Rohde & Schwarz FPC1000, User Manual

Page: 140 / 291

Analog Demodulation
FPC1000
125
User Manual 1178.4130.02 ─ 02
Shows the total harmonic distortion.
The THD is the ratio of the harmonics to the fundamental and harmonics. All har-
monics inside AF spectrum are considered up to the tenth harmonic.
11.2 Frequency Configuration
Access
: "Freq"
Access
: "Setup" > "Config Overview" > "Frequency" (selected settings)
Remote commands to configure the frequency:
●
Chapter 13.12.2, "Frequency" , on page 241
The R&S FPC1000 can demodulate a signal only if the frequency of the carrier signal
is known. Therefore, you have to define the frequency of the carrier signal, before any
useful information about the signal is shown in the application.
The width of the captured signal (the "span") is defined by the
demodulation band-
width .
If you do not know the frequency of the carrier signal, you have to find it out. You can
do that, for example, by searching the frequency spectrum in the spectrum application
in the area where you assume that the carrier is located.
Frequency settings in the analog modulation application described elsewhere:
●
"Center Frequency": "Defining a center frequency" on page 73
●
"Frequency Step Size": "Defining a frequency step size" on page 73
11.3 Amplitude Configuration
Access
: "Ampt"
Access
: "Setup" > "Config Overview" > "Amplitude" (selected settings)
Remote commands to configure the amplitude:
●
Chapter 13.10.3, "Amplitude" , on page 191
Amplitude settings in the analog modulation application described elsewhere:
●
"Reference Level": Chapter 9.4.1, "Reference Level" , on page 78
●
"Preamplifier": "Preamplifier" on page 82
●
"Attenuator": "RF attenuator" on page 80
●
"Impedance": "Selecting the input impedance" on page 77
When you select the graphical result display, you can also adjust the scale of the y-
axis.
Amplitude Configuration
北京海洋兴业科技股份有限公司（证券代码：839145） www.hyxyyq.com