R&S SMJ100A, Operating Manual, Page: 385 / 874

Instrument Function
R&S
®
SMJ100A
369 Operating Manual 1403.7458.32 ─ 14
ARB Test Signals
The following test signals are available:
●
Sine Test Signal: Two sinewave signals with a selectable (but equal) number of
samples per period and equal frequencies. When the generation is triggered, the
number of samples per period, together with the frequency of the test signal, deter-
mines the ARB clock frequency: "Clock Frequency" = "Frequency" * "Samples per
Period".
Note: Because the resulting clock rate must not exceed the maximum ARB clock
rate (see data sheet), the number of sample values is automatically restricted
depending on the selected frequency.
The first sine signal is mapped on the I samples, the second on the Q samples.
The two signals differ by a selectable phase offset. For a
–
90 deg offset, the result
is a unit vector in the I/Q plane, rotating counter-clockwise and starting at I = 0, Q =
–
1. For a 0 deg offset, the I and Q samples are on the diagonal of a unit square (I(t)
= Q(t)).
In general the I/Q samples are located on a deformed circle which is confined to
the dashed square in the upper diagrams.
●
Rect Test Signal: Rectangle signal with selectable but equal On and Off periods
and amplitude. The period is defined by the selected frequency: <Period> = 1 /
"Frequency".
The signal is mapped on both the I and Q samples. This results in two distinct
points in the I/Q plane. The "Offset DC" shifts both points along the diagonal I(t) =
Q(t).
Baseband Signal - Baseband Block