Questions tagged [periodic]
The periodic tag has no usage guidance.
162
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Separating 'heart sound' from 'lung sound'
I have audio files recorded from electronic stethoscope and in those files I want to filter out heart sounds and retain just the breathing sounds. How can I do this using just the signal processing ...
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Magnitude and phase spectrum of a periodic signal
Let the following T-periodic signal :
I found that
$$ x(t) = \frac{A \cdot t}{T} \qquad 0 \le t < T $$
and its Fourier series is :
$$ x(t) = \frac{A}{2} - \frac{A}{\pi} \sum_{n=1}^\infty \frac{\...
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producing sine signal with few samples
I need to produce a signal of $\sin(2\pi\cdot 60\cdot10^6 t)$, where $t$ in sec, with sample rate of $2^{28}$ Hz.
Since the signal has period of $\frac{1}{60\cdot 10^6}$ sec can I somehow sample only ...
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How to separate Transient and Steady-State Expression from Periodic Summation Response?
Background
My question comes from here, it's a response of 1st order LPF RC circuit from an arbitrary periodic input.
How to determine the transient response of a circuit to causal periodic inputs?
...
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Can time aliasing cause peaks?
For the following I use the terms “time domain signal” and “frequency domain signal” as a Fourier Transform pair. The question is for generalized cases of continuous-time signals that once sampled in ...
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Is there any method to incorporate boundary periodic conditions into the kernel summation over unstructured data points?
Supposing that there are $N$ particles distributed inside a periodic cubic box of volume $V=L^3$, I want to divide the cube into a regular mesh and calculate the following summation at each grid point ...
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How can i get a growing sinusoid in matlab?(by incorporating real part into exp command besides imaginary part which is already there)
I am trying to display a growing sinusoid in MATLAB and i know that imaginary part corresponds to oscillations but i am confused how can i incorporate real part in ...
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Finding periodicity in discrete events II - missions to Mars
Per the Space Exploration SE question Are launch windows to Mars avoided if they result in landings during dust storm season? the synodic period of the relationship between the motion of Earth and ...
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Is the unit step function periodic?
I am confused regarding the unit step signal. Is it considered to be periodic signal or non-periodic signal?
In MATLAB we use command heaviside to implement it ...
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How to detect the end of a period of a repeating pattern in some time series signal
I have an incoming stream of time-series data which looks like in the below figure :-
I want to detect the end of each cycle in real-time (marked with red arrows) using C language. What would be the ...
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is this signal is perodic?
What is the time period of
$$ x(t) = 7 e^{\jmath(5t + \pi/2)} + 10^{\jmath(7t + \pi/5)}$$ ?
X(t) is the combination of two functions. one is the natural logarithm base, $e$, and the other is 10.
if ...
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If I have this discrete time sinusoid composed of a sine and a cosine, how do I find its period?
$$ x \left[ n \right] = 3 \sin \left( 4 \pi n \right) + 2 \cos \left(0.36 \pi n \right), ~~~ 0 \leq n \leq 100 $$
The fact that my signal is composed of both sine and cosine makes it tricky for me.
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What would be the fundamental period of this discrete-time signal?
Question: $x[n]= 3\cos(0.3\pi n + 0.1) - \sin(0.11\pi n -\frac{\pi}{3})$ Find the fundamental period for this discrete signal.
My attempt: Write the two functions as:
$$\underbrace {3\cos\left(\frac{3}...
user64710
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Fourier transform of periodic functions
The Fourier transform is derived from the Fourier series by considering a non-periodic signal, thinking of it as a infinitely long periodic signal, putting it into the Fourier series and making this ...
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How do I determine if the fundamental period $T_{x}$ exists and if so what it is?
I recently came across this
$$ x(t) = \cos(6t) + \sin(8t) + e^{j2t} $$
signal that I want to find the fundamental period $T_{0}$ and fundamental frequency $\omega_{0} = 2\pi f_{0} = \frac{2\pi}{T_{0}}$...
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Period and wavelength of a noise signal?
How do I determine the wavelength of a noise signal like the one below? I find it easy to understand for sine waves, but it gets tricky for me when the signal is more complex like a noise signal.
If I ...
