Questions tagged [phase]
A quantity representing the fraction of cycle of a periodic signal, usually represented as an angle.
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how to log phase of NWC Australia 19.8KHz in a file in python
First I am very new in this field,and i am doing a college project and i stuck at determining phase of msk signal which is transmitted from a radio stations called NWC Australia 19.8Khz , so let me ...
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Modelling phase noise for self-heterodyne method
I am trying to model the phase noise $\phi(t)$ of laser used in self-heterodyne method using python code. The noise is time-dependent. The noise follows the condition that
$$\langle(\phi(t)-\phi(t-\...
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Phase Spectrum of Signals
I did fft of a fish's trajectory, because it looks periodic and I tried to find the frequency. However, I can't understand what does the phase spectrum below represent. Does this lower left to upper ...
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phase unwrapping relative to a reference
I have samples of wrapped $(-\pi,\pi)$ phase from a bandlimited signal
$A(t)\cos(\pi\omega t + \phi(t)+\theta_0 )$
Frequency is constrained by very regular physics and I know a preliminary guess $\hat{...
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Phase compensation using IIR allpass filters
As an exercise with IIR allpass filters, I am trying to compensate the phase of a lowpass Linkwitz-Riley filter using the Matlab integrated function iirgrpdelay.
The code I am using is the following:
<...
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Filtering after a phase domain ADC
While researching receiver architectures for the demodulating constant envelope signals like a GFSK, I stumbled over the concept of phase domain ADCs, where after
$$\boxed{\text{LNA}}{\longrightarrow}\...
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Integrating CWT around nominal frequency with amplitude and phase
I have a real signal f sampled at 96Hz composed of clusters of harmonics scattered tigthly around evenly central frequencies close to 1Hz and 2Hz (multiples of 0.966Hz) that I'll call features. These ...
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Finding phase of a received signal using spectrogram function
I am trying to find the phase of my dataset between a range of frequencies. I can't post my code or data but generally speaking, the frequencies range from 10 to 100kHz and I need the phase between 20 ...
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Real world use case for a battery with phase?
Referencing the following exercise by Dan: $9\rm V$ Battery with $45^\circ$ phase, I'm curious on what this would be used for in real world applications?
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Computing Phase detector in PLL
I have been trying to implement PLL in a STM32 microcontroller. Starting with the first step, I want to implement a phase detector. I tried to first simulate in Python so that I can later use in STM32....
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Computing phase difference between two sinusoidal signals
Based on this post here, I tried to calculate the phase difference between sine waves. Here is my code.
...
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Correlated phase noise
I am trying to find a mathematical model to understand the correlated phase noise.
Here, I see the reference phase noise is almost the same after up-conversion and then down-conversion. How does ...
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FIR filters: is it possible to manipulate phase without change in magnitude response
Here's response of FIR design:
which shows SPL 0dB and here's a wave file exported from ( DRC ) FIR design software: FIR48kHz.wav.
Audio software (internally uses FFTW routines) where this filter is ...
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Scenarios where Phase Response is (non-)problematic
In order to get a better feel for phase response and how it applies across the field of dsp, I'm looking for example scenarios where a filter's phase response is a concern and where it is not.
Take ...
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How to calculate phase estimation error
I am working on speech enhancement and I want to compare the phase and magnitude between two signals. I compute the STFT for both, and comparing the magnitudes is easy via mean-squared error or some ...
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Phase of signal can affect the data rate?
Does the change of phase of the signal affect the data rate?
Actually, I consider the RIS(Reconfigurable Intelligent Surfaces) between the transceiver and receiver. I wonder if adjusting the phase ...
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What could be the cause of oscillating differential phase between a 2 channel audio signal
Test Setup
I have two i2s microphones (INMP441) on a common clock. They are designated as the left and right channels with a sampling rate of 22050Hz. The generated signals are stored as WAV files and ...
