Frequency domain Definition and 49 Threads

I was wondering if anyone could walk me though a better explanation on how to get the given results for these two questions. The solutions posted by my professor aren't really clear to me so if anyone is able to better explain how to get the solution it would be much appreciated!

The time domain analysis is easier to plot compared to analyzing the frequency with respect to the phase. But, LTSpice makes it look really easy. So, for a small signal AC analysis, LTSpice does use a AC voltage source for its frequency domain analysis function. This must be a really convenient...

The circuit to be analyzed is shown below: Since initial conditions are zero (from the instructions) I will use laplace transforms for the cirucit and I will use the MAME method to solve this circuit. The laplace transforms that are required will give me: $$E_g(s) = \frac{10}{s}$$ $$ L_3 =...

Hello, I have a signal and got the FFT result of that. I have shown them both below along with the MATLAB code. May I ask if there is any method to find the time zone(s) in the signal that a specific frequency has(have) happened? The reason I'm asking this is that I want to specify the time...

Homework Statement Given the Fourier transformation pair ##f(t) \implies F(jw)## where ##f(t) = e^{-|t|}## and ##F(jw)=\frac{2}{w^2+1}## find and make a graph of the Fourier transform of the following functions: a) ##g(t)=\frac{2}{t^2+1}## b) ##h(t) = \frac{2}{t^2+1}\cos (w_ot)## Homework...

I am trying to implement several filters in Matlab for Fourier domain filtering. They are the cosine, Shepp-Logan, and Hann/Hamming window filters. These filters are defined as multiplying the ramp filter by the cosine function, sinc function, and Hann/Hamming windows respectively. This is how...

Hello All, I would like to convert a partial diff equation in time domain into frequency domain, however there is a term of the form: Re(∇(E1.E2*) exp(j[ω][/0]t)) where E1 and E2 are the magnitudes of the electric field and [ω][/0] is the angular frequency. Can someone please help me to...

Homework Statement Homework EquationsThe Attempt at a Solution So far I was able to transform each element into the frequency domain: I am just unsure how to work with the dots to find the mesh currents. Can someone explain? Thanks.

1) How many stages are in N numbers for a FFT? I know N=8 has 3 stages and N=4 has 2 stages ? 2) The DFT formula converts a signal from the time domain into the frequency domain. Is this done by comparing x[n] against signals known as sinusoidal basis functions? are e-j2 pi kn/N sinusoidal...

Assuming that a TLP platform is examined and the wave forces acting on the tendons of the mooring lines are presented in RAOs (as a function of wave frequency). Using Jonswap spectra for North sea (i.e peakness factor equal to 3.3) we can obtain Hs (significant wave height); Tp (peak period) and...

Hello, PF! I am currently learning Fourier series (and then we'll move on to the Fourier transform) in one of my courses, and I'm having a hard time finding motivation for its uses. Or, in other words, I can't seem to find its usefulness yet. I know one of its uses is to solve the heat...

Dear All, Suppose we have a electromagnetic/x-ray pulse with fixed energy with finite line width. I want to know the schematic of a plot how it looks in time- and frequency-domain? I think I understand in time domain: there will a straight vertical line on plotting intensity vs time in x-axis...

How to integrate $$\int_{-0.5}^{0.5} {\bigg({\frac{1}{4-2e^{-j2{\pi}f}}}\bigg)}^2 df$$

What is a frequency domain and how can we understand the same in practical world? How is it related to complex plain sight domain?

Hello, I'using Matlab to simulate phase shift in frequency domain (FD). I have got real and imaginary parts of the signal after FFT. I'd like to use phase shift in FD. This works: Y=fft(y); YY=Y.exp(-i*2*pi*nk/N*samples_delay); result=ifft(YY); But in my DSP I can't use the formula above and...

This is a soft question but I think it's a real fact.The Frequency domain has made revolution in the field of Mathematics,Physics,Digital Signal and image Processing etc. Some of concepts which are very difficult to analyse in spatial or time domain can be very easily understood in the frequency...

I understand that the Fourier transform maps one function onto another. So it is a mapping from one function space onto another. My question is, why is it often referred to as a mapping from time domain to the frequency domain? I don't understand why the image of the Fourier transform...

