Questions tagged [power-spectral-density]
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10 questions
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Spread spectrum question
I am doing some experimentation with spread spectrum with and the results are confusing me.
Here is the graph in question. All measurements are done using CISPR QPK detector with the same RBW and ...
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How can a signal be "below the noise floor"?
I don't understand how the phrase "a signal is below the noise floor" is to be interpreted.
If a signal stochastic process \$X(t)\$ and a noise stochastic process \$Y(t)\$ are added
$$ Z(t) =...
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Trouble Understanding the hardware filters used by my EEG amplifier
First of all, let me introduce myself: I am a clinical neurologist and in the last few weeks I am delving into EEG quantitative analysis. I deeply apologize for posting in an engineering community ...
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how can we find out normalized bandwidth using two-sided 3db Power spectral density?
If we have the given bandwidth
RF BW = 25e3;
Modulation order M = 8
Modulation index h = 1/4
overlap factor L = 2
...
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How to properly compute noise power spectral density?
I am confused about two different definitions of Power Spectral Density (PSD) that I have seen online.
The first comes from the National Instruments LabVIEW documentation (1):
$$
PSD = \frac{PS}{\...
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Image downsampling by a fraction
I need to downsample an image (bitmap image of a Spectrogram) by a fraction, N/D, (rational: ex 4/5). I understand that this can be done with resampling by 4 followed by decimation by 5. If this is ...
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How to properly take the discrete Fourier transform of a signal as well as calculate the power spectral density of the DFT?
I'm getting conflicting answers on how to properly represent a DFT and normalize the results as well as calculate the normalized PSD of the time series. For background, I typically work with voltage ...
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Random telegraphic noise and Lorentzian noise power spectral density
Following the example of the Lorentzian noise power spectral density shown above (ref), I would like to clarify the following:
In the first figure (labeled by (c)), May I please know why the constant ...
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RF channel noise interference calculation
I am trying to calculate how far a co-channel or noise source has to be from the primary channel, in this case a WiFi channel, for it not to interfere with the link performance.
This question takes ...
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Effect of Antenna and gain on PSD of a radio receiver
I have a cheap SDR receiver and today I was trying to measure the noise in the system.
I tried to disconnect the antenna and measure the power over the frequency range of the device. I also decided to ...
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