Measurement Basics
R&S
®
FSW-K7
41
User Manual 1173.9240.02 ─ 23
If the DUT inserts a gain or an attenuation in the measurement, this effect can be
reflected in the result display on the R&S
FSW. To reflect a power offset in the mea-
surement trace, change the
4.7.4.7
Coupling the Frequencies
As described in
Chapter 4.7.4.5, "Normalization"
on page 38, normalized measure-
ment results are very accurate
as long as the same settings are used as for calibration
.
Although approximate normalization is possible, it is important to consider the required
frequencies for calibration in advance. The frequencies and levels supported by the
connected signal generator are provided for reference with the interface configuration.
Two different methods are available to define the frequencies for calibration, that is to
couple the frequencies of the R&S
FSW with those of the signal generator:
●
Manual coupling
: a single frequency is defined
●
Automatic coupling
: a series of frequencies is defined (one for each sweep
point), based on the current frequency at the RF input of the R&S
FSW; the RF fre-
quency range covers the currently defined span of the R&S
FSW (unless limited by
the range of the signal generator)
Automatic coupling
If automatic coupling is used, the output frequency of the generator (source frequency)
is calculated as follows:
Offset
r
Denominato
Numerator
RF
Freq
Source
Equation 4-1: Output frequency of the generator
Where:
F
Generator
= output frequency of the generator
F
Analyzer
= current frequency at the RF input of the R&S
FSW
Numerator = multiplication factor for the current analyzer frequency
Denominator = division factor for the current analyzer frequency
F
Offset
= frequency offset for the current analyzer frequency, for example for frequency-
converting measurements or harmonics measurements
The value range for the offset depends on the selected generator. The default setting
is 0
Hz. Offsets other than 0
Hz are indicated by the "FRQ" label in the channel bar
Chapter 4.7.4.8, "Displayed Information and Errors"
Swept frequency range
The F
Analyzer
values for the calibration sweep start with the start frequency and end with
the stop frequency defined in the "Frequency" settings of the R&S
FSW. The resulting
output frequencies (
) are displayed
in the "External Generator" > "Measurement Configuration" for reference.
Receiving Data Input and Providing Data Output
