Questions tagged [impulse-response]
The impulse response of a dynamic system is its output when presented with a brief input signal, called an impulse.
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Calculation of response of continuous-time LTI system [closed]
Consider an LTI system defined by the following impulse response $S_{1}$
$$ h \left( t \right) = u \left(t - 6 \right) - u \left( t \right) \tag{1} \label{1} $$
Assuming $x \left( t \right) = 5 \left[ ...
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Characteristics of linear systems in the time and frequency domain
Why is the output signal obtained through frequency response different from the other two.
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Understand basic Impulse Response from Impulse, can you help me visualizing it?
I was looking at this graph from The Scientist and Engineer's Guide to Digital Signal Processing, copyright ©1997-1998 by Steven W. Smith:
where basically it shows how differnt representations can ...
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Analysis of impulse response in downsampling problem
Hey everyone, I'm stuck on this problem and I've got an exam in a few days. I think the filter H is used here so as to avoid aliasing artifacts, and afterwards went on to the second question.
I've got ...
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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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Algorithm to "serialize" impulse responses
New user to dsp.stackexchange here. I'd like to know what's a quick and effective way to take 2 impulse responses and create one that's equivalent to both of these "in series" for audio ...
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On FFT, interpolating signal vs extending signal in time
When we interpolate, then FFT the output will have more bins.
When we extend the signal in time, Then FFT output will have more bins too but:
Interpolation increases max bin frequency but time ...
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Impulse response aquired by ifft seems to require circshift
On the system below:
I have found W by inputing 20-1000 frequency and found amplitude and phase for each frequency. I've tested for minimum phase and none min S. But the answer is not logical for me. ...
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How do I obtain narrowband reverberation times in the bass range to detect room modes?
I calculate my impulse response according to this principle. Calculating the inverse filter for the (exponential) sine sweep Method. With the obtained impulse response I calculate my reverberation ...
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Equipment to test my theory on time varying systems
How can I make a linearly time varying system to test my theory?
Can I ask for a PID microcontroller available from my university such that $K$ is gradually increased from 0 to $c$
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How to get an impulse response of a MIMO system?
So I have data vectors from a MIMO system and I wish to see the impulse response
Any idea how I can proceed with this?
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Sine as input to an LTI system
Everywhere in theory (books , online) there is this statement "For sinusoidal inputs, any LTI has a sinusoidal output with the gain of $|H(s)|$, the same frequency, and a phase shift equal to $\...
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How to obtain an impulse response from an exponential sine sweep (23kHz/50kHz)
I am currently working on my master thesis and have so far generated a broadband ESS to obtain frequency response and impulse response.
To generate the ESS as an excitation signal I use the following ...
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How can I find the impulse responce of this ODE?
$$ \frac{𝑑^2𝑦(𝑡)}{𝑑𝑡^2} + 2\frac{𝑑𝑦(𝑡)}{𝑑𝑡}+ 1 = 2𝑥̈(𝑡)$$
a. Write Matlab source code evaluate the impulse response of the system.
b. Write Matlab source code to evaluate and plot ...
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Why does convolution give the output of a passing a signal through a filter?
I have a rudimentary understanding of Convolution, the Convolution Theorem and why the output z(t) of an LTI system can be found using the convolution of input signal x(t) and the impulse response h(t)...
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Modeling an Acoustic Reflection from a Wall - a Paradox?
I am trying to simulate the reflection of a sound ray, that goes from a sound source, bounces off a wall, and is received by a microphone.
The wall has a an absorption coefficient, and a specular ...
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upsample impulse response
I have a system and I know its impulse response $h$, this impulse response was recorded at $f_s = 48000 \texttt{Hz}$, now I can use Matlab to get the system output to an arbitrary signal ($x$) by ...
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Exponential/Logarithmic Sine Sweep - Inverse Filter Amplitude Correction
I am implementing the exponential/logarithmic sine sweep approach to impulse response measurement (as presented by Farina - http://pcfarina.eng.unipr.it/Public/Papers/134-AES00.PDF).
My query is ...
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How can Haar basis be written as the impulse response of an LTI system?
Haar wavelets are defined as:
$$\phi_{0,0}(t) = \begin{cases}
1, & \text{ for } 0<t< 1/2\\
-1, & \text{ for } 1/2<t<1 \\
0, & \text{ ...
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Getting different results when fourier transforming in python vs mathematica?
I am interested in troubleshooting why I get a very different answer when doing fourier transforms of my data in Mathematica vs Python. The version in Mathematica is well behaved, yet all versions of ...
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Controllability matrix is full rank identity matrix
What does it mean, when my system has controllability matrix that is full rank and identity matrix? Having full rank means that the system is controllable, but does the Identity feature of my ...
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Proof for LTI Systems [duplicate]
Suppose we have a system $S$.If I know the impulse response $h(t)$ I can predict the output for any input $x(t)$ if a system is linear and time invariant.However how do we prove that statement?
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Impulse response of linear time-varying system
I am confused about linear time-varying system. For a time varying system, the output is given by
\begin{align}
y(t)=\int x(\tau) h_{\tau}(t) d\tau,
\end{align}
where $ h_{\tau}(t)$ is the output of ...
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Construction of Room Impulse Response - Short-Time-Fourier-Transform and Inverse-STFT - Matlab and NWaves (C#) Implementation
Background:
I am working on a Unity Project (C#) and implementing a Room Impulse Response synthesis.
I do ray tracing to create energy histogram for different bands.
