A discrete signal or discrete-time signal is a time series consisting of a sequence of quantities.

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How does time shift correspond to phase change in a discrete signal?

I was watching this video where the presenter remarks: For a discrete signal, time shift corresponds to phase change in a discrete signal but not vice versa. I was trying to figure out how ...
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16 views

Estimate the type of wavelet transform in receiver side

Suppose that a signal is decomposed by using discrete wavelet transform (DWT) and transmitted. Is it possible for receiver to find which type of wavelet is applied in transmitter side ? I mean, if ...
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74 views

Why would you use DCT as oppose to DFT for detecting oscillation in a signal?

For my project, I needed to detect the primary oscillation frequency in a signal data. As I googled around, it turns out that DCT is the best tool to find this ...
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25 views

Autocorrelation function of a discrete signal

For a certain experiment of which I have data, I want to calculate the autocorrelation of the measurements. For this I used the expression from http://en.wikipedia.org/wiki/Autocorrelation#Estimation, ...
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31 views

How to display the time frequency distribution [closed]

I have the basis atoms after decomposing the signal via matching pursuit algorithm. How do I now make a color plot of the time frequency distribution?
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1answer
44 views

Amplitude Spectrum, Nyquist Frequency, mixed/min/max wavelets

The problem is here. Now I know the definition of mixed/max/min phase wavelets, whether the roots lie within the unit circle or not. Starting from n = 1, let $$ x_t = ( 5, 6) $$ $$ X(z) = 5 + 6z $$ ...
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46 views

CWT for filtering / feature extraction

I had asked a question last night in regards to how to process my data (Noise rejection / feature extraction) but I have a more specific question now that I hope someone can answer. As mentioned in ...
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27 views

the importance of discrete sine transform

what are the applications of discrete sine transform . can discrete sine transform be used in place of discrete cosine transform ? please state the reason. can it be used in compression.? regards, ...
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1answer
62 views

Noise rejection / feature extraction

I'm hoping someone could point me in the direction of some signal processing methods to clean up my data. I'm collecting physiological data from human muscle (lower leg; gastrocnemius) during ...
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1answer
56 views

denosing given signal using wavelet

let us suppose that we have given following model $y(t)=A_1 \sin(\omega_1*t+\phi_1) + A_2 \sin(\omega_2*t+\phi_2) + A_3 \sin(\omega_3*t+\phi_3)+ \ldots +A_p \sin(\omega_p*t+\phi_p)+z(t)$ where ...
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71 views

LMS algorithm desired signal

I am working on LMS algorithm,i am not getting exactly how we get desired response of the filter that is compared with the estimated output
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11 views

Help in simulink for detecting specific parts of the signals

I am modeling some real-time ECG signals in simulink, and as I detect the zero-crossings or the peak of the pulse for this signal, I want to display the samples at which this occurs in the scope. This ...
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12 views

how to chose independent sample from a non linear regression problem

I would have a question concerning the first part of my assignment here below: (in bold) In this problem, the objective is to approximate a nonlinear function using a feedforward artificial neural ...
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1answer
32 views

How do I find the difference equation from a transfer function?

Most of the resources I found online go the other way. If I have the transfer function $H(z) = 1 - cos(\theta) \cdot z^{-1} + z^{-2} $ how do I get the difference equation from it so that I can ...
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37 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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20 views

get similar picture from wavelet transform

my today's question is related to previous question about wavelet, ...
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3answers
163 views

Store a FFT with a minimal amount of data

I have an array x of length 1024 (stored as 16 bits integers, named for example np.int16 in numpy/python), i.e. the size of x is ...
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28 views

Online FFT of simulated signal

it is a couple of weeks that I am thinking about the following: I have a tool which is able to simulate the dynamic behavior a steel tower exhibites due to the coupled action of wind and waves. ...
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39 views

Disadvantageous of wavelet transform

i have question related to wavelet transform:we know that while Fourier transform is good for spectral analysis or which frequency components occurred in signal,it will not give information about at ...
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1answer
54 views

Removing empty/low amplitude part from signal

I have a signal of length 'N' which looks like this ...
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108 views

can't find out the period of my signal

I've a noisy signal, which is the sound of motor with a constant speed, so the sound "should" be periodic, I know that there is a way to use the autocorrelation function to get the period,I did it, ...
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32 views

Coefficient Cancelation on Particular Solution

I am stuck on a problem about finding the complete solution of a Discrete Linear System by using the parametrization $y_{c}(n) = y_{h}(n) + y_{p}(n)$ where $y_{h}(n)$ and $y_{p}(n)$ are, respectively, ...
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61 views

Determining Valid DTFT's

Are the following frequency domain signals valid DTFT's (Discrete Time Fourier Transforms)? Answer yes or no, and justify your answer. a) $X(\omega) = \omega + \pi$ b) $X(\omega) = i + \pi$ c) ...
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2answers
62 views

Impulse Response with non-delayed feedback

I've been trying to solve a Discrete LTI System problem where the overall impulse response of the following System, whose input and output sequences are, respectively, $x(n)$ and $y(n)$, has to be ...
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39 views

Spectral leakage - understanding the integer number of cycles while windowing

I am reading tutorials about windowing and have read following sentence: For an integer number of cycles, all smoothing windows yield the same peak amplitude reading and have excellent amplitude ...
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2answers
133 views

Trying to understand downsampling and then upsampling

I am trying to understand how this works, specifically, what the DTFT of each step looks like in each step of the chain (for understanding). I am not looking for an answer like because the input ...
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1answer
41 views

How can I detect when a signal deviates from a flatline?

