Questions tagged [signal-processing]
The subfield of electrical engineering that focusses on analysing, modifying, and synthesizing signals such as sound, images, and scientific measurements.
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Why the $T_1$ recovery & $T_2$ decay are independent?
In MRI, I was thinking that the decrease in transverse magnetization results in the recovery of longitudinal magnetization.
However, recently, I found it was wrong. I saw a diagram
(McRobbie 2014. ...
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How exactly does a seashell make the humming sound?
My little brother asked me where the ocean-like sounds came from inside of a sea shell. I told him that the air trapped inside the shell vibrates, making a sound. But then he asked me why the air had ...
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Weird looking sine wave behavior in an electric circuit
while studying an RLC circuit I noticed some weird like sine waves at low frequencies (1-9 kHertz) on the inductor,
The amplitude behavior did not follow the theoretical model. Instead, suggested the ...
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What does "DC" mean in gravitational physics?
I have came across a few works in gravitational physics using the term "DC" without further explanation of its meaning. For example, consider Strominger's 1703.05448, which states in p. 2 ...
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How to solve the transient response of a general $RLC$ network?
There is a $RLC$ network $\{V_i\}$ with a complex impedance $Z_{ij}$ on each edge. all vertices have initial voltage $V_i$ and all edges have initial current $I_{ij}$. Now, is there a general way to ...
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How can I determine an error on total noise?
I am analyzing the data for an experiment, where we measured the total noise in a system. The total noise is defined as the variance of the signal (and is equal tot the integral over the noise ...
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Fourier Transform of periodic Signals
If $f(x)$ is a periodic signal with a period $A$ then the Fourier transform of the signal $F(k)$ is zero, unless $k A$= $2 \pi n$ where $n$ is an integer. How can there Be a Fourier transform of a ...
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Is there a name for the number of '9's in numbers such as 0.999 (where it would be 3)?
I am doing an optics simulation involving transmission and reflection coefficients very close to 1, such as 0.999. While I was an undergraduate student, a professor mentioned that, in certain fields, ...
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Feynman claimed "The ear is not very sensitive to the relative phases of the harmonics." Is that true?
In The Feynman Lectures on Physics, Dr. Richard Feynman claimed that the ear (I assume he meant the human ear) is not sensitive to the relative phases of harmonics.
However, I was asked to test ...
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Phase-Based Ranging
I've been reading a lot about Phase-Based Ranging (PBR), and it's all starting to become very intuitive.
BUT; There is one technical, but extremely important, detail that seems to escape me. When the ...
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How to extract the "matter fluctuation amplitude" from the CMB power spectrum?
How do you convert the value listed in Planck 2018 results. VI. Cosmological parameters, $A_s = 2.101\times10^{-9}$ to the value of the matter fluctuation amplitude $\sigma_8=0.8111$? I tried ...
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Signal recovery limits, magnetic
This question is about signal recovery. I am interested in what is the best that has been done so far, in the case of a signal of known form and which is not simply a sine wave, and what might in ...
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What relationship between the time recording length and the frequency bandwidth?
In model testing for ocean waves, the data recording duration is usually longer the better especially for irregular waves. The recording length shall be long enough to achieve sufficiently small ...
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I don't understand intuitively why the instantaneous frequency is obtained by calculating the time derivative of the phase
I don't understand intuitively why the instantaneous frequency is obtained by calculating the time derivative of the phase
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Does sunlight have a modulation frequency?
By frequency, I don't mean electromagnetic frequency, I mean modulation frequency. For example, I can put a PWM square wave on an LED at some frequency, which I can detect with a photodiode and a ...
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