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visualizing frequency and phase of a system's response to an impulse
Given a .wav file that is a LTI system's response to an impulse, what would you recommend as the simplest way to plot the frequency and phase output of the system? I'm already working in Python, so ...
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MSK without I/Q data
I just started a while ago with DSP and slowly staring to understand the concept of I/Q and what it means. I successfully could decode some bfsk, bpsk and wanted to move to msk which as not easy to ...
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How to remove Phase Offset from PSK signal?
Suppose you have captured IQ data from a PSK modulated signal with intermittent blanks between signal transmission as shown in the figure below.
I want to be able to automate and run an algorithm on ...
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Depth estimation using phase shifted sine waves
For 3 phase shifted sine waves using the projected pattern: I = sin(x + δi) where δ ∈ [-2pi/3, 0, +2pi/3] which is then projected onto a scene. The resulting image is captured with a camera. I am ...
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Why is phase lost in x-ray crystallography?
everywhere says that phase is los but WHY?
it is that when we measure x rays we cannot measure phase?
is it that phase is lost because of such high scattering?
what is the REASON for the phase lose in ...
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Deducing phase from frequency response $1-z^{-1} $
In Boaz Porat's book about signal proccessing, at part 8 he mentions the example:
$$ H\left(z\right)=1-z^{-1}\Rightarrow H^{f}\left(\theta\right)=1-e^{-j\theta}=\left(e^{\frac{j\theta}{2}}-e^{-\frac{j\...
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Phase Difference Calculation in Frequency Domain
I am currently working on an application in which I have a Linear acoustic array, the audio of which is analyzed using FFT. Now I also want to perform phase difference calculation and have also learnt ...
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Demonstrating zero phase of vertically symmetrical signals
I'd like to get a zero phase for vertically symmetrical signal (as it done here, FIGURE 10-7).
For this purpose, I tried to test it on gaussian signal in Python:
...
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Is there a ''standard'' or commonly accepted reference for the phase of the most usual signals?
I am working with some very common, simple signals, such as square, triangle and sawtooth.
In my case the phase of such signals is important, so I want to be consistent throughout my work. For example,...
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How to get correct phase values of the signal using Recursive Discrete Fourier Transform
Question
I'm trying to understand the relation of the result of the recursive DFT to the original signal. I have a signal with a sampling frequency of 4000 Hz and the recursive phasor estimation ...
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Doppler radar: phase shift sign convention
In my reading about Doppler radar principles, both of the sources I've been using have made a peculiar choice of sign convention: the phase shift of the received pulse relative to the transmitted ...
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Phase vocoder has crackling artifact
I built a phase vocoder in JavaScript based on this paper. It works great, except for a crackling artifact that is present in the rebuilt signal.
I recorded this clip if you want to hear what it ...
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Best parameter to estimate image reconstruction quality?
Context: I am a PhD student in physics and right now I am studying phase retrieval with low illumination
With two different parameters I obtain these two images:
With hight illumination (less noise) ...
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How to sum amplitudes only without distorting the signal?
I do audio signal processing using Python (scipy, numpy etc.) I'm trying to "mix" 2 audio signals in a way that reduces phase canceling as much as possible. So I do an FFT of the 2 signals, ...
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Deriving the IF phase equation of FMCW
My understanding of the FMCW was limited to one chirp and was mostly focused on frequency analysis. (Mostly built upon this answer)
I wanted to expand my understanding to multiple chirps and was ...
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Sampling Time Offset estimation for OFDM signal
I have a signal constituted by known OFDM symbols, and my goal is precisely estimate the Sampling Time Offset (STO). However, while the STO in the context of a single-carrier modulation is pretty ...
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numerical time differentiation in GNURadio
I'm hoping to put together a cheap modulation monitor for wideband FM radio using an rtl sdr usb, on the FCC website, it's listed that the modulation percentage for an FM station is the actual ...
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Why does an FFT-based filter change phase?