With these histograms it is ...
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LLTV Systems breakdown(2)
In this question I proved that for a linear linearly time varying system $S$ such that if $t_{2} = t_{1}+t_{0}$ then $h(t,t_{2}) = h(t,t_{1})+h(t,t_{0})\rightarrow$ $h(t,t_{0}) = g(t_{0})h(t) $ where $...
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Impulse response of a discrete time cascading system
My lecturer has decided that in order to pass our signal analysis class, we have to give a presentation on the blackboard in front of the entire class, so its kinda critical that i get this right. (...
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LLTV Systems linearity breakdown
Suppose we have a linear linearly time varying system $S$ such that the output depends on the input + the time at which the system becomes excited so $S(t,t_{0}) \rightarrow g(t_{0})S(t)$ and it is ...
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How to find the first and list point of an impulse in a RIR?
I'm looking for a simple algorithm where given a RIR sample file I can find the beginning of the impulse and the last point of the tail.
If possible, would love to implement it in python.
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Linear phase with a non-integer delay?
Let's say you are given a frequency domain specification for a filter design.
As a simple example, let's use an ideal (brickwall) LPF. Now the impulse response of an ideal LPF is a $\operatorname{sinc}...
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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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Get the inverse transfer function from the measured response
What is a numerically stable way to obtain the inverse transfer function from a measured response?
I have a system that shows a low-pass behavior. I would like to increase the bandwidth by some form ...
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Get the room impulse response by using inverse filter of sin sweep signal
I want to simulate the process of obtaining the impulse response of a room.
What I did:
Generate a room impulse response sequence by using the python module: ...
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Linear Linearly Time Varying Systems properties?
Yesterday I asked a question about LTV Systems and how the impulse response h(t,t0) is found.
I was thinking about it and realized there is a subsclass of LTV systems which I call Linear Linearly Time ...
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Integral of product of two shifted Dirac impulses
In this question the multiplication of two impulse functions is discussed
However, what if I have two shifted impulses say:
$z(t) = \delta(t-\tau)\cdot \delta(t-\beta)$
Now if I want to integrate $z(t)...
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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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A response of an unstable system
I'm dealing with the following question :
The system realizes an accumulator, therefore its impulse response (h[n]) is just the unit step function multiplied by some factor . In the next subsections ...
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Causality of an estimated filter
Assume $\tilde{h}(f)$ is a filter estimated by an algorithm for (room) impulse response estimation working in the frequency domain.
Is there a way to assert if such filter is causal?
Specifically, ...
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LTI system: can I infer the system is causal based only on the transfer function without the ROC?
Suppose we have an linear time-invariant (LTI) system which acts on discrete signals. Suppose someone tells us the transfer function is: $$H(z) = \frac{1}{z-2},$$ but doesn't specify the ROC. Now the ...
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Finding start point of a curve
I'm currently working on a project where I have to measure the latency of a given system.
Below you can see a exemplary image which shows the input pulse (green) and the response (blue).
In order to ...
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A Python code for blind estimation of RT60 from recorded audio
I have an audio recorded, recorded by a 2 mics array. I want to a Python code that get the audio as input and estimate the RT60 reverberation time. I do have a function that estimates RT60 from a ...
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How can I obtain the impulse response using a dual channel FFT?
I want to obtain the impulse response of a space to calculate reverberation time using the Schroeder method. This space is characterized by the short reverberation time within 0.5 seconds due to the ...
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How can I compute the coefficientsof the impuse response given a signal? [closed]
How can I compute the coefficients of the transfer function with the following difference equation:
$$y[n]=x[n]+y[n-1]-0.5y[n-2]$$
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How to find impulse response of the input signal in Python?
I had to read input .wav audio file first, then add Gaussian white noise to the input audio signal and I've finished that part. Now I have to add a channel model whose impulse response is:
...
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Find the impulse response of a causal 52 day moving average system to be used in stock market [closed]
Moving average system……………………….
How to solve this one?
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Find impulse response and frequency response
Given
$$x(n)=\left(\frac{1}{3}\right)^{n}u(n)-\frac{1}{5}\left(\frac{1}{3}\right)^{n-1}u(n-1)$$ the input to a LTI system, and output
$$y(n)=\left(\frac{1}{4}\right)^{n}u(n)$$
Find impulse and ...
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Relationship between impulse response output and input in discrete systems and signals
Does the equality $H(n_{f}) = \frac{Y(n_{f})}{X(n_{f})}$ hold for discrete signals in the discrete Fourier domain?
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Impulse response amplitude : Sine sweep method
I'm trying to implement Farina's method in python to measure impulse response with an exponential sine sweep.
I convolved the output of the system with the inverse filter of the exponential sweep.
...
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Identification of properties of a given FIR filter
I have a FIR filter which is described via following transfer function
$$H(z) = h(0) + h(1)\cdot z^{-1} + h(1)\cdot z^{-2} + \ldots + h(23)\cdot z^{-23},$$
where the coefficients have below given ...
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Solving for the Kernel of a system using impulse balancing with diracs delta's derivative
I wanted to practice Impulse balancing and tried using it to solve this IAR system in one go as opposed to using its LTI attributes. The exercise wants me to find the impulse response of the system:
$$...
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How to find the impulse response of a room using a sine sweep signal?
Using the Exponential Sine Sweep (ESS) method and my test equipment, I am trying to find the impulse response (IR) of a room which contains a great deal of sound absorbing material. Ultimately I want ...
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