Questions tagged [time-domain]
The time-domain tag has no usage guidance.
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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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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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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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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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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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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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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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104
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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?
$$s\left(\pm \frac{t-t_0}{T}\...
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168
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Measuring rise and fall times, of square wave
I have recorded a square wave with scope(bit, controlling some unit).
I want to measure rise/fall time, the time while the bit is on and off using python. I thought of using the 'derrivetive' ...
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Misunderstanding of Nyquist sampling theorem and minimum sampling rate
I sample my time-domain (TD) signal using a distance between time-samples of $\delta = (t_{max} - t_{min}) / N_t$, where $N_t$ is the number of samples taken. The sampling rate is $1 / \delta$.
I have ...
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How to calculate signal after passing through the filter?
I have the amplitude response of the LPF (here it is generated in Python):
...
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Defining a discrete sequence along an arbitrary time axis
I need to compute the output of the system y[n] = x[−n]. x[n] is of length 1 : 26866, and the y[n] output axis has the same length and goes from -12850 : 13975.
variables:
x[n] = x1,
output axis y[n] ...
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Beginner Q: Methodology of processing 5 kHz accelerometer signal for event detection
I'm very new to the world of signal processing and looking for some guidance.
I have 5 kHz accelerometer data from a car and looking to process this to remove some of the high frequency noise and also ...
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Why aren't the integrator and the differentiator inverse systems?
I have a statement that leads to a paradox, but I'm incapable of finding the part where I'm wrong.
The integrator system
$$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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How to reconstruct the signal using overlapping frames in MATLAB
I understand that we can use the buffer function in matlab to split a long signal into overlapping frames. But is there any functions that we can use to put the ...
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The plot of instantaneous power of the Dirac function
I am very confused. I have tried researching this question for the last two weeks and I cannot get a conclusive answer.
I was wondering how would I go about plotting the instantaneous power in the ...
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127
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How to do sliding window multiplication in frequency domain
I want to perform the following computations with the impulse response of length L of a LTI system:
Multiply the impulse response with a window w(n) of length M << L.
Take the FFT of the result ...
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Why does Phase-locking value show spurious effects at the beginning & end of a signal?
I am trying to understand the behaviour of the phase-locking-value, as e.g. defined here, by some simple examples.
Basically, I am creating two signals with the same frequency & amplitude, where ...
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How to find duration of signal from spectral domain?
I have spectral domain and I have to find duration of this signal (in time domain). How I can find?
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280
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Is there a way to use decimation or linear interpolation to shrink or stretch an audio signal in the time domain?
I am able to shrink/stretch an audio signal using Python code for a phase vocoder, as well as the stretchAudio function from Matlab's Audio Toolbox. Although both methods do indeed alter the audio ...
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Is Kaiser-Bessel filter good for notch filtering with time-sensitive data?
I'm working with ECG signal processing and want to implement digital notch filter. Would Kaiser-Bessel filter be optimal for signals sensitive to time domain disruptions or should I use different ...
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Time domain representation of a modulated signal when symbol rate >> carrier frequency?
I need to understand the relationship between carrier vs. bits with PSK modulation, and what the signal in the time domain would look like if my symbol rate is far greater than my carrier frequency. ...
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I am looking for an analytic description of a continuous-time Butteworth High-pass filter in the time domain (=impulse response)
having derived the Butterworth Lowpass Time domain response, I am now struggling to find a similar function for a Butterworth Highpass filter. I understand you need to replace s by 1/s. But this leads ...
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Any guidance on converting Time Domain to Frequency Domain in Matlab
Below is the graph of my load cell readings at 3 samples per second. I have collected 500 such samples. I want to stabilize the readings and read that first approach is to convert time domain data to ...
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Meaning of the frequencies vector using fft
I'm so confused, and it would be nice if someone could clear my head, or at least direct me to suitable references.
Assume that I have two gaussian pulses with the same bandwidth in time, but for 2 ...
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Derive Time-Domain Biquad Coefficients from Z-Domain
I'm trying to derive the time-domain coefficients of a biquad filter based on its z-domain coefficients. The purpose is to import externally-generated EQ filters (in z-domain) into Max/MSP (in time-...
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Generating a time domain signal using the fundamental frequencies
I currently have the power spectrum (in dB) of a signal through which I obtained the fundamental frequencies and amplitudes. My question is: how to generate a time domain signal using these amplitudes ...
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Rectangular Pulse Train and Sinc Function
I wanted to ask that in frequency domain the rectangular pulse is a sinc function, so is this sinc function periodic or aperiodic?
Also if signals that are continuous in time domain then they are ...
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Third octave band zero-phase forwards-backwards Butterworth filter adds amplitude to complex signals?
Overall aim: to take a short signal (likely to be noisy with some tonal components) and filter it into third-octave bands (TOBs), apply frequency-dependent spectral adjustments, then recombine the ...
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Determining the right order of time-domain low pass filter for desired cutoff frequency
I've been stuck on a problem regarding complex demodulation of a signal for a while and wondered if anyone could help.
Suppose I have a signal $X(t)$ such that
\begin{align}
X(t) &= A(t)\cos(\...
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How to calculate DTFT of cosine function divided by n
I'm having a hard time to calculate the next function, and I don't really know Matlab good enough to calculate it there.
Help would be appreciated:
$$h[n]=\frac{A_1 \cos[\theta_1(n-N/2)]}{n-N/2}$$
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Time domain analysis vs frequency domain analysis? Applications wise? [closed]
When do we use time domain analysis and when do we use frequency domain analysis?
As far i studied i know that when we need to study individual sinusoidal components of a signal, we choose frequency ...
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Are there any recursive online max/min filters for time-series
Are there any online recursive filters that can approximate local, time-varying minimum and maximum values of a time series?
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A one-pole LPF (6 dB/oct) has a step response to $1/e$ amplitude of ${\tt time} = 1/(2 \pi f)$. What would the response time be of a 3 dB/oct filter?
I was instructed in another question here that if a one pole (6 dB/oct) low pass filter is fed a discontinuity (ie. going from 1 to 0) it will take ${\tt time} = \frac{1}{2\pi f}$ to reach $1/e$ ...
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Is a LTI system with dead-time equivalent with a LTI system with no dead-time but delayed input signal?
I wonder if the system parameters would remain the same after all.
According to the definitions, the gain is the change of the output induced by the change of the input if we assume that the gain is ...
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Questions about autocorrelation, correlation, and randomness
I'm learning about autocorrelation functions and trying to calculate some from a time series. Conceptually, what is the difference between the following two autocorrelation functions?
$$g_{1}(\tau)=\...
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Time domain to angular domain approach
I have a rotating shaft where I need to move from the time domain to the angular domain to look for vibration faults. I have the data from a tachometer.
From another post I found these steps:
The ...
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Time and Frequency Domain Relationship
Why do we say that a good time response means a bad frequency response?
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396
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Frequency and Order maps
I'm new to python and I'm using it to analyse accelerations from an accelerometer ie. vibration analysis. For that I need to plot 2 types of diagrams:
1) Frequency map; frequency and time on the axis ...
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Time Frequency bin
I am doing research in audio signal processing for DOA estimation. I came across the term Time-Frequency bin. I have gone through several articles but none of them specify a TF bin rather it specifies ...
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Butterworth filter transfer function in time domain
Preliminaries
I need to know the response of Butterworth filter in time domain of the following input (at least numerically):
$$
x(t) = \theta(t)(1-\exp\{-at\})\exp\{-bt\}, \quad a,b>0,\quad a\gg b
...
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