I am very new to DSP, and I'm just trying to figure stuff out here. I saw a video which stated that a filter implemented using an FFT would alter the phase of different frequencies differently. The ...
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Finding the maximum frequency deviation and phase deviation
I'm trying to solve a problem regarding communication and I'm stuck. The questions asked me to find the maximum frequency deviation are usually written in cos or sin wave. But this question isn't, so ...
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Adding $n\pi$ to the phase when estimating the phase velocity of a sound wave through a material
Setup
I'm estimating the phase velocity in a wooden table by using an actuator and 3 sensors. The actuator sends out a chirp and on the table there are 3 accelerometers with distance $d$ between them. ...
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Spectral leakage with phase error? Complex convolution?
As we know, phase is very important for a signal.But I don't know much about the cause of phase errors.
Spectral leakage is equivalent to convolution of the spectrum of the original signal and the ...
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Reason for "buzzing" artifact over processed audio after IFFT
I made a program that can change pitch of a recorded audio clip while maintaining its duration. Basically, it takes the FFT of windowed segments of a recorded signal, processes them using phases to ...
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Behavior at DC and Nyquist of an ideal phase shifter
In Matt L's answer he states that an ideal phase shifter with a phase shift $\theta$ has a frequency response
$$
H(\omega)=
\begin{cases}
e^{-j\theta},&\omega>0 \\
e^{j\theta},&\omega<0
\...
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Synchronization of two noisy sinusoidals signals
I have two noisy sinusoidal signals and I am currently investigating solutions to synchronize them using python. Here is an example I made to illustrate my goal, supposing that I generate these two ...
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IIR Allpass Filter Phase Response Plotting in Excel
Using formula on Audio EQ Cookbook I implemented biquad IIR filters in Excel.
As in my previous question Phase Response Function / Plotting in Excel (IIR Filter), Hilmar helped a lot with the phase ...
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Phase Response Function / Plotting in Excel (IIR Filter)
Using formula from Audio EQ Cookbook I implemented biquad IIR filters in Excel.
I can now plot every transfer function and total of 8 band EQ with shelvings and peakings.
My problem is, I can not ...
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How to correctly get the amplitude and phase of the signal after applying the fast fourier transform to it
I am new at signal processing and was trying to understand the relation of the result of the FFT to the original signal.
I generated a signal with a sampling rate of 100 Hz within 1 second ($N=100$), ...
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Wrapped phase and phase unwrapping in vital sign detection
I am quite new to the world of radar signal processing and there is this issue that I can't figure out for the life of me.
In Remote Monitoring of Human Vital Signs Using mm-Wave FMCW Radar (Section ...
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Phase Unwrapping Issue of IQ data sample in Radar Signal Processing
I am doing radar sensor signal processing.
The radar sensor gives iq data corresponding to the range (sweeps).
I want to detect micro motion so that phase analysis is used.
Sweep is the distance ...
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$S/N_0$ of a PM Modulated tone
I have been looking into a Satellite tone ranging system.
Phase error Performance criteria has been given as a function of $S/N_0=40 dB.Hz$ of the Major tone.
The major tone is 100 kHz away from the ...
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Why do I get a phase of the FFT of a cosine function when the phase is zero?
I'm trying to find the phase of a cosine function with the FFT but I don't understand the results from the plots. I did two separate examples for two phases $\phi$: $\phi_1 = 0$ and $\phi_2 = \pi/3$. ...
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Is the magnitude of the phase shift independent of the volume of the sound?
Sound waves can cause vibration of the particles/objects that are scattering/reflecting/emitting the light. Since vibration is spatial displacement, it causes a phase shift by affecting the value of &...
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How to explain the meaning of the intersection in a Fourier series representation of periodic signals?
I saw a piece of code on github which transforms the planetary movement into the Fourier wave function.
These circles are given by the $x$ and $y$ ordinates: $x=\cos (\omega t)$, $y=\sin (\omega t)$, ...
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