Questions tagged [time-domain]
The time-domain tag has no usage guidance.
134
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Filter a 1D time series taking advantage of accuracy values for every data point
I have an assignment on a time series that contains the x positions of a point in space. This series comes with another one of the same length, where every element goes from 0.0 to 1.0 and represents ...
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Filtering in time domain vs filtering in frequency domain
The signal is an impulse repsonse. I am filtering the signal using a windowed sinc filter in both frequency and time domain. I am interested in knowing the differences between the two methods and ...
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135
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Applying Lowpass filter on a signal in time domain gives ringing artifacts - how to get rid of them
EDITED AND UPDATED:
My signal is an impulse response. In the following figure:
The frequency spectrum of the impulse response (original signal) is shown by blue line.
The original signal is ...
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Improving the Time Domain Normalization of Acoustic Sound Data
I have tried to evaluate the analog microphone (IMP23ABSU) built into the STEVAL-STWINKT1B with the FP-SNS-DATALOG1 (HS-Datalogger). The values were exported as "raw values" (this is an ...
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Sampled data plot doesnt make sense
I've measured an accoustic signal for approx. 90 seconds with a sample frequency of 192 kHz (Note: the used device can sample data with maximaly 192 kHz, therefore i am not 100% certain, what sample ...
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Decreasing gibbs phenomenon with window functions multiplied in time domain
I know about using fitering(e.g. window filters that used in frequency domain), wavelets for decreasing or even full eliminating gibbs effect but don't really understand how we can use window ...
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70
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Time-varying shot noise generation
I'd like to model the behavior of photodiodes, the input is like data bits (0 & 1) where each bit is represented maybe with 100 samples / bit and the bit rate is $B$ bits/sec with period $T_{bit}=\...
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control system : time domain analysis
This is the question. According to this, when we solve for transfer function we will get $20/s^2+5s+24$. but this is not the correct format as numerator should be equal to the last term, i.e., 24, in ...
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Relationship between the derivative of a time-stretched signal and its original derivative
Suppose we have a time bounded original signal f(t) where f is nicely behaved, for simplicity we can restrict it to a polynomial. The crux of the problem is that its analytical form is unknown, we ...
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977
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Why is the convolution of two sine waves a sinc function?
Problem/Question
After taking the convolution of two discrete sine waves of the same frequency and length the result appears to be a sinc function but I was expecting to get a sine wave since this ...
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Scaling for windowed differentiator FIR filters
I recently took a dive into DSP and I was wondering what the appropriate scaling factor for a wide-band differentiator is.
Let's derive the impulse response of such a differentiator.
$$\begin{aligned}
...
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How to plot a sawtooth chirp waveform using an array of frequency and time for an FMCW radar?
Before switching to use sawtooth I was using sine wave but in sine wave high frequency content was not clearly visible, But I don't have any experience with using sawtooth waveforms. I am going to ...
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Is it possible to predict the peak value of a time-domain signal from its frequency-domain spectrum?
As the question states, is it possible to predict the peak value of a time-domain signal given its frequency-domain spectrum?
Since the time-domain signal is just the sum of the individual sinusoids ...
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42
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Normalize the output signal that may be as similar as possible the input
I'm having a problem to normalize my output signal (extracted EEG signal) after applying Independent Component Analysis (ICA) that may be as similar as the original source (EEG signal). I need do this ...
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Need to make audio human listenable
I wrote some golang code which implements 3Blue1Brown's Hilbert's Curve: Is infinite math useful? ... give the code an image and it returns back its audio equivalent ( inverse Fourier Transform ) ......
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Help with real-time TD-PSOLA - sounds very very bad
So I have a pretty robust and fast pitch tracker I've been working on based on this thesis. I want to use it for real-time pitch shifting. However, one of the simplest algorithms for formant-...
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Short time energy or root mean square?
