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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questions with no upvoted or accepted answers
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Multilateration of Sound in 3D Space
TL:DR - How can you find the 3D coordinates of a emitter than transmits an impulse signal?
STORY:
I'm working on something to improve my bird-watching. I've got a camera that can take pictures of ...
3
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0answers
192 views
Room Impulse Response Inverse Problem
This article here talks about a room impulse response generator which takes the source and destination coordinates, sound speed, sampling rate, room dimension and wall reflection coefficients as input ...
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88 views
Find a LTI system such that $\mathcal{T}\{\frac{\sin t}{t}\} = \frac{\sin 2t}{t}$
Let
$$x(t) = \frac{\sin t}{t} \qquad\text{and}\qquad y(t) = \frac{\sin 2t}{t}$$
Is it possible to find a LTI system such that $\mathcal{T}\{x(t)\} = y(t)$?
If not, what's the reason for ...
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75 views
Extract Impulse Response of a System From its Input/Output Waveform
I am a new engineer for signal processing field.
I want to extract the system impulse response from input and output of the system, i.e. so-called system identification, more specfically, for ...
2
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2answers
496 views
Calculating impulse response of system
Given is the illustrated circuit diagram of a linear, time-invariant, time-discrete system:
How do I show that the total system has the impulse response $h[n] = aδ[n] + bδ [n - 1] + cδ [n - 2]$ and ...
2
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0answers
128 views
Peak detection for signals that contain high frequencies
I have an question about peak detection. My purpose is creating a plot with an impulse response and the decay line at / above it.
What I see till now is that there are two options for finding peaks:
...
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0answers
8k views
Difference between natural response and forced response?
Reference
Second post on EdaBoard.com
Time response of a system is the time evolution of the variables. In
circuits, this would be the waveforms of voltage and current versus
time.
Natural response ...
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49 views
The impulse response of a LTI discrete system is $h[n]=\big(\frac{1}{3}\big)^n u[n]$. Find the response of this system to the input $x[n]= e^{jnπ/4}$
Hi I'm trying to solve the problem when studying for an upcoming test.
The given solution is
$1.2503 e^{jnπ/4 -0.2991}$, and is found by computing $H(Ω)$ and evaluating this at $Ω=π/4$.
when I try ...
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vote
1answer
26 views
Impulse invariance vs. DT representation of a CT system: Where is the inconsistency?
Suppose you have a continuous-time (CT) system $h_c(t)$, bandlimited to $B$. Your goal is to represent the system as a discrete-time (DT) system $h[n]$, sampled at $f_s \leq 2 B$. Clearly $h[n]$ won't ...
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1answer
109 views
Bode plot from from step response data
For quality control, I want to measure the frequency response of hardware I built. What I can easily generate on the hardware is a step response. Thus, I want to derive the magnitude and phase from ...
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1answer
61 views
Identifying impulse based on experimental data
I have conducted an experiment in which the impulse was exerted on sound bowl (it was hit by a hammer). As a result I have obtained acceleration from accelerometer on 3 axis, calculated net ...
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0answers
36 views
Simple Impulse Response DSP Hardware
I developed some complex chains of filters and crossovers. After that I have created IRs from the entire chains.
Applying these IRs in software works perfectly.
Now I wonder what is the easiest (and ...
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2answers
325 views
Impulse response of a second order LTI
I have a set of measurement which I want to model with 2nd-order difference equations (first order eqs don't model well enough).
The equation is
$$y[n] = \alpha_1 y[n-1] + \alpha_2 y[n-2] + \beta_0 ...
1
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1answer
131 views
How to convert multi-band Energy Time Curve (ETC) to Impulse Response (IR)?
I am running my own sound simulator. Now I have obtained the Energy Time Curve (ETC, expressed by energy) by physical simulation, and they are stored in 8 discrete frequency bands (because decay of ...
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281 views
What approximations are involved in STFT of a convolution?
I have two equations in time domain:
$$x_k(t)=\sum_{i=1}^N s_i(t)\star h_{ki}(t)+n^a_k(t)$$
and
$$x_k(t)=\sum_{i=1}^N s_i(t)\star h_{ki}(t)\star n^c_k(t)$$
which explain the additive and convolutive ...
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0answers
192 views
How to determine number of poles or zeros in prony's method?
