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3 votes

Design of digital filters with negative group delay

Here is another version. This is a tricky problem. Allpass filters clearly don't work here since the have a strictly monotonic decreasing phase, so the group delay is always positive. That means the ...
Hilmar's user avatar
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1 vote

Design of digital filters with negative group delay

The analog filter you came up with exemplifies the problem that one usually encounters when designing filters with negative group delay in a certain frequency band. The filter with transfer function $...
Matt L.'s user avatar
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0 votes

Resolution after Oversampling, Filtering-Decimation

You don't know enough. There's two absurd extremes: first, you could have an ADC that has no thermal noise at all, but distortion that's 108.51dB below the ADC's full-scale input range; second, you ...
TimWescott's user avatar
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0 votes

Resolution after Oversampling, Filtering-Decimation

Your calculations are correct. Of course using an over-sampling factor of 256 will reduce the bandwidth of your converter by the same amount. Note that oversampling only improves the SNR if the ADC ...
Bob's user avatar
  • 548
3 votes
Accepted

low shelving filter frequency response diagnosis

Your filter coefficients and your difference equation are wrong. You assumed that the output signal $y[n]$ is fed back to the input, but what is actually fed back is the signal before the multiplier $...
Matt L.'s user avatar
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2 votes
Accepted

group delay of Bessel filters

The group delay $\tau(\omega)$ of a Bessel filter equals $1/\omega_0$ at $\omega=0$, where $\omega_0$ is the normalization frequency. It is independent of the filter order, unless we choose different ...
Matt L.'s user avatar
  • 89k
0 votes

Basic tools for digital filter design?

There are also some interesting on-line tools that can be used to design the filter and obtain the filter coefficients. These can be copy-pasted to the code and then be used to implement the desired ...
Filipe Pinto's user avatar
0 votes

How to design IIR digital filters?

Despite previous commenters decrying the design method, I found an interesting online tool at https://www.micromodeler.com which satisfies the questioner's requirement of manual placement of poles &...
Nigel Winterbottom's user avatar
0 votes
Accepted

Problem by designing and filtering a Bessel-Thomson filter in Python

You can approximate or simulate an analog signal, but it lives inside your computer, so by definition is digital. You can only filter a digital signal using a digital filter. If you’re only interested ...
Jdip's user avatar
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2 votes
Accepted

Allpass Filter with Sign Switch

In this answer I'll just focus on the given design problem, even though I'm not sure if there might be a better overall solution to your underlying problem. First of all it's instructive to realize ...
Matt L.'s user avatar
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