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lneuhaus / pyrpl

pyrpl turns your RedPitaya into a powerful DSP device, especially suitable as a lockbox in quantum optics experiments.
http://lneuhaus.github.io/pyrpl/
MIT License
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na transfer function systematically underestimated by 0.35 db? #269

Open lneuhaus opened 7 years ago

lneuhaus commented 7 years ago

... or by a 4% error in amplitude.

lneuhaus commented 7 years ago

this only happens at very small amplitude and gradually disappears when amplitude is increased -> should nevertheless try to correct for this by properly modeling ampltidue

lneuhaus commented 7 years ago

did properly model amplitude, but mismatch is still there for small amplitudes -> another roundoff thing because we only implement approximations to rounding in fpga -> leaving this open as a reminder to implement correct rounding in all fpga computations in the next release...