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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"Synchronization" Probability of Multiple Waves with Varying Frequencies
Update 1: I've done some digging and I think this is related to signal coherence, namely, that I'm seeing a coherence time of ~3 σ, which is consistent with the definition where Ct=1/Δv where Δv is ...
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The frame of truncated momentum basis on a 1D lattice
$\def\ket#1{\left|#1\right\rangle }
\def\bra#1{\left\langle #1\right|}$
(This is part of a research problem)
The Setup:
Consider a single particle on a finite 1D lattice with the Hilbert space ...
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Mathematical term for the on/off gradient functions in MRI imaging
The slice selection gradients, as well as the phase and frequency, in MRI imaging are traditionally represented by on/off box or rectangular symbols:
or
My question is what is the mathematical name ...
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Is it possible to estimate the number of people in a room from a limited number of simultaneously recorded audio samples?
Note: I struggled to decide the appropriate site for this question, between https://physics.stackexchange.com/, https://video.stackexchange.com/, https://math.stackexchange.com/, and even https://...
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Effect of Background Radiation on a Transmitted Signal
I'm coding a basic simulation of using error correcting codes to transmit data from a satellite back to earth. I'm not sure what to set the "noise level" to. Let's say a satellite orbiting Mars ...
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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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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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How to interpret doppler curve images of Chandrayaan-2 lander?
The frequency transmission data for Vikram, lander of Chandrayaan-2, received by 25 meter Dwingeloo radio telescope is plotted and tweeted by Cees Bassa. Kinks in the Doppler curve are interpreted as ...
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The validity of some "applications" of the uncertainty principle
Given a $L^2$ function $f$ with $\int_\mathbb{R}xf(x)dx=0$, define its variance to be $\sigma_f^2=\int_{\mathbb R}x^2f(x)dx$. The uncertainty principle states that $\sigma_f\sigma_\hat f\geq 1/4\pi$,...
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Why is the optimum window length for a discrete fourier transform of a signal less than 100%?
I'm trying to determine the best settings for a discrete Fourier transform on a signal with noise. Now I've stumbled on something that I can't seem to explain, I'm hoping someone can give me some ...
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Is LIGO designed as a bandpass instrument?
This question intended for those that may have personally worked on LIGO and are knowledgeable about its detailed systems architecture.
I understand that LIGO basically uses a Michelson-Morley type ...
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Converting (time domain) Fluctuations to Power Spectral Density (PSD)
I have a Voltage signal, $V$, with fluctuations that go as:
$$
\langle\delta V(\tau)^2\rangle=\ln f_a\tau
$$
Here $f_a$ is an attempt frequency from an Ahrennius Law. According to many papers, "...
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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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Two-Ray Ground-Reflection Model: Understanding the Difference in Phase Offsets at the Receiver
Currently, I'm trying to understand the Two-Ray Ground-Reflection Model.
During my research, I came across the following simplification expressing the received power as follows (taken from Wikipedia):
...
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Modeling an Acoustic Reflection from a Wall
I am trying to simulate the reflection of a sound ray, that goes from a sound source, bounces off a wall, and is received by a microphone.
The wall has a an absorption coefficient, and a specular ...
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