I would like to use Prony's method for signal modelling. I want to design a filter such that its impulse response is equal to the message signal. I use the function ...
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192 views
What is a “Unit Shock” in an Impulse Response Function?
Is a "one unit shock" in an impulse function of variable "temperature" a 1% increase or 1 more "unit" (1 degree)?
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532 views
Inverse z transform - Pair of complex conjugate poles
How can I perform the inverse z-transform on the following $H(z)$ to be able to calculate a real-valued impulse response $h[n]$?
$$
H(z)=\frac{z^2}{z^2+0.8\sqrt{2}z+0.64}
$$
My idea was to find an ...
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0answers
81 views
Filter sharpening; a stub
Filter sharpening is a technique to sharpen the magnitude response of a digital filter. Finding information online about it is problematic since almost all google hits will be about image sharpening (...
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0answers
413 views
Problem implementing deconvolution to recover an Impulse Response
I’m new to DSP programming and I’m trying to learn a bit about convolution and deconvolution and FFTs. I have a project where I am taking a signal (a sine sweep) and convolving it with a shorter ...
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121 views
Describing a time delay at a maximum for maxima and minima but tends to 0 elsewhere
I have two force-time signals obtained from a couple of force plates, corresponding to input/output signals for some system. Plotting the two together one of the first things I noticed was a time ...
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1answer
308 views
Finding audio signal time delay: cross-correlation vs. impulse response?
I need to find a time delay between the two audio signals, one comming from one set of speakers, and the other being the source signal that is initialy sent to speakers. I send some noise through ...
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0answers
31 views
Deconvolution with noisy measurement of impulse response function
I observe a noisy 1D signal that has passed through some linear time-invariant filter:
$$z(t) = (h\star x)(t) + n(t)$$
where $h(t)$ is the filter, and I am hoping to recover $x(t)$. $n(t)$ is some ...
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0answers
32 views
Extrapolation of band-limited frequency data
I'm now studying "How to do accurate transform from band-limited frequency data specifically S-parameter data of high speed interconnect to the causal impulse response in time domain. There are ...
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0answers
14 views
Amplitude Matching for Exponential Swept Sine
I am working in the area of aerospace vibration testing and we use swept sine tests on structures and measure the response using the accelerometers. I tried implementing the technique "...
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0answers
14 views
Estimate IR's from single channel speech audio
I have a dataset of single-channel audios containing speech, recorded in a single room. I need to extract the room IR's. The goal is to simulate the room acoustics and adjust new speech audios ...
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1answer
32 views
If you would write the frequency-response in terms of projections through inproducts. How would you do it?
While studying for signals and systems I realised that the most intuitive way of understanding Fourier Series for me, was to see it as a projection (through inproducts) of a signal onto the orthogonal ...
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3answers
54 views
What do the function blocks mean?
What I don't understand is what exp(.) and ln(.) mean. For example y(t) and ...
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1answer
102 views
Impulse response from frequency response in Matlab
I am trying to design equalization filter and therefore I want to define my own amplitude and phase response and then to obtain the impulse response of the filter. I thought that the output of the ...
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0answers
53 views
Transfer function coefficients and impulse response - FIR filter
I am currently working on a FIR filter (varying in time). I have the real coefficients of the filter, but I would like to know if they correspond to the coefficients from the impulse response (as $b[k]...
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2answers
103 views
impulse response cascaded with time reversed of itself
Consider a filter with real-valued impulse response $h[n]$. The filter is cascaded with another filter whose impulse response is $h'[n] = h[-n]$, i.e. whose impulse response is the time-reversed ...
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1answer
85 views
Calculate Impulse Response of a System From Its Input/Output Waveform via FFT
From the theory, I knew something like :
$y(n) = x(n)*h(n)$
$Y(n) = X(n)H(n)$
$H(n) = \frac{Y(n)}{X(n)}$
Now I have $y(n)$ and $x(n)$ from a system, and $y(n)$ is 2176 samples long, $x(n)$ is 2176 ...
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2answers
44 views
How can i derive step response in terms of impulse response from the convolution sum?
If it is discrete LTI system,
How can i derive step response in terms of impulse response from the convolution sum?
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0answers
38 views
Characterizing a non-LTI system
How should we characterize a non-LTI system? For example we have: $y[n]=x[3n]+x[2n]+x[n]$ which is clearly not LTI. Also, the impulse response will be $h[n]=3\delta[n]$ and if we take the DTFT of this ...
