Forums › BB Series Discussions › BB60D API decimation CPU usage
- This topic has 2 replies, 2 voices, and was last updated 1 month ago by BEged.
- AuthorPosts
BEgedParticipant- This topic was modified 1 month, 3 weeks ago by BEged. Reason: hello, regards
Hello Support Team,
We currently use BB_API Version 5.0.6 (6/22/2023), which provides a way to configure the device for IQ streaming by way of bbConfigureIQ. In our use case, the IQ stream we take out of the API has multiple consumers with differing needs, meaning that we already do our own filtering and decimation downstream, with multiple differing sets of parameters.
This in turn means that we take the lowest common denominator form of the stream out of the API, which happens to be the full 40MS/s stream without any decimation whatsoever. Our problem is that the API already does its own filtering and decimation, even in the case of the largest bandwidth setting, using valuable CPU resources that we would like to spend elsewhere.
This has us wondering whether you might consider extending the API such that it would allow taking out IQ streams without any preceding processing whatsoever. Something along the lines of bbConfigureIQRaw(int device).
We realize that this would affect the frequency domain structure of the stream (e.g. it might be a 80MS/s real sample stream instead, with a center frequency that is a complex function of other streaming parameters), but as we do our own processing downstream anyway, we could just absorb whatever we need to deal with that into those downstream processing tasks.
Regards,
Justin CrooksModeratorAbout 10 years ago, we offered raw IF output. The challenge is that without corrections, the data is not very useful for most tasks. And those corrections are built from real-time temperature data. We don’t have any IP for generating these after the fact. It ends up being a pretty big filter to compensate for the IF SAW filter ripple.
Long story short, we recommend using a CPU with a bit more horsepower, rather than trying to get around the real-time processing.
You could also look at the SP145, which has a much lower CPU load when streaming.
BEgedParticipantThank you for your response. This aligns well with what we assumed, but we felt it was best to ask anyway. More horsepower or better RF HW it is, then.
Regards,
- AuthorPosts
You must be logged in to reply to this topic.