I apologize if this is not the correct forum, but I thought I'd ask. I have an array of signal samples and I want to detect (retroactively, once I have measured the time/magnitude values) if there ...
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1answer
41 views

Comparing 2 sinusoids: Discrete case vs Continuous case

I'm doing MIT's OCW course with Allan Oppenheim - "Signals and Systems". I'm given 2 continuous signals$$x(t)=\cos[\omega_x(t+r_x)+\theta_x]\tag1$$ and $$y(t)=\cos[\omega_y(t+r_y)+\theta_y]\tag2$$ ...
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91 views

How does amplitude scale when FFT size is smaller then signal duration?

I have one quite simple question: how does the amplitude of the signal scale when we do FFT where FFT window length is shorter then duration of the signal? Does this means that if FFT size is 12 time ...
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59 views

how to compare two audio signals

I have two audio signal that I want to compare using Matlab, my problem is that I can hear the difference between both loud and clear, but when use the function ...
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0answers
30 views

determining number of levels in discrete wavelet transform

I want to determine number of levels of decomposition of discrete wavelet transform when number of samples is not a power of 2 .I tried to decompose a signal of length 14 by using wavemenu of matlab ...
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23 views

Operaion on Simple Discrete Time Signal , Very Simple Question

I got this simple Discrete time signal question on which i have to perform shifting and multiplication.But I have some Doubt regarding the answer this book shows. Please see the uploaded image.
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1answer
35 views

how to process audio files in Matlab

I have project in which I'll work on audio files using Matlab, I'll be listing to different machine and should get thei rotational speeds, which is kind of periodic, my question how should I analyse ...
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1answer
43 views

can't get the right spectrum in scilab

I'm trying to write a simple script that should plot the spectrum in scilab, to test it I use a sinus function with 440hz so that I get my dirac in this position , my problem is that it doesn't work ...
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46 views

Confusion regarding Dimension of AR model

I have a confusion regarding what is meant by dimension of AR,ARMA,MA model? Considering an AR model $x(t) = a1*x(t-1) + a2*x(t-2)$ is a 2 order AR model with $a1,a2$ as the parameters. This equation ...
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14 views

Relationship between phase space volume and entropy minimization

I would like to know if there is any analytical proof or relationship which can show that for a dynamical system in presence of chaos signal, if the phase space volume (PSV) minimization leads to the ...
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1answer
44 views

How to calculate the zero state response?

In the following question and answer I kind of get it how it is calculated at surface but I don't get it fully. Can someone please explain the answer in depth?
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1answer
58 views

Matlab Neural Networks: input size vs. number of inputs

I'm trying to do time-series prediction with dynamic recurrent networks in Matlab (will try at least NARX and LRN architectures, if not one or two others). The question I have is, what is the ...
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3answers
128 views

Continuous time signal and discrete time signal

I know that all periodic continuous time signal have discrete spectral representations, but are all discrete spectral representations periodic in continuous time? Also, can all periodic signals be ...
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22 views

Why the number of poles and zeros for a RHS signal in the Z domain is equal?

I can not understand the reason why the following sentence is true: If we have a Right-Hand signal(RHS) x(n), X(z), the Z-transform of x(n), has the same number of poles and zeros except at z = ...
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1answer
112 views

eigen values and eigen vectors of signal

what does the eigen values and eigen vector of a signal or function represent ?what is its physical significance ?i came to know about basis vectors of a signal which constitute the orthogonal planes ...
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1answer
74 views

Scaling Property in DFT

In below image, we have scaling property of DFT, how the final equation is obtained from the above equation. That is how we are getting the scaling factor , $ \frac{1}{|ab|} $ in the final equation ? ...
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1answer
101 views

Exponential decaying Swept / chirp signal [closed]

I'm trying to create a chirp/swept signal that has it's frequency going down exponentially using matlab/octave. I can't use the built in chirp function because I'm trying to create a chirp/swept ...
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1answer
25 views

Measuring local “flatness”

I have a function which looks like so: I would like to know if there is a measure for a "weak type run length". How can I know that a function is approximately constant in some specific ...
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2answers
135 views

Why we need Frequency and Time information at the same time

The big disadvantage of a DFT is that it has only frequency resolution and no time resolution. This means that although we might be able to determine all the frequencies present in a signal, we do not ...
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27 views

How to acquire the `mainlobe` width to be less than the separation between two components that we wish to distinguish?

How does the mainlobe width of your window affect your ability to resolve the two components? Suppose a safe choice is to ...
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2answers
114 views

How do KLT and SVD differ from each other?

What are the differences between KLT and SVD? It looks more or less similar to me. Did I misunderstand the concepts? Explain me more about SVD and if possible provide me the link for SVD (Image ...
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2answers
87 views

Criteria to distinguish FIR and IIR filters from difference equation?

What criteria should be used to safely decide if it is an IIR filter or FIR filter from a difference equation? FIR filter are always stable, meaning all poles are inside the unit circle AND have ...
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1answer
53 views

Determing the frequency of a signal with a sample at a time [closed]

How to determine the frequency of a signal with a value of the sample and value of the time instant the sample was taken ?
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1answer
50 views

Why do we care about the multiplicity of poles and zeros in rational Z-transforms?

In the DSP class I'm taking, a lot of the questions ask me to list the multiplicity of a pole or zero in a rational Z-transform. For example, the multiplicity of the zero at $z=1$ in ...