The impulse response of a dynamic system is its output when presented with a brief input signal, called an impulse.
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0answers
32 views
Practical impulse response estimation using NumPy
I would like to estimate the impulse response of a simple environment (room, two speakers, one microphone). I am aware of the issues/limitations of working with "near" LTI systems. That said, I have a ...
2
votes
1answer
62 views
Impulse vs Step response
What is the difference between an impulse and a step response diagram?
For example i have these two generated from the same filter:
What useful information we could retrieve from them?
3
votes
1answer
74 views
Impulse Response Question
For the differential equation
$$\frac{d^2y(t)}{dt^2}+\frac{3dy(t)}{dt} + 2y = x(t),$$
I was able to find the frequency response as $$H(j\omega)= \frac{1}{-\omega^2+3j\omega+2}.$$ However, I am not ...
2
votes
1answer
82 views
response of algorithm in non-equidistant time
We are investigating ways to test a control algorithm. The algorithm has a non-equidistant track of input data (i.e. not every sample is valid, and we know it), and should output a series of ...
3
votes
1answer
109 views
Group Delay of a system
Say I have an LTI system whose impulse response h[n] is:
$$
h[n] = \delta[n] + \delta[n-4]
$$
I want to find the group delay of this system. I know the group delay ($grd$) is defined as:
$$
...
2
votes
1answer
63 views
Intersymbol Interference — Root raised cosine filter redundant if doing impulse response equalization?
I'm implementing DBPSK (differential binary phase-shift keying) over audio (44.1kHz sample-rate) using software. Eventually I'll use multiple audio frequencies at once, so I'm using FFTs and inverse ...
5
votes
1answer
83 views
How to send / receive a short impulse in an extremely noisy signal with high timing accuracy?
I am pretty new to DSP. I need a computer to transmit data to a receiver through audio signals in a loud outdoor environment. (I am writing the software for both sender and receiver so I can design ...
4
votes
3answers
239 views
Recover filter coefficients from filtered noise
I have a digital signal which may be represented as a pulse noise source filtered with an FIR (finite impulse response) filter. Suppose that the noise consists of discrete pulses (nonzero samples ...
3
votes
1answer
162 views
Get an input signal from LTI system output, find impulse response
I just study signal processing and I have some questions.
How to find impulse response $h[n]$ sequence of the system if I have
$x[n]$ and $y[n]$ (input and output) sequences? Hope there is a formula
...
4
votes
0answers
59 views
Concept of finding forced response from difference equation?
I know how the process works, first from difference equation make a homogeneous equation and then find natural response , then find a particular response (in the form of input) substitute it back in ...
3
votes
1answer
199 views
How to identify impulse response of noisy system?
My lecture slides mention that two-level ("2-tasoiset" in Finnish) signals are good in identification with linear systems. I am trying to understand this in noisy system. I cannot find any method ...
1
vote
2answers
67 views
Obtaining the Impulse response from the frequency of a discrete system
I have the following discrete system's transfer function (Z domain):
$$h[z] = {z \over z - \frac{1}{2} }$$
I need to obtain the following:
The frequency response.
The impulse response.
The fourier ...
5
votes
0answers
122 views
Impulse Response / Frequency response Question
I have a major question. Please take a look.
I have this differential equation (DE):
$$
\frac{d^2y(t)}{dt} +\frac{dy(t)}{dt} +4y(t)= \frac{dx(t)}{dt} +2x(t)
$$
And I have to find impulse response ...
3
votes
1answer
147 views
How do I compute the impulse response of a robot?
I am trying to model a robot (my question in robotics.SE), so that I may train it using some reinforcement learning techniques. I was wondering if I can compute an impulse response of a four wheel ...
7
votes
4answers
473 views
Flipping the impulse response in convolution
During convolution on a signal, why do we need to flip the impulse response during the process?
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vote
1answer
73 views
Understanding the frequency scale of a spectrogram
The graph below was derived from a raw seismogram recorded during an earthquake over a timespan from t=0 to t=1400 seconds (not shown on x-axis).
The original seismogram $s(t)$ is not shown, but it ...
7
votes
2answers
119 views
Evaluating loudspeakers
If you don't have a lot of money to spend but you want to estimate the frequency response of different loudspeaker setups what is the best way to do it?
I bought a very nice microphone and built a ...
0
votes
2answers
111 views
Correcting large variable dc bias in signal FFT
I am somewhat new to signal processing, but i'm hoping I can provide enough information in order to be pointed in the right direction.
I am working on analyzing the frequency spectrum of audio signal ...
7
votes
5answers
634 views
Why do linear systems show sinusoidal fidelity?
I am looking for a proof for sinusoidal fidelity. In DSP we study a lot about linear systems. Linear systems are homogenous and additive. One more condition it satisifies is that if a signal is a sine ...
6
votes
2answers
324 views
Does this lowpass filter have a noncausal impulse response?
I'm doing some measurements with my sound card, I have one output channel connected to one input channel.
I then send the sound card a unit impulse, i.e. a signal 1 value followed by zeros.
The ...
5
votes
2answers
364 views
Complex impulse response functions?
I think I must have misunderstood something regarding the relation between impulse and frequency responses.
I have calculated the Impulse Response Function, IRF, from the Frequency Response ...
8
votes
2answers
272 views
What bandpass filter design will yield the shortest impulse response?
Designing a simple 2nd order IIR bandpass Buterworth filter with a centre frequency of 500 Hz and a 1 octave bandwidth gives me the following frequency response ...
Now, if I take the impulse ...
5
votes
3answers
224 views
Rough estimate of how close a human speaker is to a microphone?
Is there a known technique for estimating how close a human speaker is to a single microphone? I'm hoping that there is a known technique that can analyze an incoming audio signal that contains a ...
3
votes
1answer
120 views
modelling wireless multi-path channel - is channel response sum of delta(t-path_delay) or “delta” should be smoothed somehow?
Consider the wireless channel. It is mult-path - means that signal is sum of sent signals with some delay and fadings.
The standard models for "impulse response" for multi-path channel in wireless is:
...
2
votes
1answer
259 views
Help finding the output for input with conditions
I'm trying to find the output where $h[n]$ is the impulse response of a real stable causal LTI system, and $s_0 \epsilon \mathbb{R}$, and where the input is $x[n] = e^{2\pi i n s_0}$ for $n \epsilon ...
0
votes
1answer
67 views
Formula to compute output of a linear system
The impulse response is $h(t)=e^{-t}u(t)$ and input signal is $x(t)=1 + \frac{1}{2}cos(400πt)$
I want to find y(t)..
I tried to use $\int^{\infty}_{-\infty} h(τ)x(t-τ)dτ$ ,however i know that ...
16
votes
4answers
7k views
What is meant by a system's “impulse response” and “frequency response?”
Can anyone state the difference between frequency response and impulse response in simple English?
6
votes
2answers
431 views
How to estimate the number of taps needed for subsequent channel estimation algorithms?
I recently implemented an MMSE channel equalizer, and I have read about many other types of channel estimation/compensation algorithms out there. However, one thing that is never talked about it how ...
7
votes
1answer
631 views
How do I find a system's impulse response from its state-space repersentation using the state transition matrix?
Suppose we have a linear represented in the standard state space notation:
$$ \dot{x}(t)=Ax(t)+Bu(t)$$
$$y(t) = Cx(t) + Du(t)$$
In order to get its impulse response, it is possible to take its ...
