Dears,
I have the opportunity to play with the SSA3032X-R device.
I'm using my Siglent SDG6022X AWG to play arround with QAM IQ Signals.
In order to make some tests with the dmod utility of the SSA3kX-R
I have used a QAM64 signal with center at 100MHz and 300ksps.
The SDG6kX generates a fixed message length of 4096 patterns.
But when setting the SSA to different message lengths (128, 256, 512, 1024, 2048, 4096)
I see a significant increasing error rate (EVM%) with the increase
of the message length that I could not fully understand.
perhaps someone can give me some explanation on this issue.
I would expect the same error rate when the IQ signal is of a stable
quality.
So in this specific case my question is if I'm wrong and have to adapt
my QAM knowledge or did the SDG or SSA or both have some issues
in generating or/and demodulating the QAM signal.
For better understanding I attached the SDG 64QAM Setting as well as
the screenshots for the 128 - 4096 of the SSA while demodulating.
The stat values where reseted after message length change.
Many thanks for your explanation in advance.
Markus