Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [continuous-signals]

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

1
vote
0answers
12 views

Continuous-time RNN and Shannon sampling theorem

The most-used discrete-time RNN equations used in Deep Learning these days are those of Elman: I have seen two very different continuous-time version of these, with different justifications. The most ...
0
votes
1answer
24 views

Are the error probability of orthogonal signal and on/off signal the same?

I have to write the error probability of orthogonal signal and on/off signal,and now i have finished the error probability of on/off signal,but i don't know how to write the code about error ...
0
votes
1answer
23 views

Time Setting of $z$ and Laplace Transforms

I'm aware that the z-transform and the Laplace Transform have an analogous relationship but I want to be doubly-sure that the z-transform only works in discrete-time and that the Laplace transform ...
0
votes
0answers
11 views
1
vote
2answers
27 views

Confused in difference between sequence versus signal?

I am learning basics of signals and systems with MATLAB If i create a vector in matlab such that x=[ 2 5 10 20], will it be considered a sequence or a signal? As ...
0
votes
0answers
26 views

Detect the Beginning and Ending of a Signal

I have a signal that looks more or less like square wave signal with different phases (Like in the picture below). However, the signal fluctuates a lot, we can see in the image below: At first, I ...
0
votes
1answer
34 views

Consider the integrator and check for time invariance

I'm trying to check the following system for for time-invariance. $$ y(t) = \int_0^t x(\lambda) d\lambda$$ Please explain me why it is time-invariant.
0
votes
1answer
36 views

Confusion in linearity?

I am studying linear systems from the book "Signals and Systems Laboratory with MATLAB". I have performed an example on MATLAB myself in this regard. Code is as follow: ...
0
votes
0answers
22 views

Using MATLAB to plot the input and the magnitude spectrum of the signal

I have an aperiodic signal $v_{out} = e^{-t} u(t)$ (real exponential signal) from discharging capacitor. I was trying to plot using MATLAB 15 seconds of this signal in time domain? I am thinking how ...
0
votes
0answers
29 views

how can I know this system is Time invarient?

y(t) = 0 (t<0); x(t) + x(t-2) (t>=0); y(t) = 0 (x(t) < 0); x(t) - x(t-2) (x(t) >= 0); y[n] = x[n] (n>=1)...
0
votes
0answers
12 views

Can anyone please describe the relation between linear convolution and circular convolution? [duplicate]

It would be great if anyone could help. I am not able to find any relation amongst them, to me they are different things altogether.
0
votes
0answers
11 views

Is there any python code for applying a-law/mu-law on 3D numpy array?

I have 3D numpy array of probabilities between [0,1], I need to emphasize on some area with lower probabilities. I was suggested to apply a-law and mu-law. I am wondering if there is python library/...
2
votes
0answers
21 views

How to remove varying noise from strain data in MATLAB

I'm very new to signal processing. I have some data measured over time at 800 Hz. I'm interested in the high frequency signals. You can easily identify them in the image below (in this case, 3 signals)...
1
vote
0answers
13 views

Extracting signal from data using Otsu thresholding in MATLAB?

I am very new to signal processing. I am trying to extract a signal from my data using otsu threholding but it's not fully accurate. In this case I know that there is going to be a single signal in ...
2
votes
2answers
42 views

How to identify the beginning and the end of a signal using MATLAB

I have multiple signals as shown in this image. I'd like automatically detect time for the earliest detection of the signal (approx 0.7e4 in S1-B3-B (orange)) and last detected occurrence of the ...
0
votes
1answer
36 views

Area under waveform in t-domain including 2 delta functions

question: my attempt: $(a)$ $\displaystyle\int_{-\infty}^{\infty} f(t) dt=2 u (t)+r(t)-r(t-T)+Ku(t-T)$ then we draw it's diagram and found it was unbounded so,we doubt how area can be zero for any ...
1
vote
1answer
28 views

How would I find the function given the magnitude plot and the phase response?

I'm wondering how I'd find the Fourier Transform X(jw) given the following information: My understanding is that the expression for the continuous time fourier transform (CTFT) is magnitude(CTFT)exp(...
0
votes
1answer
28 views

Processing using Matlab

I'm new to Matlab.As a beginner, I want to work on few signals which are used in day today life and extract useful information through it. Can someone please help me from where I could start or share ...
1
vote
1answer
34 views

Confusion in the derivation of convolution formula [closed]

$$x(t)=\int_{-\infty}^{\infty}x(\tau)\delta(\tau-t)d\tau=\int_{-\infty}^{\infty}x(\tau)\delta(t-\tau)d\tau$$ Due to linearity, $$y(t)=T\{x(t)\}=\int_{-\infty}^{\infty}x(\tau)T\{\delta(\tau-t)\}d\tau=\...
0
votes
1answer
48 views

Are there any signals with brickwall autocorrelation?

