Atec Agilent-8722ES - Manual (Page 21)

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TRL*/LRM* calibration
Compensates for directivity, reflection, and trans-
mission frequency response, and crosstalk in both
the forward and reverse directions. Especially suit-
able for calibrating non-coaxial environments, such
as in test fixtures. TRL*/LRM* is a special imple-
mentation of TRL/LRM calibration, modified for
the three-sampler receiver in the standard 8719ES/
8720ES/8722ES analyzers.
TRL/LRM calibration
With Option 400 (four-sampler receiver), TRL/LRM
provides the highest accuracy for non-coaxial test
environments such as in-fixture, on-wafer, or in-
waveguide. Compensates for directivity, reflection
and transmission frequency response, and crosstalk
in both forward and reverse directions. Available
as an option on 8719ES/20ES/22ES analyzers.
Interpolated error correction
With any type of accuracy enhancement applied,
interpolated mode recalculates the error coeffi-
cients when the test frequencies are changed. The
number of points can be increased or decreased
and the start/stop frequencies can be changed,
but the resulting frequency span must be a subset
of the original calibration frequency span. System
performance is not specified for measurements
with interpolated error correction applied.
Set Z
o
Redefine the characteristic impedance of a meas-
urement to a value other than 50 ohms.
Velocity factor
Enter the velocity factor of your propagation
medium to convert equivalent electrical length to
physical length.
Electrical delay
Add or subtract delay (linear phase slope), up to
+10 µs, similar to “line stretchers,” both coax or
wave-guide (dispersive) modes. Secondary readout
in distance computed from velocity factor.
Reference plane extension
Redefine the reference plane after calibration. A
new reference plane is defined in seconds of delay
from the test port and ranges between ±1 seconds.
Similar to electrical delay, but applied appropriately
to each of four parameters.
Select default calibration kit
Select from a list of standard calibration kits:
7 mm, 3.5 mm, Type-N 50 ohm, 2.4 mm, 7-16,
2.92 mm, and 3.5 mm TRL. You can also define the
standards (for example, open-circuit capacitance
coefficients, offset short length, or fixed loads)
of a user-defined kit.
Segmented calibration
Calibration remains valid for any frequency seg-
ment (in frequency list mode), after calibrating
all segments with a single calibration.
Receiver power calibration
Adjusts nonratioed receiver inputs to absolute
(non-ratioed) power level. Displays absolute power
in dBm. Requires reference sweep of known source
power.
Data averaging
IF bandwidth
The IF bandwidth is selectable from 6 kHz to 10 Hz
to reduce the effective displayed noise floor of the
instrument.
Weighted sweep-to-sweep averaging
This function averages vector data on each succes-
sive sweep: where A(n) is the current average, S(n)
is the current input signal and F is the averaging
factor. Averaging factors range from 1 to 999.
A(n) = S(n)/F + (1–1/F)
x A(N–1)
Trace smoothing
Similar to video filtering, this function computes
the moving average of adjacent data points. The
smoothing aperture defines the trace width (num-
ber of points) to be averaged, and ranges from
0.25% to 20% of the trace width. This function also
sets the aperture for group delay measurements.