Rohde & Schwarz R&S SMB100B - Page 123

List and sweep mode
R&S
®
SMB100B
123User Manual 1178.3711.02 ─ 08
Variable Description
f
2
Next, subsequent sweep frequency
step_lin Step size in linear scaling
step_log Step size in logarithmic scaling
POINts Number of steps within the sweep range
Sweep range
The sweep range is defined by a start and an end value. How the remaining parame-
ters correlate is shown below.
Offset = 0
Sweep Range = f
STARt
to f
STOP
f
CENTer
= (f
STARt
+ f
STOP
)/2
f
SPAN
= (f
STOP
- f
STARt
)
Where:
f
STARt
= f
CENTer
- (f
SPAN
/2)
f
STOP
= f
CENTer
+ (f
SPAN
/2)
Offset≠0
A defined offset also affects the sweep range and the center frequency. Therefore, the
set frequencies are only absolute values, if the Offset = 0. Offset ≠ 0 shifts the frequen-
cies with the offset value:
Sweep Range = f
STARt
+ f
OFFSet
to f
STOP
+ f
OFFSet
f
CENTer
= f
CENTer
+ f
OFFSet
f
SPAN
= f
SPAN
+ f
OFFSet
The value range of the instrument is calculated as follows:
RF
min
+ f
OFFSet
to RF
max
+ f
OFFSet
It is possible to set f
STARt
> f
STOP
and f
STARt
< f
STOP
, so that even a negative value is per-
mitted for the "Span".
If you change the start and/or stop frequency, the span and center frequency change
accordingly, and vice versa.
Sweep steps
In the following, you see how the sweep steps are calculated depending on the defined
spacing mode. The formulas show a frequency sweep, but apply to the level settings in
the same way.
The step size is added to the current value, to get the subsequent sweep step.
About sweep mode