Rigol DG1000Z Series - Center Frequency and Frequency Span

RIGOL Chapter 2 Front Panel Operations
2-58 DG1000Z User’s Guide
Center Frequency and Frequency Span
You can also set the frequency boundaries of frequency sweep through center
frequency and frequency span.
 Center Frequency = (|Start Frequency + Stop Frequency|) / 2
 Frequency Span = Stop Frequency – Start Frequency
When sweep mode is enabled, press Start/Center to highlight “Center”. Notice
that the “Span” in Stop/Span will also be highlighted at the same time. Use the
numeric keyboard or direction keys and knob to enter the desired frequency values.
By default, the center frequency is 550Hz and the frequency span is 900Hz. Different
sweep waveform corresponds to different center frequency and frequency span
range and the center frequency and frequency span are interrelative.
Define the minimum frequency of the waveform currently selected as
min
F
, the
maximum frequency as
max
F
and
2/)(
maxmin
FFF
m
+=
.
 The range of center frequency is from
min
F
to
max
F
and the parameters for
different waveforms are as follows.
Sine: 1μHz to 60MHz
Square: 1μHz to 25MHz
Ramp: 1μHz to 1MHz
Arb: 1μHz to 20MHz
 The range of frequency span is influenced by the center frequency.
Center frequency <
m
F
: the range is ±2× (center frequency –
min
F
);
Center frequency ≥
m
F
: the range is ±2× (
max
F
– center frequency).
Take sine as an example.
min
F
is 1μHz,
max
F
is 60MHz and
m
F
is about 30MHz.
If the center frequency is 550Hz, the frequency span range is ±2×(550Hz–1μHz) =
±1.099999998kHz; if the center frequency is 55MHz, the frequency span range is
±2×(60MHz–55MHz) = ±10MHz.
The generator will renewedly sweep (according to the current new configuration)
from the specified “start frequency” after center frequency” or frequency span is
changed.
TIP:
In large-scale sweep, the amplitude characteristic of the output signal might
change.