A continuous signal or a continuous-time signal is a varying quantity (a signal) whose domain, which is often time, is a continuum.

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1answer
23 views

Fourier transform of triangular function

Determine $X(\omega)$. $g(t)$: I understand how to create a box from [-1,1] of amplitude 1/2. $x(t) = g(t) * g(t)$ $X(\omega) = G(\omega)G(\omega)$ the solution I am seeing says that $G(\omega) ...
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2answers
47 views

“Perfect waveform” for cross-correlations?

I am well versed in cross-correlations, as my masters thesis heavily relied on them for music classification and beat detection. So this question focuses more on the signals that I am running an ...
0
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0answers
22 views

Continuum removal in spectral imaging

In reflectance spectroscopy, you often get curves like this one (blue line, x axis is wavelength in micrometers, and y axis is % reflectance): Usually, geologists use "continuum removal" to ...
0
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1answer
31 views

Extending a waveform

Apologies if this makes no sense or seems rather simple, I'm a Matlab newbie. Basically, I've got a .wav audio waveform which I am resampling to various different frequencies and then trimming the ...
1
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1answer
83 views

Why these harmonics always present?

I am using Audio Precision 2700 to test some test vectors. I have connected resistor banks as class - d power amp's load, and tap from this resistor using a XLR cable to the AP. When my power amp ...
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0answers
16 views

Time invariance and time variance [duplicate]

How can I write a MATLAB program that takes the given system described in terms input x(t) and output y(t) relations is input and finds out whether it is time-invariant or not?
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1answer
39 views

Usefulness of Matrix Notation for Linear Periodically Time-Variant Transformations

I am quit puzzled about a notation I found in Gardner's 1986 book titled Introduction to Random Processes. It is in the chapter on Cyclostationary Processes at section 12.4 which pertains to Linear ...
0
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0answers
18 views

What are some interesting things I can do with EEG data?

I have an EEG device and would like to experiment with it a bit. Some of the data I can read from the device, in real time, are: ...
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2answers
34 views

Spectral Content of two waveforms

I have found this interesting question here: Which of these two waveforms has a richer spectral content, and why? Intuitively speaking, I think that the first one is richer, but I cant really ...
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2answers
53 views

Generate a BPSK modulated signal with non zero mean [closed]

I want to generate a BPSK modulated signal with non zero mean. I don't know how to add a non zero mean.
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0answers
50 views

How can I simulate a broadband ultrasound transducer in Matlab?

I am using a Matlab model to send a broadband acoustic pulse across a fluid. The centre frequency should be 50kHz with 100% bandwidth. It has been suggested that I apply a window the pulse to ...
-1
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1answer
150 views

What are the advantages and disadvantages of the Ridgelet transform?

I used continuous wavelet transform (CWT) to analyze the behavior of a 1-D smooth signal(extracting its modal property, damping and frequency components)in my research. Now someone asked: Why the ...
0
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1answer
38 views

minimum frequency in periodic components

Suppose we have the following signal model $y(t) = A_1\sin(\omega_1 t+\phi_1) + A_2\sin(\omega_2 t+\phi_2) + ... + A_p\sin(\omega_p t+\phi_p) + z(t)$ When we are sampling at sampling frequency ...
4
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1answer
86 views

“chirp” with arbitrary period

Say you have a linear chirp, which is a bit like a sinusoid with a gradually increasing period, but instead of the linearly increasing period, could you pick an arbitrary value, like the red line in ...
0
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1answer
33 views

Using the windowing Method

I'm trying to write a C program that can get the PSD of an recorded audio file, I'm using for the fftw3 library. I wrote a program that calculate the PSD so far ...
3
votes
1answer
61 views

Sinusoid with increasing frequency

How would you describe this signal? It's like a sinusoid but as if its frequency was constantly increasing: could you write down a mathematical description? Thanks. And no, this is not homework...
2
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0answers
95 views

Convolving two complex signals - relationship between phase

Suppose two continuous complex domain signals are convolved, how is the magnitude and phase of the resultant signal related to the magnitudes and phase of the original signals?
0
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1answer
49 views

Counter design for audio signals

I am designing a schematic in which a Counter is to be increased whenever a particular band of frequencies is received at the Audio input. We are receiving the audio input as electrical Signal and I ...
3
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1answer
84 views

Why $x(t) = \cos(\frac{\pi}{3}t)$ and $y(t) = \sin(\frac{\pi}{3}t)$ are considered identical signals?

Consider the following question that I toke from Signals and systems: Part I exercises, question 1: (b) With $x(t) = \cos(\omega_x(t + \tau_x) + \theta_x)$ and $y(t) = sin(\omega_y(t + \tau_y)+ ...
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1answer
83 views

First-order low pass filter with bounded derivative

Given a function $x(t)$ and a first order low-pass filter $\frac{dy}{dt} = \frac{1}{\alpha} (x(t) - y(t))$, is there a way to choose $\alpha$ analytically such that the derivative of $y(t)$ is ...
1
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0answers
24 views

Statistics of the output of a high bitrate signal filtered through a narrow band low pass filter

I was wondering what would be the statistics of the output of the filtering of an extremely wideband signal (e.g. 10 Gbps random data stream) through a narrowband low-pass filter (e.g. 10 MHz LP). I ...
0
votes
2answers
200 views

If low frequency travels longer distance, why our speech is not travelling longer distance?

