58
Operator’s Manual Simple AFG Application
Berkeley Nucleonics Corporation
[email protected] | www.berkeleynucleonics.com
2955 Kerner Blvd, San Rafael, CA 94901 | 800-234-7858
Rev 1.1
Marker out (blue, top) synchronous with the modulating waveform of the AM (red, bottom) in Manual width mode
Modulation General Parameter
•
Frequency [Hz]:
it defines the modulating frequency. It can vary between 500uHz and 61MHz.
•
Source:
the source can be
Internal
or
External
. If
Internal
is selected it is possible to select a
Shape. If
External
is selected the instrument accepts a modulating signal from the
Ext. Mod.
SMA input connector.
Modulation Types and associated parameters
•
Amplitude Modulation (AM):
the amplitude of the carrier waveform is modulated following the
modulating shape. It is available for all functions except for the Pulse, Double Pulse, DC level and
Noise.
The parameter
Depth [%]
controls
the modulation depth between 0% and 120%.
•
Frequency Modulation (FM):
the frequency of the carrier waveform is modulated following the
modulating shape. It is available for all functions except for the Pulse, Double Pulse, DC level and
Noise.
The parameter
Deviation [Hz]
defines the frequency deviation with respect to the carrier
frequency. The Deviation is between 0 Hz and the maximum frequency that satisfies the
following 2 relationships:
-
𝐶𝐶𝐿𝐿𝑇𝑇𝑇𝑇𝐿𝐿𝐿𝐿𝑇𝑇
𝐹𝐹𝑇𝑇𝐿𝐿𝐹𝐹𝐹𝐹𝐿𝐿𝐿𝐿𝐹𝐹𝐹𝐹 − 𝐷𝐷𝐿𝐿𝐷𝐷𝐿𝐿𝐿𝐿𝑊𝑊𝐿𝐿𝑃𝑃𝐿𝐿
> 0
𝐻𝐻𝐻𝐻
-
𝐶𝐶𝐿𝐿𝑇𝑇𝑇𝑇𝐿𝐿𝐿𝐿𝑇𝑇
𝐹𝐹𝑇𝑇𝐿𝐿𝐹𝐹𝐹𝐹𝐿𝐿𝐿𝐿𝐹𝐹𝐹𝐹
+
𝐷𝐷𝐿𝐿𝐷𝐷𝐿𝐿𝐿𝐿𝑊𝑊𝐿𝐿𝑃𝑃𝐿𝐿 ≤ 𝑀𝑀𝐿𝐿𝑀𝑀𝐿𝐿𝑀𝑀𝐹𝐹𝑀𝑀
𝐹𝐹𝑇𝑇𝐿𝐿𝐹𝐹𝐹𝐹𝐿𝐿𝐿𝐿𝐹𝐹𝐹𝐹
Where the Maximum Frequency depends on the selected carrier.
For example, for a sine function at 200 MHz the Deviation must be below 200MHz.
•
Phase Modulation (PM):
the phase of the carrier waveform is modulated following the
modulating shape. It is available for all functions except for the Pulse, Double Pulse, DC level and
Noise.
The parameter
Deviation [deg]
specifies the maximum phase deviation of the carrier waveform.
It can vary in the range 0 to 360 degrees.
