RIGOL DG5000 Series - Manual (Page 117)

Chapter 6 Frequency Sweep Output RIGOL
User’s Guide for DG5000 6-5
Log Sweep
The output frequency of the instrument varies in a logarithmic fashion, that is, the
output frequency changes in the way of “octave per second” or “decade per second”.
The change is controlled by “Start Frequency”, “End Frequency” and “Sweep Time”.
When Log Sweep is enabled, users could set the following parameters:
Start Frequency
start
F
, End Frequency
stop
F
and Sweep Time
sweep
T
The function prototype of Log Sweep is T
current
P F
= . P and T could be expressed by
the above-mentioned parameters:
sweep start stop
T F F
P
/ ) / lg(
10
=
) lg( / ) lg( P F t T
start
+ =
Where, t is the time from the start of the sweep and its range is from 0 to
sweep
T
.
current
F
is the instantaneous frequency of the current output.
When Sweep is enabled, press SwpType to select “Log”. In the Graphic Mode, an
exponential function curve, which indicates the output frequency changes in a
logarithmic mode, will appear on the screen (shown in the figure below).