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1 vote

Implementation of dispersion compensation of lamb waves

In order to help you I need you to expand the functions: get_velocity_at_freq(), wp.theoretical_group_phase_vel() that are not ...
Francisco Romero's user avatar
0 votes
Accepted

Finding zero input response with only one initial condition

Your solution is correct, but it's good to understand the reason why you only need one initial condition in this case: there are only two output values in the difference equation, and they are only ...
Matt L.'s user avatar
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6 votes
Accepted

For unit step $g(t) = u(t)$, why does $G(z) = \frac{z}{1-z}$, whereas $G(s) = \frac{1}{s}$?

Answer to the updated question: You wonder why there are several mappings from the continuous domain to the discrete domain, and why we don't just use the optimal mapping $z=e^{sT}$. Let's see how we ...
Matt L.'s user avatar
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0 votes

Scaling Property in DFT

But 1/ab is scaling the magnitude. Here limits are for the indices.
user70160's user avatar
0 votes

Finding Discrete Fourier Transform (DFT) for different DFT size

This exercise is aimed at showing that zero-padding in the time domain interpolates the frequency domain. Since this is homework, I'll give you the beginning of the solution. Just like you did, start ...
Jdip's user avatar
  • 5,137
0 votes

Implementing point-wise multiplication as a convolution

No, that's impossible. Simple consideration based on the neutral elements of "multiplying with"! The neutral element of right-hand multiplication is the constant 1-function, i.e. to make $p=...
Marcus Müller's user avatar
2 votes
Accepted

What is the rationale behind the "same" mode of discrete convolution?

I think that the only reason why the same mode exists is because sometimes it is convenient if the output has the same length as the input (assuming that the input ...
Matt L.'s user avatar
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1 vote
Accepted

Calculating the main lobe width of Dirichlet kernel

There's no analytical solution for the general case. However, it's quite straightforward to compute that value using a few iterations of Newton's method. I've done that and the plot below shows the ...
Matt L.'s user avatar
  • 88.8k
1 vote

Proper audio noise and artifact detection approach

That's a tough problem to solve. There are commercial solutions for this type of measurements (e.g. Audio Precision (ap.com), Listen, Inc. (https://www.listeninc.com/). They do an ok job but tend to ...
Hilmar's user avatar
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2 votes

Why does the griffin lim algorithm work?

Sound is just the combination of multiple sin waves at different frequencies and phases. These phases determine how those sin waves combine together, i.e. if frequencies are resonant or eliminate each ...
biendltb's user avatar
  • 121
0 votes

Why is the DC component of discrete fourier transform not the same as the signal's arithmetic mean?

The question you cite proofs this for Continuous Fourier Transform, your code however uses the Discrete Fourier Transform which has significantly different properties. The DFT is typically defined as $...
Hilmar's user avatar
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3 votes
Accepted

Why dft sine plot is so strange

There are two things you can try, depending on what you're aiming for. If you want to see a sharp peak at frequency $\omega = 1$, as in the code in your question, then you need to increase the DFT ...
MBaz's user avatar
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1 vote

Practical Implications of DFT Eigenvector Formulations

The unitary scaling convention for the DFT is identical in scaling with its inverse and preserves energy across the transform or inverse transform: $$ \begin{align} \mathcal{DFT}\Big\{x[n]\Big\} & ...
robert bristow-johnson's user avatar

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