It is know that low frequency signals travel longer distance that of high frequency signal. If so, our speech signal is low frequency signal, why it is not travelling further?
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0answers
43 views

How to find blood pressure from osciloscope image

We have measured the human blood pressure with the sphygmomanometer connected to relative senzor of the pressure and osciloscope. We measured the offset of the sensor as $U_{OFF}=1.01\ V$ and the ...
2
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1answer
124 views

Auto or cross correlation for synchronisation in MATLAB

I have multiples records of a motor sound, I would like to synchronize them first and then calculate their spectrogram. My question is how can I use the autocorrelation or the crosscorrelation to ...
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2answers
36 views

Continuous time-domain electrical signal that only has a finite number of possible values

I have recently started learning DSP and the book that I am reading challenges the readers to find a: continuous time-domain electrical signal that only has a finite number of amplitude values ...
1
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1answer
103 views

Order analysis or order tracking

Last week I've been trying to implement the Order Analysis in MATLAB in vain. I've read a lot of docs about it like this one , but I still can't figure it out. This will be my last shot. Say I have ...
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2answers
216 views

Difference between band pass vs. low pass + high pass?

I am reading a paper in which they filter EEG signal using a notch filter to remove the power supply component of 50 Hz, then a high pass filter at 0.3 Hz to remove artifacts resulting from breathing, ...
1
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0answers
43 views

The order analysis in MATLAB [duplicate]

Can anybody tell me how to calculate the order analysis / spectrum of a signal? I've been searching in vain. I want to use MATLAB to analyse the signal / sound of a motor. For more information about ...
1
vote
1answer
90 views

How to analyse the sound of Motor

I have a motor, that I want to analyse, using its sound, so I can its 'character' I was using the the simple fft, and figured out, that it wouldn't help, so I tried the order analysis, at least I ...
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0answers
26 views

Matlab:Sampling Curve into Frames and Plotting

I have a Output Curve of following characteristics http://i.imgur.com/hABfsiC.jpg Following is the data which represents the output curve cited above ...
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0answers
33 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 ...
1
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1answer
122 views

Continuous-time mathematical formula for deconvolution filters

I have an elementary function $p:\mathbb{R}^2\rightarrow\mathbb{R}$ which (locally) represents an image. It's a polynomial, and its the result of the following 2D convolution: $$p=f\star G\star ...
0
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1answer
82 views

how to find the “Natural and Total Response” of the system

Hello there I am a Student. I need to know how to find the Natural and Total Response of the given system: where: $x(t)=e^{-t}u(t)$ and $y(0^+)=2, \dfrac{d}{dt}y(0^+)=3$. (If the image above is ...
0
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1answer
343 views

Convert normalized frequency to real frequency in AR model

Let us suppose that we have modeled signal using AR model, and suppose we have following model: I used spectral estimation function from MATLAB pyulear Now ...
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0answers
48 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 ...
1
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2answers
101 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 ...
1
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1answer
50 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 $$y(t)=\cos[\omega_y(t+r_y)+\theta_y]\tag2$$ ...
0
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1answer
29 views

Very Simple Problem regarding Shifting of Signal.

I Have this simple x(t) graph, and i have some confusion regarding time shifting. what is the graph of x(1-t) ?
0
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0answers
24 views

Finding Signal Energy of a continuous signal in the time domain

I have a quick concern regarding an assignment that I'm working on. Currently, to find the signal energy of a continuous signal, we're converting the signal to the frequency domain through a fourier ...
3
votes
3answers
295 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 ...
4
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1answer
126 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 ...
0
votes
1answer
62 views

adjusting swept signal equation

When I do a spectrogram in matlab / octave I can create a swept signal that looks like the RED plot line below. But how can I create a swept signal like the BLUE line in the 1st plot using the ...
0
votes
1answer
273 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 ...
-4
votes
1answer
90 views

How to calculate IDFT this signal? [closed]

$X(jw) = 1 + \frac {jw+3}{jw+4}$ what is the IDFT of this signal?
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2answers
84 views

Power of summation of two signals

Let $|A|$ denote the power of the analog signal $A$. Is that true to assume $|A+B|=|A|+|B|$, for two arbitrary signals $|A|$ and $|B|$? That is the power of the summation of two signals is -at least ...
1
vote
2answers
417 views

What is the difference between a one dimensional and a two dimensional signal?

If a signal depends on only one variable then we call it one dimensional, and if a signal depends on two variable we call it a two dimensional signal. But when we represent an one dimensional signal, ...
1
vote
2answers
194 views

What is the intuition behind convolution? [duplicate]

I have been using convolution for finding outputs of various systems .I know how to use it.But I still don't know what does convolution exactly means? how one can define convolution ?
0
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0answers
63 views

Relationship between fractional delay coefficients and frequency?

Some background: I am putting a sig-gen signal through an ADC, into an FPGA where I can modify it, out a DAC and up to a SpecAn. All that works fine. I am experimenting with fractional delay ...
0
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0answers
37 views

Screening out important signals

I want to know if there is a generalized way to select a signal from a set of signals. Let me clarify it: I have a number of signals $S = \{S1, S2, S3,...\} $. Some of the signals are not important ...
0
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2answers
73 views

Minimum number of points to specify a sine wave with a given accuracy

I am generating a sine wave from a DAC at a constant frequency. If each full cycle is specified by N data points what is the relationship between the accuracy of the rendered sine wave and N? N=1 ...