So I was trying to use my limeSDR as a simple SNA to measure power responses of the filters we build, and I decided to use SoapySDR just because it is an easy way to make a portable (across SDRs) application. I got to grips with most of the API, but there is still this question that I’m kind of curious about is the pipeline latency. That is, how far in the future should I schedule the TX burst in order to be able to reliably receive it?
I’m using buffer size of 1 MTU and I schedule i MTU of TX ahead of time and then just start receiving. I found that if I schedule the TX burst 20ms in the future, they tend to come out pretty much when expected using lower sampling rates (below 20MSPS) and central frequencies (which is desired for my application), but when I try to schedule them earlier (that is - less far into the future) or go wider in Fs, the bursts tend to not get transmitted at all.
So I was curious if there was a reliable way to account for it in software prior to doing the measurements or should I adopt a different strategy like continuous RX instead of burst mode to minimize the acquisition time of my measurements?