Rohde & Schwarz 1145.1010.04/05/06, Operating Manual

Page: 224 / 813

Trace Menu R&S
®
ZVA/ZVB/ZVT
1145.1084.12 4.62 E-6
the frequency domain.
Use the paste marker list for convenient entry of Start and Stop values.
Distance units for transmission and reflection parameters
The interpretation of time and distance depends on the measurement type. For reflection
measurements, the time axis represents the propagation time of a signal from the source to the DUT
and back. For transmission measurement, it represents the propagation time from the source through
the device to the receiver. The
Distance calculation is consistent with this interpretation:
•
For reflection measurements (S-parameters S
ii
or ratios with equal port indices) the distance
between the source and the DUT is half the propagation time multiplied by the velocity of light
in the vacuum times the velocity factor of the receiving port defined in the
Channel – Offset
menu (Distance = 1/2 * Time * c
0
* Velocity Factor) . The factor 1/2 accounts for the return trip
from the DUT to the receiver.
•
For transmission measurements, the distance is calculated as the propagation time times the
velocity of light in the vacuum times the velocity factor of the receiving port defined in the
Channel – Offset menu (Distance = Time * c
0
* Velocity Factor) .
Due to the properties of the Chirp z-transformation the trace is periodic in time and repeats after
an unambiguous range of t = 1/ f. where f is the spacing between two consecutive frequency points.
To extend the unambiguous range, either reduce the sweep span (
Channel – Stimulus ) or increase the
number of sweep points.
Remote control:
CALCulate<Ch/Tr>:TRANsform:TIME:STARt
CALCulate<Ch/Tr>:TRANsform:TIME:STOP
CALCulate<Ch/Tr>:TRANsform:TIME:CENTer
CALCulate<Ch/Tr>:TRANsform:TIME:SPAN
CALCulate<Ch/Tr>:TRANsform:TIME:XAXis TIME | DISTance