Glossary: Frequently Used Terms
R&S
®
ZNC
753
User Manual 1173.9557.02 ─ 13
tings complement the definitions of the Trace menu; they apply to all traces assigned to
the channel.
Compression point:
The x-dB compression point of an S-parameter or ratio is the stim-
ulus signal level where the magnitude of the measured quantity has dropped by x dB
compared to its value at small stimulus signal levels (small-signal value).
Confirmation dialog box:
Standard dialog box that pops up to display an error message
or a warning. The current action can be either continued (OK) or cancelled (Cancel) on
closing the dialog box.
Crosstalk:
The occurrence of a signal at the receive port of the analyzer which did not
travel through the test setup and the DUT but leaks through other internal paths. Crosstalk
causes an isolation error in the measurement which can be corrected by means of a
calibration.
CW frequency:
Continuous Wave frequency; fixed stimulus frequency used in Power,
CW Time and CW Mode sweeps.
D
Data trace:
Trace filled with measurement data and updated after each sweep (dynamic
trace).
Diagram area:
Rectangular portion of the screen used to display traces. Diagram areas
are arranged in windows; they are independent of trace and channel settings.
Directivity error:
Measurement error caused by a coupler or bridge in the analyzer's
source port causing part of the generated signal to leak through the forward path into the
receive path instead of being transmitted towards the DUT. The directivity error can be
corrected by means of a full one port calibration or one of the two-port calibration methods
(except normalization).
Discrete marker:
The stimulus value of a discrete marker always coincides with a sweep
point so that the marker does not show interpolated measurement values.
DUT:
Device under test; generic term for any electrical device or circuit which the vector
network analyzer can measure. Typical DUTs are filters, amplifiers, or mixers.
E
Excursion:
Difference between the response values at a local maximum (minimum) of
the trace and at the two closest local minima (maxima) to the left and to the right.
Extrapolation:
Calculation of a numeric value for a new sweep point outside the original
sweep range from the numeric values of the existing sweep points. The analyzer can
extrapolate calibration data, transmission coefficients etc. in order to extend the sweep
range. If not otherwise stated, the numeric value of the first (last) sweep point is assigned
to all new points below (above) the original sweep range. See also --> interpolation.
