Glossary: Frequently Used Terms
R&S
®
ZNC
754
User Manual 1173.9557.02 ─ 13
F
Forward:
A measurement on a two-port DUT is said to be in forward direction if the source
signal (stimulus) is applied to port 1 of the DUT.
H
Harmonic:
Integer multiple of the fundamental frequency. The fundamental is the first
harmonic, the nth harmonic is n times the frequency of the fundamental.
Harmonic distortion:
The production of harmonic frequencies (harmonics) by an elec-
tronic system when a signal is applied at the input.
Harmonic grid:
A set of equidistant frequency points f
i
(I = 1...n) with spacing Delta(f)
and the additional condition that f
1
= Delta(f). A harmonic grid is required for low pass
time domain transforms.
I
Intercept point:
Fictitious lower-tone DUT input/output level where the intermodulation
suppression (-->) for a given intermodulation product reaches 0 dB.
Intermodulation measurement:
Measurement where the DUT is supplied with two RF
signals of equal power but different frequencies termed the upper and lower tone. The
analyzer measures the frequency-converting behavior of the DUT (--> intermodulation
product).
Intermodulation product:
Special type of emissions of a nonlinear DUT that is supplied
with a two-tone RF signal (--> intermodulation measurement). The intermodulation prod-
ucts occur at frequencies which correspond to sums and differences of the upper and
lower tone frequencies and their integer multiples.
Intermodulation suppression:
The ratio of the power of an --> intermodulation product
to the power of the lower tone fundamental wave.
Interpolation:
Calculation of a numeric value for a specific sweep point from the numeric
values of the adjacent points. The analyzer can interpolate calibration data, transmission
coefficients etc. in order to account for a modified set of sweep points. If not otherwise
stated, linear interpolation is used. See also --> extrapolation.
Isolation error:
Measurement error caused by a crosstalk between the source and
receive port of the analyzer.
L
Limit check:
Comparison of the measurement results with the limit lines and display of
a pass/fail indication. An acoustic warning can be generated in addition if a limit is excee-
ded.