Linked Questions
20 questions linked to/from Why Hilbert Transform is terrible choice for amplitude demodulation of broadband signals?
2
votes
1
answer
1k
views
Envelope by using Hilbert not working in python [duplicate]
I'm trying to obtain the envelope of an audio signal by using the Hilbert method. My code generates the analytical signal in the same way as scipy.signal Hilbert() function does (I basically copied ...
- 23
23
votes
2
answers
13k
views
Synchrosqueezing Wavelet Transform explanation?
How does Synchrosqueezing Wavelet Transform work, intuitively? What does the "synchrosqueezed" part do, and how is it different from simply the (continuous) Wavelet Transform?
- 9,242
12
votes
3
answers
3k
views
What information does the Hilbert transform give?
The Hilbert transform of a function is defined as :
$$\mathscr{H}\big\{f(t)\big\} = \lim_{T\rightarrow \infty}\frac{1}{\pi}\int\limits_{-T/2}^{T/2}\frac{f(\tau)}{t-\tau}\, \mathrm{d}\tau$$
Okay but ...
- 305
4
votes
1
answer
2k
views
How to find the envelope of a wide-band signal?
I would like some feedback on possible techniques that one may use to determine the envelope of a broad-band time domain signal. I have heard anecdotally, that it is not as straight-forward as it ...
- 9,897
4
votes
1
answer
2k
views
Conditions for which the Hilbert transform returns a correct phase
I'm quite new to signal analysis, and I'm currently trying to understand under which conditions a Hilbert transform can be used to compute the correct instantaneous phase and enveloppe of a given ...
- 43
3
votes
1
answer
2k
views
Envelope detection using hilbert transform
I have a sine wave of frequency 1kHz sampled at 16kHz. I need to find the envelope of this signal using hilbert transform in MATLAB.I have used the inbuilt function abs(hilbert(input_signal)) and got ...
- 325
3
votes
2
answers
1k
views
Amplitude extraction using STFT
I'm trying to recover amplitude/magnitude from an audio stream. I'm using FFT to go from time domain to frequency.
If I feed in a signal of known amplitude, the results I get from either windowing or ...
- 253
3
votes
5
answers
2k
views
How to calculate the instantaneous frequency of a signal?
I am trying to do the complex trace analysis of a seismic trace in Matlab where I need to calculate the instantaneous frequency of a discrete signal. I have used the formula according to Barnes. I am ...
- 31
2
votes
2
answers
1k
views
Wigner-Ville Distribution (WVD) vs STFT for Spectral Analysis
What are the Pros and Cons of using Wigner-Ville Distribution for spectral analysis of a signal vs taking the STFT. When is it appropriate to use one over the other and is WVD used in real-time ...
- 500
4
votes
1
answer
465
views
Unwanted periodicity in data
my signal consists of data points that represent the (vibration signal) energy measured during process cycles of a machine. Due to the hydraulic power units emptying and filling again, some ...
- 43
1
vote
3
answers
549
views
Increasing STFT resolution by repeating the window? Ways to improve STFT resolution?
In theory of FT(Fourier transform) and STFT(Short Time Fourier Transform) it is said that "A narrower window gives good ...
- 135
3
votes
3
answers
609
views
Effect of overlapping percentage on STFT output
I know STFT is generally applied to non-stationary signals but I tried to apply it to a stationary signal to get a working knowledge.
I created a stationary signal composed of three frequencies as ...
- 33
2
votes
2
answers
716
views
The uncertainty principle - Why does it imply that we can't localise
The uncertainty principle states that if you have a signal which is very concentrated in time, then its Fourier transform will be rather outspread and vice versa. However, I don't really understand ...
- 129
3
votes
2
answers
272
views
Inverse of wavelet transform modulus gives poor results
I just want to understand, why is the result of my wavelet(?) transform so bad.
For $0\le i< k$, where I set $k$ to $10$, I split the signal in blocks of length $s_i:=2^{i+2}$, overlapping by $s/2$...
- 151
2
votes
1
answer
281
views
Conditions for analytical signal reconstruction with the Hilbert Transform (HT)
I'm new to the Hilbert Transform, I was reading the paper: "SISAR Imaging - Radio Holography Signal Reconstruction Based on Receiver-Transmitter Motion", and the next sentence was written in the paper:...
- 182