Are there any signals whose autocorrelation $R(\tau)$ has the following form? Assuming $\tau_c > 0$ and $R_0 > 0$ a constant, $$R(\tau) = \begin{cases}R_0, \text{ for $|\tau| < \tau_c$} \\ 0,...
0
votes
1answer
34 views

Reason of effect of continuity and discreteness on periodicity of signal?

We know that a sine signal in continuous time is a periodic signal with a period $2\pi$ whereas the same sine signal in discrete time is aperiodic. My question is how changing just a type of signal (...
0
votes
1answer
24 views

response of LTI system to a Random Input Signal

what is LTI filter? what is the output when x(t) is input? let x(t) be the input signal to the system and y(t) denote the output signal. The output of the system may be expressed in terms of ...
1
vote
2answers
152 views

A question on Fourier Series and the frequency of the sinusoids

On studying about Fourier series, I encountered 2 doubts: How is it that a non-periodic function has a Fourier series? When expressing a periodic function as summation of sinusoids, why is the ...
-1
votes
3answers
44 views

How does real-time signal processing work when the signal we deal with is assumed to be known for all times?

One thing that never sat right with me after my signal processing course is that in order to do signal processing, we must know the entire signal $x(t)$. For instance, I cannot take the Fourier or Z ...
2
votes
2answers
80 views

DC value of $x(t)=\frac{1}{t}$

Is it possible to calculate the DC value of signals with undefinable area? More specificaly, in the case of $x(t)=\frac{1}{t}$. $\int\limits_{-\infty}^\infty\frac1t \, \mathrm dt$ does not converge. ...
0
votes
0answers
17 views

How does discrete spectral moment relate to continuous spectral moment?

It is said in discrete/digital signal processing that $r$th spectral moment of signal $x[n]$ is defined as: $$\sum_{n=-\infty}^{\infty}n^r x[n]$$ But how does this relate to usual continuous $r$th ...
0
votes
1answer
52 views

Effective Nyquist frequency / signal resolution for overlapping time averaged signal samples

Say that I have a continuous signal. If I sample the signal at sampling rate f_sample, then the highest signal frequency that I can resolve without worrying about ...
0
votes
2answers
35 views

Is there such a thing as a continuous phase BPSK?

My knowledge of signals and signal processing is limited, so I apologize in advance for my naïve and possibly confusing question. In the case of BFSK, the frequencies are altered to represent the ...
0
votes
1answer
69 views

Is there an example of an infinite signal? [closed]

In the real world, Is there an example of an infinite signal?
1
vote
1answer
37 views

Fourier Series Representation of Continuous-Time Periodic Signals [closed]

As a novice in signal processing, I have been going through Signals & Systems by Oppenheim to try and understand how continuous time periodic signals are represented by Fourier series coefficients....
0
votes
1answer
99 views

How can I get the continuous-time transfer function coefficients (or poles and zeros) from the corresponding discrete-time TF and vice versa?

Let's say I have a continuous time transfer function which I know its numerator coefficients $(B^c = [b^c_m, ..., b^c_1, b^c_0])$ and denominator coefficients $(A^c = [a^c_m, ..., a^c_1, a^c_0])$. ...
1
vote
1answer
114 views

Can a Fourier Transform exist even if the j$\omega$ axis is not in the Region of Convergence in it's Laplace Transform

A couple of confusions have been occurred. The Signal I'm considering is f(t) = sin(t)*u(t) Fourier Transform of it can be derived. $-i \pi (\delta (\omega -1)-\delta (\omega +1))$ According to my ...
0
votes
2answers
41 views

Simple problem regarding rectangular pulse shifting

So i have the following rectangular pulse: $$h(t)=\begin{cases} 1 & 0<t< T \\ 0 & \text{otherwise} \end{cases}$$ Now, i am supposed to create $h(T-t)$, and the ...
0
votes
1answer
42 views

Bandwidth of the Derivative of a Message [duplicate]

If I have a message signal $m(t)$ and it has a bandwidth $B$. I know that the bandwidth of $m^N(t)$ is $NB$. But what is the bandwidth of $\frac{d m(t)}{dt}$? Thanks!
-1
votes
1answer
52 views

Quite confused with Fourier Analysis results

So I'm meant to show how the DFT can find the frequencies, and respective amplitudes, associated to some data. And I have this data set from the curve $$ f(t) = 1 + 2\cos(2\pi t) + 4\cos(4\pi t) $$ ...
3
votes
1answer
52 views

Given a plot of both the magnitude $|H(\omega)|$ and its angle, How can you find the $H(\omega)$?