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Is there any rule of thumb for determining periodicity of a signal just by observation of mathematical expression?
Is there any way(rule of thumb) to determine periodicity of a signal just by observation of mathematical expression as rule of thumb mentioned in attachment for determining time invariance of a system
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How to calculate frequency of a periodic signal?
I know there are similar topics but I can not find any solution in my situation.
I have an accelerometer sensor and a basic microcontroller. Accelerometer data is collected in an array via i2C. I want ...
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Difference between time period formulas? Continuous time vs discrete time?
For calculating period of continuous time signal,we simply divide 2pi by omega and get period value
But in case of discrete time signal, procedure is not straight forward like continuous time, ...
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does T = 1/F always hold?
i just want to know if i use a sampling frequency of 100-110Hz and get a useful signal frequency of 50Hz (because of Nyquist–Shannon sampling theorem), is the period 1/50Hz or 1/100Hz?
I've been told ...
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How can I check if a signal its periodic from the graph of FFT?
x is a vector of length 1000 that contains the samples of the signal;
n is equal to 16 that its the number of bits of each sample;
fa=256 Hz (sampling frequency);
<...
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Fourier Series of a piecewise function
I've been given the task to find the Fourier Series Representation. All I'm given is this $$x(t)= \begin{cases}-t & \text { for } 0 \leq t<1 \\ 1 & \text { for } 1 \leq t<2 \\ 0 & \...
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Fourier transform of shifted periodic function
Assuming $x(t)$ is a periodic function of period $T$ and having the Fourier transform $X(\omega)$, it is required to calculate the Fourier transform of the signal $x(t)+x(t-T)$. Since x(t-T) is equal ...
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Prove Convolution Property for DFT using duality
If $x_1[n]$ and $x_2[n]$ are finite length sequences of length $N$
$$\mathcal{DFT}(x_1[n] \circledast x_2[n]) = X_1[k]X_2[k]$$
where $X_1[k]$ and $X_2[k]$ are the DFTs of$x_1[n]$ and $x_2[n]$, ...
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Prove Discrete Time Fourier Series Multiplication property
Note: This is not a homework problem. I'm just stalled at a point because I think I might be interpreting the duality property incorrectly.
If $x_1[n]$ and $x_2[n]$ are periodic with period N, then if ...
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How does this periodic signal look like?
I'm very new to DSP, and I'm unsure about finding how a signal $y[n]$ would look like. The following is given:
Assume we have a finite support signal $x[n]$ which has the values $1, 2, 3$ for $n = 1, ...
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What is a "pitch period"?
The term pitch period appears in the book Speech and Language Processing by Daniel Jurafsy:
As we just said, a pitch-synchronous algorithm is one in which we do
something at each pitch period or ...
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Is a continuous time aperiodic signal discrete in the time domain?
This is a statement I have read from a textbook:
Whenever we have periodic signals continuous or discrete time the frequency domain is discrete and time domain is continuous.
Whenever we have ...
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Angular frequency of discrete signal
Can someone explain me how to obtain the angular frequency here?
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Why is $x[n]=\sin(\frac{12\pi n}{5})-\sin(\frac{2\pi n}{5})=0$
I was trying to find the period of $\sin(\frac{12\pi n}{5})-\sin(\frac{2\pi n}{5})$, each of the sinusoids has a period of 5 however their difference has a period of 1. It turned out that they're ...
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Periodicity of complex exponential in continuous and discrete time (Eq 1.51, Signals and Systems by Oppenheim & Wilsky)
Hi All: This is very basic but I've always wondered about it and now I see it in print in a textbook so I may as well ask. In Signals and Systems on page 26, it says
$$e^{j(\omega_0 + 2\pi)n} = e^{j2\...
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confusions regarding periodicity?
I have a sequence $x[n]=\sin(\pi n+2)+\cos(2n/3 +1) $
I want to find its period and I have also attached my working
I have two confusions
Is there any effect of the constant term on period? constant&...
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What is "filter periodization"?
A library defines periodize_filter_fourier, which is an equi-spaced averaging formulated by
$$
v_f[k] = \sum_{i=0}^{\text{n_periods}-1} h_f[i\cdot N + k],
$$
where $v_f$ is periodization of $h_f$, $N=\...
