I have a really simple question that I can't seem to find the answer to online (and pardon my limited signal processing background). I'm trying to help a fellow colleague figure out a processing problem.
An external code modulates a real-valued signal that is eventually fed into GRC. For now the signal is generated with some arbitrary positive center frequency and then a GRC script converts it to complex and then downshifts and centers it at 0Hz. This isn't efficient because the modulation in the external code takes a lot longer with higher sampling frequency.
If the external code was modified to put the real-valued signal in the -5 to 5kHz band (centered at 0Hz and assuming a real-valued signal can represent negative frequencies), is the minimum sampling frequency to avoid aliasing 20kHz or is it 10kHz? This is before the GRC
script converts it to complex.
Thank you in advance.. Tom
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