple vector normalization to full 12-term error
correction.
The calibration coecient arrays themselves are created during a measurement calibration
using data from the raw data arrays . These are subsequently used whenever correction is on,
and are accessible via GPIB , or using the internal disk drive or the memory disk.
Data Arrays
The results of error correction are stored in the data arrays as complex number pairs . These
arrays are accessible via GPIB or by using the internal disk drive or the memory disk.
Memory Arrays
If the data-to-memory operation is performed (using the
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DATA ! MEMORY softkey), the data
arrays are copied into the memory arrays (data trace arrays are also copied into the memory
trace array at same time). These arrays are accessible using the internal disk drive or the
memory disk. When accessed via GPIB , these arrays are read-only .
If memory is displayed, the data from the memory arrays goes through the same data
processing ow path as the data from the data arrays .
Electrical Delay and Phase Oset
This involves adding or subtracting a linear phase in proportion to frequency . This is equivalent
to \line-stretching" or articially moving the measurement reference plane . F or more
information, see \Electrical Delay" under the heading \Network Measurement Basics" in this
chapter . .
Conversion
Transforms S-parameter measurement data into equivalent complex impedance (Z) or
admittance (Y) values , to inverse S-parameters (1/S), or to phase multiples of 4, 8, or 16. See
\Conversion Function " under the heading \Network Measurement Basics" in this chapter . .
Basic Measurement Theory A-5