I'm specifically trying to use an inverse Fourier Transform to find $h(t)$, but I'm finding it difficult to get $H(\omega)$ in the first place. I'm under the impression from my textbook that $H(\...
0
votes
1answer
48 views

How to find the coefficients of the following differential equation

An arbitrary signal $v(t)$ pass through the following system, $w'(t) + 5 w(t) = v'''(t) + 320v''(t) + 40 v' (t) + 40v(t)$ How to determine the coefficients of the following differential equation, ...
0
votes
1answer
46 views

How to do convolution in Fourier Series?

Two signals are given to me : $$x(t)=\cos(4\pi t)$$ $$y(t)=\sin(4\pi t)$$ I have founded their coefficients as follows: $$a_k = a_1=a_{-1}=\frac{1}{2} $$ $$b_k = b_1=b^*_{-1}=\frac{1}{2j}...
6
votes
7answers
459 views

Intuition behind commutativity of convolution in LTI systems

Why is convolution commutative, as it seems to treat two signals in a different way in an LTI system? If you imagine $y[n] = x[n] \star h[n]$ with $x[n]$ being an input signal and $h[n]$ being the ...
0
votes
2answers
53 views

How will I draw the following signal?

I want to know that if I have any signal given how will I draw it according to the following equation $$x(t-1)-1/2$$ what will be the role of $1/2$ when drawing the new signal?
2
votes
1answer
81 views

Does the Fourier series coefficient of AC components remains same if DC component is subtracted form the given signal?

Suppose a signal is defined by $ x(t)= \begin{cases} t & 0\leq t \leq 1 \\ 2-t & 1\leq t\leq 2 \\ \end{cases} $ Since $x(t)$ has even symmetry, I can calculate fourier coefficient as $$ a_n = ...
0
votes
1answer
56 views

Energy of compressed signals

I have tried a code to compress a signal using Compressed Sensing(CS). The input signal is $x$ and the compressed signal $y$ is given by : $y=Φ*x$ where $Φ$ is the sensing matrix. I have used ...
-2
votes
1answer
33 views

Frequency component not filtered properly

Are frequency components other than wanted signal present in the output? If yes then why does it not disturb the original signal? I think all practical filter responses are not ideal, so all frequency ...
0
votes
1answer
85 views

Linearity of the given system

I am given the following system and I am checking the additive property: $$y(t)=x(e^t)$$ where $y(t)$ is the output and $x(t)$ is the input given to the system. Now this is what I did so far: \...
0
votes
1answer
29 views

Finding Harmonics Analytically

I've always obtained harmonics using simulation and never by hand. My question is how can someone find the harmonics for a signal (say a square wave) by hand? What equations come in handy for finding ...
1
vote
2answers
118 views

How to calculate the power of a finite length signal?

I am confused with these concepts. If the signal is expressed as r(t), I know the power of the signal is given by: But if the the length of signal T is finite and cannot approach infinity, how can I ...
1
vote
4answers
343 views

Difference Between Dirac delta and unit impulse function

The definition of Dirac delta function states that it gives a value of $\infty$ at t=0 and 0 elsewhere. But, the definition of unit impulse function states that it gives a value of 1 at t=0 and 0 ...
0
votes
1answer
23 views

identify equilibrium region after large transient

I am looking at data from a mechanical system under an unsteady load. I'm trying to find the simplest way to identify the portion of the signal once the system reaches its new equilibrium. Here's a ...
0
votes
3answers
224 views

What is the magnitude of the impulse function at t=0?

The unit impulse function, in a few textbooks that I have referred, has a value of 0 at t≠0 , and an area of unity (1). The height of the impulse function also tends to infinity at t=0. But since it's ...
0
votes
1answer
108 views

Show that any continuous-time signal $x(t)$ can be represented as $x(t)= x_e(t) + x_o(t)$

Show that any continuous-time signal $x(t)$ can be represented as $x(t)= x_e(t) + x_o(t)$ where $x_e(t) =\frac{1}{2}[x(t) + x(-t)]$ and $x_o(t) = \frac{1}{2} [x(t) − x(-t)]$ are even and odd ...