Concepts and features
R&S
®
ZNB/ZNBT
135
User Manual 1173.9163.02 ─ 62
●
Y
12
is the reverse transfer admittance, defined as the ratio of the current I
1
to the
voltage V
2
(reverse measurement with input terminated in a short circuit, V
1
= 0).
●
Y
22
is the output admittance, defined as the ratio of the current I
2
to the voltage V
2
,
measured at port 2 (reverse measurement with input terminated in a short circuit,
V
1
= 0).
Y-parameters can be easily extended to describe circuits with more than two ports or
several modes of propagation.
4.3.5
Wave quantities and ratios
The elements of the S-, Z- and Y-matrices represent fixed ratios of complex wave
amplitudes. As long as the assumption of linearity holds, the S-, Z- and Y-parameters
are independent of the source power.
The network analyzer provides two additional sets of measurement parameters which
have an unambiguous meaning even if the DUT is measured outside its linear range:
●
Wave quantities
provide the power of any of the transmitted or received waves.
●
Ratios
provide the complex ratio of any combination of transmitted or received
wave quantities.
In contrast to S-, Z- and Y-parameters, wave quantities and ratios are not system-error
corrected.
To increase the accuracy or to correct a possible attenuation in the source signal path,
it is recommended to perform a power calibration (see
4.3.5.1
Wave quantities
A wave quantity measurement provides the power of any of the transmitted or received
waves. The power can be displayed in voltage units (e.g. V or dBmV) or equivalent
power units (e.g. W or dBm).
Examples for using wave quantities
The wave quantities provide the power at the different receive ports of the analyzer.
This is different from an S-parameter measurement, where the absolute power of a lin-
ear device is canceled. Wave quantities are therefore suitable for the following mea-
surement tasks:
●
Analysis of nonlinearities of the DUT.
●
Use of the analyzer as a selective power meter.
To increase the accuracy or to correct a possible attenuation in the source signal
path, it is recommended to perform a power calibration (see
Measurement results
