New answers tagged power-spectral-density
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How do you find the null to null bandwidth for the signal below?
The $\text{sinc}$ function is the Fourier Transform of a Rectangular pulse.
Its zeros are located at non-zero integers of $x$.
Therefore, if your spectrum can be expressed as $\text{sinc}(Bx)$, the ...
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How do you find the null to null bandwidth for the signal below?
The key observation is that $\text{sinc}(x)$ is zero for all arguments $x$ that are nonzero integers, so the problem reduces to "what values of $f$ yield the nonzero integers closest to zero, ...
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How do you find the null to null bandwidth for the signal below?
The following MATLAB script is a solution to your question
clear all;close all;clc
1. fzero only returns 1 zero
...
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How to plot in MATLAB the PSD of two signals with different bandwidths
The spectrum of a BPSK signal has a sinc function envelope. That's not bandlimited and falls off very slowly with frequency so you can't easily sample it without getting significant amount of aliasing ...
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Why power = variance = rms^2 in the White Noise process?
I saw the article variance = power = rms^2 in White noise.
That's true for almost all mean-free signals, not just white noise. For simplicity, we assume a discrete real signal, $x[n]$ of length $N$ ...
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Why power = variance = rms^2 in the White Noise process?
The relationship between variance and rms value follows directly from the definition of variance. For a continuous random variable, it is defined as:
$$
\sigma^2 = E\left(\left(X - \mu\right)^2\right)
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Where does the following expression for stationary Gaussian Noise come from: $\langle \tilde{n}(f)\tilde{n}(f')\rangle = \delta(f-f')\frac{1}{2}S_n$?
From Probability, Random Variables, and Stochastic Processes, A. Papoulis, McGraw-Hill 1984, p. 306:
If the process $\mathbf x(t)$ is WSS with power spectrum $S(\omega)$ then its transform $\mathbf X(...
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Does the resolution of a timeseries affect the estimate of the power-spectrum when using np.fft.rfft and does it comply with parseval's theorem?
The second method has the correct scaling (divide by $Nf_s$) for a Power Spectral Density.
However, that scaling won't work to verify Parseval's result, since its units are Power/Hz.
Your 1st method, ...
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