What is the difference between Short time energy(STE) or root mean square(RMS), Librosa library offers a function to calculate RMS but doesn't offer one to calculate STE, which gives the impression ...
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time-domain response to continous linear chirp
I am investigating the time-domain response of electromagnetic waves. The input signals are a chirp with linear frequency sweep 2.5 Hz->4.5 Hz -> 2.5 Hz and another signal which is abruptly ...
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IFFT confusion, sampling frequency
I made a previous post about what I am trying to do
Previous Post
I have band-limited data in the frequency domain from a VNA and I am trying to convert it into the time domain. VNA data saved in .s2p ...
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114
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Impulse response of an LTI system
I want to find the impulse response of the linear time invariant system given by
$y''(t)+4y'(t)+3y(t)=x'(t)+2x(t)$
using time domain analysis.
As solved in the textbook "Continuous and Discrete ...
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Time domain frequency "loudness" isolation
There is a very useful tool in my DAW which allows me to isolate groups of "loudness" within the frequency domain. Basically, any bin greater than some min, less than some max. It makes it ...
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461
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Constellation Mapping In OFDM
If i am not mistaken, the two following hold :
a. In OFDM Conceptualization, the constellation mapping at Tx (or de-mapping at Rx) is done in Frequency domain
b. However the basic theory (Including ...
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122
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What is the name for the technique of comparing a time domain signal to an expected signal with a sliding window?
I was trying to think about how to do time-domain analysis of a real-valued signal to determine if it contains a particular carrier. I can obviously just compute an FFT, but that transforms a window ...
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195
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How can I check similarity of two different sinusoidal waveform model?
I am trying to establish a similarity index for two different signals. These signals are quite different in amplitude and signal length. Their waveform is sinusoidal, and frequencies are at a close ...
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Resampling a signal with variable frequency [duplicate]
I haven't touched my signal processing courses for a long time and I forget how to work with these kinds of signals.
I have a signal that comes from a sensor that has 3 time periods.
The time vector ...
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42
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If I have this discrete time sinusoid composed of a sine and a cosine, how do I find its period?
$$ x \left[ n \right] = 3 \sin \left( 4 \pi n \right) + 2 \cos \left(0.36 \pi n \right), ~~~ 0 \leq n \leq 100 $$
The fact that my signal is composed of both sine and cosine makes it tricky for me.
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Algorithm to detect down-up-down pattern in time series
I'm trying to write an online algorithm in Python to detect this below Down-Up-Down pattern in time-series.
It's not hard to do roughly if I calculate 3 contiguous non-overlapping moving averages, and ...
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68
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Analytical derivation of convolution and multiplication implement of time-domain signal
I have a system model as shown in figure 1. I want to change the model to a new schematic as in figure 2. How to analytically derive the filter $H_2$ if all parameters are known?
I guess that we will ...
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201
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FIR filter phase response at fs/2
I am currently building a FIR filter based on frequency sweeping data (0 Hz to Fs/2), i.e., transfer curve in frequency with the sampling rate of Fs.
The phase response is shown in the following ...
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443
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Multiplication in frequency domain for a signal containing a whole frequency spectrum
Imagine we have two signals in the frequncy domain X(f) and H(f), for one of the signal H(f) I have the complex pair and the frequncy at which that complex pair exists. The second could be any random ...
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118
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Low pass filter behavior in frequency domain
I have a relatively simple task, which is to implement a low pass filter for a sum of exponentially dampen complex sinusoids in random Gaussian noise.
To showcase my problem I have generated data ...
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545
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How to estimate the delay in time domain when knowing the phase shift in frequency domain
I am strugling with how to compute the exact value of delay in time-doamin when knowing phase shift in frequency domain.
I have a analog circuit, I sweeped about 30 single tones frequency ranging from ...
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752
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Getting envelope of noisy signal
I am analyzing some interferometry data and have a time signal that looks like this:
Our temporal resolution is unfortunately not enough to resolve the fringes.
I need to get the upper envelope of ...
