Signal Processing Stack Exchange
Signal Processing 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.

In case of a continuous signal, the function's domain is an uncountable set. The function itself need not be continuous. To contrast, a discrete time signal has a countable domain, like the natural numbers.

Source: Wikipedia.

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Does the inverse-CTFT exist for a dirac delta?

Does the inverse continuous time Fourier transform exist for a Dirac delta (A single causal/non-causal spike)?
Mikhail
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Are there any advantages oversampling?

Are there any advantages of undersampling or oversampling in signal processing point of view?
aan
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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. Does that mean that its DC can not be determined?
Manouil
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Estimate input from measuring only RC filtered input

I am interested in knowing the step amplitude on a signal which can only be measured through a hardware RC filter. The measured signal follows this formula: $$ V(t) = V_0 \left(1 - e^{-\frac{t}{RC}}\right) $$ Is it possible to estimate the step…
Vandhunden
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What would be an example for a continuous signal from "daily life"?

Please share an answer with a simple example from the "daily" (colloquial) lives of humans for a signal which is "continuous" and explain what is it that rigorously makes it "continuous". Please use the simplest language you can, as if you would…
Alkalix
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What happens when we oversample?

I had an interview for a wireless communication position and one of the interviewers asked me this question in regard to signal processing. If I have signal and I sample at the Nyquist frequency and then it goes through a quantizer and if we have…
Tyrone
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How do I use the step and ramp functions to create a specific signal?

I am trying to figure out how to use the step $u(t)$ and ramp $r(t)$ functions to create the function $f(t)$ below: $f(x) = \begin{cases}0 & \text{for } t < 0 \\ t & \text{for }-1 \lt t \lt 1 \\ 2 & \text{for }t \gt 1 \end{cases}$ The step function…
user1068636
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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 $y(t) = sin(\omega_y(t + \tau_y)+ \theta_y)$, determine for which of the following…
user10293
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When discretizing a stochastic signal , are there random variables independent of those that follow in time and dependent on previous ones in time?

$X(t)$ is a stochastic process defined on the time interval $(0, T)$. Discretizing the time interval one specify the time instants $t_0=0 < t_1 < t_2,\cdots,< t_{n-1} < t_n = T$. A random variable $X(t_i)$ may be considered as being dependent on the…
Adrian Daniliuc
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How is $u(at+b) = u(t+b/a)$ for $a>0$ and $u(-t-b/a)$ for $a<0$?

I've come across this equality that I don't know how to prove. I've tried using the delta function due to its relationship to the step function, but I can't reach any results.
Anna Smith
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Inverse Continuous Wavelet Transform off by constant factors

I am implementing a continuous wavelet transform and its inverse using morlet wavelets. When I compute the inverse, the resulting signal is off by some constant factor (but otherwise correct). Depending on which frequencies of wavelet I use for the…
user63598
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What's the value of the integral $\int_{-4}^{4}(\frac{\mathrm{d}}{\mathrm{d} t} \delta(2t))\sin(t)\mathrm{d} t$ ..where $\delta(t)$ is the Dirac delta

Can it be solved like $$\begin{align}\int_{-4}^{4}\frac{\mathrm{d}}{\mathrm{d} t} \delta(2t)\sin(2t)\mathrm{d}t &=\frac{1}{2} \frac{\mathrm{d} }{\mathrm{d} t}\int_{-4}^{4}\delta(t)\sin(2t)\mathrm{d}t\quad ^*\\ &=\frac{1}{2} \frac{\mathrm{d}…
Ajay
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Adding/subtracting sinusoids

I'm trying to calculate resultant function from adding two sinusoids: $9\sin(\omega t + \tfrac{\pi}{3})$ and $-7\sin(\omega t - \tfrac{3\pi}{8})$ The correct answer is $14.38\sin(\omega t + 1.444)$, but I get $14.38\sin(\omega t + 2.745)$. My…
Bord81
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Different definitions of unit step signal

While I was learning signal theory, I have come across different definitions for the unit step signal. For example. $u(t)=\begin{cases} 1 & t\geq0\\ 0 & t<0\\ \end{cases}$ $u(t)=\begin{cases} 1 & t>0\\ 0 & t<0\\ \frac{1}{2} &…
JaalaP
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Help in sketching a CT signal with discontinuities

This is the Original signal: And I'm supposed to sketch $[x(t) + x(-t)] .u(t)$ I know that unit step signal will make the signal starts from 0 to $+\infty$ My problem is at key point (0) and key point (1)
Hossam Houssien
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