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Fourier series of cycloid
What is the Fourier series representation of a cycloid?
The parametric representation of the curve is as follows.
$$
t=\dfrac{\theta-\sin\theta}{\pi}\\
x=\dfrac{1-\cos\theta}{\pi}
$$
The period is $2$...
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Good test for periodicity between signals
I have two timeseries signals. They look like this:
Each signal started out from the same array, but each received different preprocessing treatments. Ultimately, each signal represents the breathing ...
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Is it important to learn to find de period of the sum fo two DT signals?
The fundamental period (N) of the sum of two DT signals could be the LCM of the fundamental periods. However, this is not always the case. I would like to know wether, during engineering design or ...
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Calculate periodicity of audio signal
I have to calculate the periodicity of a audio signal like this:
You can see by eye, that the volume rises the highest every second "blob".
The spectogram (that is visualized ...
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Detecting periodic components in discrete-time signals [closed]
I am looking for real data examples where it is of interest to detect the presence of a periodic component of some discrete-time signal when the period of the periodic component is not known.
Suppose ...
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What is the value of the given periodic signal at any time, how to solve it in MATLAB?
Firstly hello all, I need help about periodic signals. I have a question as below.
$x(t)$ is a periodic signal and $0.1t^3[u(t) - u(t - 7)]$
describes its one period.
What is the value of $x(t)$ at ...
user54398
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What should go to infinity in power's formula N or the repetition KN?
I have this question :
I should now calculate power of y[n], where the formula
well in the power's formula N which constant goes to infinity how could this be ?
i see in the question that N=7 which ...
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Why in formula of power of periodic signal is $2N+1$?
Where does $1$ come from, like from $-N$ to $N$ is $2N$ so why is $2N+1$?
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Finding Fourier series coefficients for discrete time signal
Let $x[n]$ be a periodic sequence with period $N$ and Fourier series representation $$x[n] = \sum _{k=<N>}a_ke^{jk\frac{2\pi}{N}n}$$ Determine the Fourier series coefficients for
$$y[n] =
\...
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Periodic signals in Continuous and discrete time
Is there any signal which is periodic in Continuous Time but not in Discrete Time?
I have this doubt prevailing in me for a long time.
Are all CT periodic signals periodic in DT?
If so, how is sin ...
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Autocorrelation for periodic signals
Autocorrelation for power signals is defined by $$R_x(\tau)=\lim_{T\to\infty}\frac{1}{2T}\int_{-T}^Tx(t)x^*(t-\tau)dt\tag{1}$$ Is it true that for periodic signals $(1)$ can be computed by $$R_x(\tau)=...
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Fundamental period of $x[kn]$
Let $x[n]$ be a periodic with fundamental period $N$ and $y[n] = x[kn]$ where $k \in \mathbb{N}$ and $k\ge2$. Is $y[n]$ periodic? What's the fundamental period of $y[n]$?
Here is my answer:
If $N = ...
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Change in frequency on differentiation
Is there any possible periodic signal can exist(even mathematically) whose period gets change after differentiation?
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Duality in the discrete-time Fourier series
Suppose $g[n]$ is periodic with fundamental period $N$ and $f[k]$ being its Fourier coefficients i.e. $$ f[k] = \frac{1}{N}\sum_{n=<N>}g[n]e^{-j\frac{2\pi}{N}nk}$$ In more convenient notation $$...
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Ideal low pass filter output at given sampling frequency
Consider the signal $\cos(30t)$ sampled at $w_s=40 rad/s$ using a unit impulse train. The sampled signal is filtered with an ideal low pass filter with unity gain and cutoff frequency $w_c = 40rad/s$. ...
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Existence of finite output of a system [closed]
1.If frequently response of a LTI system exist and finite then can we say that, for a periodic or non periodic input signal, output is also finite?
2.if responses(output) of LTI
system for ...
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$2\pi$ Periodicity is not working for me for Fourier of Discrete Time Signal
please help me find the error in the following counter example.
Consider we take sinus with period of $2\pi$. We sample it many time, and more than 3. We make convolution with rectangle of height 1 ...
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