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May 1, 2022 at 13:01 history bumped CommunityBot This question has answers that may be good or bad; the system has marked it active so that they can be reviewed.
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Aug 4, 2021 at 11:08 answer added Hilmar timeline score: -1
Aug 4, 2021 at 9:16 history edited OverLordGoldDragon CC BY-SA 4.0
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Aug 4, 2021 at 9:16 comment added OverLordGoldDragon @Hilmar Right, I missed conjugation, which does return energy at origin.
Aug 3, 2021 at 14:30 comment added Hilmar But than it's not an autocorrelation. It's something else.
Aug 3, 2021 at 3:18 comment added OverLordGoldDragon @Hilmar $r_{xx}(T) = \sum x[n]x[n+T]$ is the definition I use (and is the standard w/ normalization) which differs from $|x...|$ for complex $x$.
Aug 3, 2021 at 3:08 history edited OverLordGoldDragon CC BY-SA 4.0
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Aug 2, 2021 at 22:23 comment added Hilmar Sorry, I'm not getting this. The autocorrelation can't be 0. $r_{xx}(0) = \sum |x[n]|^2$ so it's the power of the signal.
Aug 1, 2021 at 23:05 comment added OverLordGoldDragon Correction: zero autocorrelation (asm. zero-mean), or conv with own conjugate.
Aug 1, 2021 at 22:19 comment added OverLordGoldDragon @Hilmar Interesting article. I intend "analytic" in discrete/finite sense: negative DFT bins = zero. This guarantees zero in self-convolution.
Aug 1, 2021 at 21:51 comment added Hilmar @OverLordGoldDragon: can you give a crisp definition of what exactly you mean by "analytic sequence". The standard definition of a continuous analytic signal is "has no negative frequencies" but since a discrete signal is periodic in frequency, that doesn't work. Related reading: andrewduncan.net/air
Aug 1, 2021 at 20:14 history edited OverLordGoldDragon CC BY-SA 4.0
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Aug 1, 2021 at 20:14 comment added OverLordGoldDragon @PeterK. I seek to "qualify" $x$ for zero autocorrelation by only looking at it in time domain. Possible I'm missing something but I've not found much in Hilbert transform as aid; sure one can test x == analytic(x.real), but that doesn't reveal any properties like symmetry/norm. I suppose my actual goal is sufficient criteria for $A \neq B$.
Aug 1, 2021 at 18:01 comment added OverLordGoldDragon @PeterK. I'm unfamiliar with time-domain form of Hilbert transform, but suppose I'll find insights there - will look into. Also I'm uncertain regarding criterion 1, might be L1 norm instead, and unsure if there's such a relation for $A \neq B$; I'll revisit bit later.
Aug 1, 2021 at 17:48 comment added Peter K. Interesting question. What's wrong with the usual "the imaginary part is the Hilbert transform of the real part" ? It doesn't explicitly go to the frequency domain, though perhaps that implies something in the frequency domain.
Aug 1, 2021 at 17:33 history edited OverLordGoldDragon CC BY-SA 4.0
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Aug 1, 2021 at 17:24 history edited OverLordGoldDragon CC BY-SA 4.0
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Aug 1, 2021 at 17:15 history edited OverLordGoldDragon CC BY-SA 4.0
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Aug 1, 2021 at 17:07 history asked OverLordGoldDragon CC BY-SA 4.0