I'm working on an experiment which measures the response of a system to a 2-10 us long pulse sequence. The response is very deep in the noise and requires a lot of averaging of the response signal. The system recovers instantaneously after the pulse sequence, and thus we would like to repeat the pulse sequence as soon as possible. I'm struggling to find a signal averaging oscilloscope that's able to respond faster than 1 microsecond (FastFlight-2 signal averaging oscilloscope, not available anymore) after the end of a trace. We can't miss triggers, as a missed trigger means missed data, missed averages, and therefore longer to collect enough averages to obtain meaningful data. Does anyone have an idea for how to average a million or so repetitive segments of analog signal without losing data?
So what is the purpose, i.e. is this to take a snapshot (i.e. a few cycles) or is this for continuous monitoring?
Scopes are great for the former but pretty bad for the latter.
If you just want to record a number of cycles then I'd suggest you get a scope with very large sample memory. Ignore waveform rates, even the fastest scope will be blind for around 90% of the time so you need a scope that can capture the required sequence in one go. You need to decide how many cycles you want and then multiply with 4GSa/s and then you got the sample memory size you need.
I understand that the BW requirement is 1GHz, so yes you want at least 4GSa/s.
As to which scopes, forget any of the embedded scopes like the DSO-X, they don't have the memory sizes or capabilities to do what you need. Instead, I would look at the Keysight Infiniium-S DSO-S104. The DSO-S has the advantage of letting you not only select memory size but also sample rate, and it can be optioned up with large memory (536Mpts at
<5GSa/s in single-channel mode). I believe it also supports boxcar averaging, and if not it can optionally run MathLab scripts so you can do the averaging there.
However, if this is for continuous monitoring then I would just forget bench scopes and look into high speed digitizers, for example as PXI Express system. You can get the raw sample stream from your digitizer and feed it into Mathlab/Octave/SciLab/whatever to get your data.