Operating Basics
AFG3000 Series Quick Start User Manual 47
You can select an internal or external signal as an AM source. If you select an external source and set the modulation
depth to 120%, the output will be at the maximum amplitude when a ±1 Vp-p signal is applied to the rear panel EXT
MODULATION INPUT connector.
You can select a modulation shape from the internal memory or USB memory.
The following equations show the output amplitude of AM, FM, and PM modulation (in this example, sine waveform is
used for carrier waveform and modulation waveform):
The following table shows relationship between modulation depth and maximum amplitude for AM modulation waveform
(internal modulation source is selected):
Carrier amplitude A [Vp-p]
Carrier frequency fc [Hz]
Modulation frequency fm [Hz]
Time t [sec]
AM Modulation depth M [%]
FM Deviation D [Hz]
PM Deviation P [degree]
Depth Maximum amplitude
120% A (Vp-p)
100% A (Vp-p) * 0.909
50% A (Vp-p) * 0.682
0% A (Vp-p) * 0.455
AM: Output(Vp-p)= A
2.2
-------- 1 M
100
----------2πfmt()sin+
⎝⎠
⎛⎞
2πfct()sin
FM: Output(Vp-p)=A 2πfc D 2πfmt()sin+()t()sin
PM: Output(Vp-p)=A 2πfct 2πP
360
----------2πfmt()sin+
⎝⎠
⎛⎞
sin