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53 views
MATLAB- Add Envelope to Sound Signal
I’m in the process of making a convolution reverb and I’m trying to add an envelope to my impulse response signal and plot it in order to change the RT60 of my sound signal (Just a song). I’ve looked ...
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69 views
Relation between PDP (Power Delay Profile) and channel impulse response
I am traying to perform a simulation in Matlab and I faced up with some practical/theorical problems.
The channel I want to simulate is frequency selective fading. The packets are short compared with ...
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0answers
54 views
Phase response of an LTI-system
I've got an LTI-system such as follows:
$$y'(t)+{2} y(t)={5} x(t-{3}), t>0,
\\ \\ y(0)=0 \ \text{ ja } x(t)=0, \ t<0.$$
From this i've already figured out the transfer function:
$$H(f)=\frac{5\...
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0answers
39 views
FFT frequency-magnitude not correct when a positive gain EQ point is applied
I have a measurement system, which applies a log sine sweep as stimulus to a DUT and records the return signal.
I then extract the impulse response, and perform an FFT on this to examing phase and ...
0
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2answers
88 views
Impulse response of an infinite-length system
I have a system which is expressed as following:
y[n] + $\alpha$ y[n-N] = x[n] where y is the output and x is the input.
When I take the z-transform of both sides, I've found the transfer function ...
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1answer
62 views
I need to insert an underwater acoustic channel model to an existing code that compared between OFDM and GFDM
The acoustic channel model that I have will output the channel impulse response. However, my signal is modulated in frequency domain (by doing fft). Hence, I want to obtain a frequency response of the ...
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1answer
86 views
channel estimation for cdma
I am looking for a method to make a multi-user channel estimation with CDMA.
Here is my question:
Is there a way to estimate multi-user channels with their spreading codes? If yes, what is the ...
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0answers
812 views
BIBO Stability of an impulse response
I am trying to prove if $h_1[n] = 2^{-n} u[n]$ and $h_2[n] = (0.1)^n$ are BIBO stable or not, but I'm not sure if these analysis are correct. I'm having some trouble to understand this specific ...
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2answers
158 views
How do I show an impulse response leads to a zero-phase frequency response?
I'm trying to understand how to show that with real coefficients, the phase response of a filter is 0. Here is the impulse response
$h[n] = b_1d[n+1] + b_0d[n] + b_1d[n-1]$
How should I approach ...
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0answers
40 views
Applying the inverse FFT to even out a room's sound - What is the more efficient algorithm?
I have a way (the standard way) to correct for my room's acoustics, but I'm wondering if there's a more efficient algorithm, something that doesn't involve going to the frequency domain maybe?
I ...
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0answers
382 views
Smoothing the discrete acceleration
In order to know if my signal is increasing or decreasing, I'm using the discrete derivative $y[n] = x[n] - x[n-1]$
or a smoothed version of it (for example Exponential Weight Moving Average of $y[n]$ ...
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0answers
286 views
Solving linear system and find impulse response
I have this linear system that is defined by the differential equation
$$
y''(t) + 4y'(t) + 5y(t) = 2x(t) + 3x'(t)
$$
with x(t) the input and y(t) the output. I'm asked to find two things:...
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1answer
31 views
How to extract two signals from one signal by selecting right index?
Assume that we want to solve
$$AX=B$$
Where both $A, X, B$ are matrices.
I solved this by using ordinary least squares:
$$X = (A^TA)^{-1}A^TB$$
And I got this result for one column in $X$.
Here ...
-1
votes
1answer
533 views
Impulse Response of a Moving Average System
According to Discrete Time Signal Processing by Al Oppenheim 3rd Edition, the impulse response of a moving average filter is as below
My question is that shouldn't h[n] be having the dirac delta ...
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2answers
342 views
Shift-Invariance of Dirac Comb?
Is a dirac comb a Linear and a shift Invariant System? I could prove the linearity, but I do not think it is shift invariant. How do do I prove it is shift variant?
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2answers
316 views
Impulse response when input to a system is differentiated, and its applicability to find response to general inputs
I will first give a short explanation of what I am asking, and then give a more comprehensive context.
If we have a LTI dynamic system acted upon by inputs $y(t)$ and producing outputs $x(t)$,
,
we ...
