R&S ZVB - Page 219

R&S
®
ZVA / R&S
®
ZVB / R&S
®
ZVT GUI Reference
Trace Menu
Operating Manual 1145.1084.12 – 30 204
All marker formats are available irrespective of the measured quantity. The output values are calculated
by a simple conversion of a complex measurement result, where the marker format defines the conversion
rules. This flexibility in the calculation must be kept in mind when interpreting the results and physical units
displayed; see also Measured Quantities and Display Formats.
Note that the calculation of interpolated marker values is based on the current trace format, so changing
the trace format may also affect the displayed marker values.
Short description of marker formats
The formats of the markers assigned to a trace are independent of each other and of the trace format
settings. The following table gives an overview on how a complex marker value z = x + jy is converted.
Marker Format
Description
Formula
dB Mag
Magnitude of z in dB
|z| = sqrt ( x
2
+ y
2
)
dB Mag(z) = 20 * log|z| dB
Lin Mag
Magnitude of z, unconverted
|z| = sqrt ( x
2
+ y
2
)
Phase
Phase of z
φ (z) = arctan (y/x)
Real
Real part of z
Re(z) = x
Imag
Imaginary part of z
Im(z) = y
SWR
(Voltage) Standing Wave Ratio
SWR = (1 + |z|) / (1 – |z|)
Delay
Group delay, neg. derivative of the phase response*
)
– d φ (z) / d ω
dB Mag and Phase
Magnitude of z in dB and phase in two lines
20 * log|z| dB
arctan ( Im(z) / Re(z) )
Lin Mag and Phase
Magnitude of z (unconverted) and phase in two lines
|z|
arctan ( Im(z) / Re(z) )
Real and Imag
Real and imaginary part of z in two lines
x
y
Default (Trace)
Marker format identical with trace format
–
R + j X
Unnormalized resistance and reactance; L or C in three lines
(Smith diagram)
R
X
L or C**
)
G + j B
Unnormalized conductance and susceptance; L or C in three lines
(Inverted Smith diagram)
G
B
L or C**
)
*
)
The delay aperture is defined in the Trace – Format menu.
**
)
The equivalent inductances or capacitances L or C are calculated from the imaginary part of the
impedance according to