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Impulse Response Formula
How can you determine the impulse response if you know the output of the system?
You should change the input signal with the dirac function with the argument equal to $t$ or $t-\tau$?
I have this ...
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274
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Frequency filtering in the frequency domain vs. time domain
As a DSP newbie, I've stumbled into doing band pass filtering (of pre-recorded IQ data) in the frequency domain - which allows brick wall filtering (I'm just setting the IQ values of each consecutive ...
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How to sample a signal in time based on a set of relaxation times?
How fine should you sample in time (and what should the range be) when calculating a spectrum based on some relaxation times ("modes" in physics, not sure about signal processing). I have ...
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How to interpret ADEV plot?
I want to understand how to interpret ADEV plots. I was of the understanding that if we see a peak at 1sec of TDEV plot there is a 1Hz noise in Time Interval Error(TIE) Capture.
To understand the ...
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Converting signal to frequency domain then back to time domain - noise issue
I am trying to convert a signal into frequency domain using fft then construct a time domain signal (with any length) from the frequency response. With my matlab code, it works fine when there is no ...
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Should I use IQ data or power data to compare 2 signals through `similaritymeasures.dtw`?
I choose similaritymeasures.dtw to compare experiment signal exp_sig and reference signal ref_sig.
Both signals are I,Q data ...
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Time Shifting, Reversal and Delay
For a signal, $s(t)$ undergoing multiple transformations of time scaling, reversal and delay, how should I approach the problem of finding the resultant output signal?
$$s\left(\pm \frac{t-t_0}{T}\...
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958
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Measuring rise and fall times, of square wave
I have recorded a square wave with scope(bit, controlling some unit).
I want to measure rise/fall time, the time while the bit is on and off using python. I thought of using the 'derrivetive' ...
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420
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Misunderstanding of Nyquist sampling theorem and minimum sampling rate
I sample my time-domain (TD) signal using a distance between time-samples of $\delta = (t_{max} - t_{min}) / N_t$, where $N_t$ is the number of samples taken. The sampling rate is $1 / \delta$.
I have ...
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How to calculate signal after passing through the filter?
I have the amplitude response of the LPF (here it is generated in Python):
...
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Defining a discrete sequence along an arbitrary time axis
I need to compute the output of the system y[n] = x[−n]. x[n] is of length 1 : 26866, and the y[n] output axis has the same length and goes from -12850 : 13975.
variables:
x[n] = x1,
output axis y[n] ...
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Beginner Q: Methodology of processing 5 kHz accelerometer signal for event detection
I'm very new to the world of signal processing and looking for some guidance.
I have 5 kHz accelerometer data from a car and looking to process this to remove some of the high frequency noise and also ...
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Why aren't the integrator and the differentiator inverse systems?
I have a statement that leads to a paradox, but I'm incapable of finding the part where I'm wrong.
The integrator system
$$x(t) \mapsto y(t)=\int_{-\infty}^{t}{x(\tau) \, {\rm d} \tau}$$
is a linear ...
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Why is modern control theory in the time domain instead of the S-domain?
I am not sure if I am missing something, but from what I read I understand that modern control systems work in the time domain rather than the frequency frequency or S-domain.
Wikipedia article ...
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I tried two approaches and gained the different conclusions of judging the stability of the transfer function of the system
We want to judge whether the system is stable or not.
Given the below transfer function.
$$ H\left( z \right) =\frac{\left( 1+2 z^{-1} \right) }{\left( 2+z^{-1} \right) } $$
$$ H\left( z \right) ...
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Train of impulses in frequency domain
Why compressing a train of impulses in time domain produce a wide-spaced train of impulses in frequency domain and vice versa? i want to know the intuition behind that.
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Where to start with DSP?
I have a DSP exam coming up this summer and I got an abysmal mark on an assignment earlier this year. Obviously, the lecture slides are not enough for me to understand DSP, so I am wondering where can ...
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