11 questions linked to/from Why so many methods of computing PSD?
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### From FFT to PSD using Pwelch Matlab [duplicate]

I am trying to understand the difference between FFT magnitude and PSD (Power spectral density) with pwelch function of Matlab. In my example, Val1 and Val2 will output the same thing? ...
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### In a periodogram, why is the modulus squared of the DFT taken rather than the DFT itself? [duplicate]

Why can't you just take the DFT itself? And how accurate is this method in spectral density estimation? Are there cases in which it is very accurate?
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### Estimating a Power Spectrum from a Time Series [duplicate]

What are the best ways to estimate the power spectrum of a given time series? Any pointers to review articles or book chapters would be appreciated. A little more information: When estimating a ...
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### How to get PSD from frequency domain representation of time-series data [duplicate]

Let's say we have a realization (time-series data) of a random process. I take fft() of that to get its frequency domain representation. Then how can I estimate the PSD of this random process by ...
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### What is the difference between PSD and squared magnitude of frequency spectrum?

The power spectrum of a signal can be calculated by taking the magnitude squared of its Fourier transform. Being an audio person, the signal of interest for me would be a time series. How does this ...
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### Why is PSD estimated, and not simply computed?

I apologize if this comes as a basic question, but I am struggling to understand why the PSD can only be estimated and not directly computed. For example, this thread discusses several such PSD ...
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### Smoothing a power spectrum

My question is regarding how one could/should smooth a rather noisy power spectrum obtained from measurements. There are various methods one can use (a moving average, binning, etc) and I am not sure ...
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### What is the computational complexity of Spectrum Estimation Algorthms and What they depend upon?

There are lots of spectrum estimation techniques, each with some pros and cons. Algorithms like: Music Welch's method Yule-Walker AR method Periodogram modified covariance method multitaper method (...
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### Is it appropriate to use PSD on the analysis of a plucked guitar string?

I'm using python 2.7 to compare tonal differences in guitar stings. I've found that in matplotlib, there are some great built-in features such as matplotlib.mlab.magnitude_spectrum and matplotlib....