R&S SMA100B - User Correction

Improving level performance
R&S
®
SMA100B
221User Manual 1178.3834.02 ─ 09
4. Set "Required Generator Level", e.g. "20 dBm" to configure the maximum power
level at the RF output.
This value corresponds to the losses of cabling and coupler to compensate.
5. In the "RF Level" tab, select "Readjust " to execute the instrument detector offset
compensation.
This function recalculates and compensates the internally detected offset voltages.
6. Set "RF" > "State" > "On".
After turning on the RF output, the system levels the coupler output power to the
value set in the instrument level display
8.3 User correction
The R&S SMA100B supports a correction function to compensate external losses,
caused, for example, by the RF cable, to achieve a precise target input level at the
DUT.
The signal at the RF outputs of the R&S SMA100B is flat. However, the DUT is usually
not connected directly to the outputs of the instrument but rather via connecting cables.
Components like cables, power combiners, switches or mixers can affect the signal
flatness at the DUT input.
Figure 8-2: Effect of external losses on the signal flatness at the DUT input
DUT = Device under test
Components = Designation of all components between the measurement equipment and the DUT, e.g.
cables
1 = Flat signal at the outputs of the R&S SMA100B
2 = Signal received at the DUT, incl. the external losses
About UCOR
User correction (UCOR) is a method that determines the external level loss over a fre-
quency range in advance, see Figure 8-3.
The difference between the generator output level and the level at the DUT determines
the correction value at the respective frequency. Alternatively, the attenuation charac-
teristics over a certain frequency range of, for example, RF cables are also specified in
the associated data sheet.
User correction