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Questions tagged [phase]

phase is angular shift between periodic signals.

phase is angular shift between periodic signals

  • for example signal x1(t)=cos(t) is the same as x2(t)=sin(t+PI/2)
  • angle PI/2 is the phase (angular shift) between sin(t) and cos(t)
  • phase is also used as angular coordinate for polar representations of phasor commonly used in electrical engineering
  • phase distortions of signals are called jitter
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Plotting phase in python with matlibplot

I want to plot phase properly in a 2d image using matlibplot and in particular the cyclic colormaps. I however get a weird line that I want to get rid of. Can anyone help me, I think there might be something wrong in the code. This is my code and…
user392269
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Two phase locking

I have been doing a few exercises for an exam, they dont come with answers so just looking clarification, it asks to find the errors in the table and to explain each error which 2PL principles it violates. I have came up with T4 at Step 14 cannot…
user445714
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Get angle into range 0 - 2*pi - python

In my simulation i compute multiple values for a phase, for example phi = np.linspace(-N,N,1000) where N can be large. Is there an easy way to map the values to the intervall [0,2pi) ?
Heißenberg93
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How can I effectively calculate the phase angle of a complex number that is (essentially) equal to zero?

I'm writing a C++ program that takes the FFT of a real input signal containing double values and returns a vector X containing std::complex values. Once I have the vector of results I then attempt to calculate the magnitude and phase of the…
tjwrona1992
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How to add a phase shift to a sin wave in the frequency domain with fft?

I want to shift a sine wave in the frequency domain My idea is the following: Fourier-Transform Add a phase shift of pi in frequency domain Inverse-Fourier-Transform In code: t=np.arange(0, 6 , 0.001) values = A*np.sin(t) ft_values=…
Kolibril
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VHDL - Phase Accumulator with feedback

I am trying to create a phase accumulator using VHDL that has the following characteristics. Inputs: D (Input signal) RESET CE CLK Outputs: Q (output signal - feedback) Source code: library IEEE; use IEEE.STD_LOGIC_1164.ALL; use…
Paul James
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Unwrapping atan vs. atan2

I can extract the phase of a complex number in Matlab using the atan() or atan2() functions. atan() returns in interval limited to [-pi/2,pi/2], and atan2() returns in interval limited to [-pi,pi]. I want to see if I can unwrap the extracted phase…
Liz Salander
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Issues with np.unwrap() in python. Phaseshifting

I have to plot a set of data which is in a 2-pi periodic box and there are discontinuities because of the periodicity of the values, so I used the numpy function unwrap() for discontinuities in pi or 2*pi, but it doesn't solve my problem. Below is…
ffalk
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Gnuplot: Making pm3d palette repeat when out of range

The plan is to plot the phase of a 2D-complex function using pm3d map and a repeating color-palette in a continous way. To be more specific, the palette is only defined on [-pi, pi], while the phase itself might run out of this range. The…
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how to decompose an image into magnitude and phase and reconstruct it again using Matlab?

How can I decompose an image (e.g. Lena) into magnitude image and phase image and reconstruct it again from those two images using Matlab? Here is the code I have written in Matlab but I dont know why the reconstructed image is too dark or too…
MJay
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Frequency domain phase shift, amplitude, hope size and non-linearity

I am trying to implement a frequency domain phase shift but there are few points on which I am not sure. 1- I am able to get a perfect reconstruction from a sine or sweep signal using a hanning window with a hop size of 50%. Nevertheless, how…
papaya
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How do I swap the phase responses of two images?

I applied the FFT to each image. I extracted the angle or phase of both image 1 and 2. After, I would like to swap the phase responses between both images but keep the magnitude intact. The code I have so far…
vincet
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Chartjs: Is it possible to add phases in line chart?

Hello I want to create a dynamic chart that looks like this: phases in line chart Is it possible with ChartJs to create vertical lines at certain milestones? (If possible also give each phase another color) If not, what other libraries can handle…
Ken Vernaillen
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how to get the phase of the cosine function from FFT

from DFT relation for cosine function we have DFT( cos(2*pifin) )=.5*( delta(f-fi)+delta(f+fi) ) as we can see the phase of the DFT is zero. However, when I use FFT in matlab, fft coefficients are complex which means the phase of the DFT is not…
user51780
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OpenCV: How to do phase shift the Fourier Transform?

I would like to create Hilbert Transform by doing phase shift 90 degree of Fourier Transform. I'm using OpenCV dft and idft for Fourier Transform and Inverse Fourier Transform…
HongAnTC AnAn
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