Agilent Technologies 4395A - Page 381

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
Coecient
Arrays
When
a
measurement
calibration
has
been
performed
and
correction
is turned
on, error
correction
removes
the
repeatable systematic
errors (stored
in
the
calibration
coecient
arrays)
from
the
raw
data arrays
. This
can
vary
from
simple
vector
normalization
to
full
12-term
error
correction.
The
calibration
coecient
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
N
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NN
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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 Oset
This involves adding or subtracting a linear phase
in proportion to frequency
. This is equivalent
to \line-stretching" or articially 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