Hello people, i need help with frequency domain study in electric current shell modul. I have one IDC and i have electrodes from gold, and i don't know what should i do to see my frequency response on diagramm? Does anyone has any idea?

I'm working on a problem and one part of it is finding the zero-input response of a system in the frequency (or "s") domain. The zero-state response can be easily found in the frequency domain, it's just: Y_{zs} = X(S)H(S) But I can't for the life of me find the equation for calculating...

Anyone have an idea to find a first and second natural frequency from time domain and frequency domain plot resulting from an accelerometer measuring the vibration in cantilever beam ? Thanks very much :)

Can somebody tell me exactly what is 'S' in frequency domain? I know that s=σ+jw where σ is neper frequency and jw is complex frequency but i want the precise information on s you can suggest me a book in which it is clearly explained. Thank you.

Homework Statement Calculate the current in the capacitor shown if the voltage input is a. v1(t) = 10cos(377t - 30°)V b. v2(t) = 12sin(377t + 60°)V Give answers in both time and frequency domain. Homework Equations I = dQ/dt = C * dV/dt The...

Dears, I wish to measure the entropy of visual data such as image and video. I did transform these image and videos into frequency domain such as DCT, then measured the entropy with these pdfs for each AC components of image and videos. However, when I measured the entropy over spatial domain...

I am going through a past paper for an upcoming exam and I want to check that I am approaching this question correctly. H(s) = 1/(s2 + 8485.28s + 36x10-6) Calculate and plot frequency response for 0 rad/s, 500 rad/s, 1000 rad/s and 10000 rad/s. I am under the impression that the 's'...

Homework Statement Find the Fourier transform of the following signal JUST by using the FT table and the FT properties x(t) = sin(t) -pi<=t<=pi 0 otherwise NOTE: I am using CONVOLVED WITH as a substitute for * (the real convolution operator) because I cannot express...

Hi All, I'm just trying to practice graphing signals in frequency domain and I came across a stiuation I wasn't familiar with. If the exp() has a constant*t in it I'm not sure how to graph it, I remember that just cos it like a double sided exp(jwt) but with half the magnitude. I've attached a...

I need help understanding how frequencies are distributed when taking the FFT of an Image and how can i determine those frequencies, I really need a detailed and easy tutorial with practical example to understand it. When we take the FFT of a Sine/Cos wave we can easily see its frequencies in...

How will the graph of a sine wave (plotted against time axis) of a particular frequency look like if the same is plotted against frequency?

Hello, I need to sketch the frequency domain for the following AM waveform showing total bandwidth and frequency. 8sin(2pi500kt - 4cos(2pi530kt) + 4cos(2pi(470kt) I have attached an attempt I have made. Does anyone know if I have this correct or not ? Thanks kindly for any input.

Hello all, I want to filter DC offset for a signal by applying a high-pass filter to it (I've been told that to filter the DC offset this is what I should do - I'm not sure why exactly!) My question is; do I do that in the time-domain or frequency-domain after applying FFT? And I would...

I am studying Control Theory from Ogata. My math is a little rusty, so this is a math question about Frequency Domain Analysis. Check this page - http://www.flickr.com/photos/66943862@N06/6337116280/sizes/l/in/photostream/ I get everything upto Equation 8-4 However I don't get the line after...

Hi, I stumbled upon the following two functions which have the same freq domain representation, 1/(j.pi.f) 1.signum(t) = u(t) - u(-t) 2. 2u(t) what is the reasoning behind them having the same f domain representation?

Homework Statement Discrete-time transforms What does it mean when it says this : These transforms have a continuous frequency domain: Discrete-time Fourier transform Z-transform What is the meaning of continuous frequency domain..?

Apparently, when convolving, for example: [δ(ω-π) - δ(ω+π)] * (δ(ω+50π)-δ(ω-50π)) the result is δ(ω+49π)-δ(ω-51π)-δ(ω+51π)+δ(ω-49π) where δ() is the Dirac delta function, * the convolution operator and ω the frequency variable How do we get to this? Can you help me on the intuition in...

Hi, I am new to signal theory and don't know what is time domaine signal and frequency domaine signal. Please some can explaine me clearly and how can we convert between those two domaines. I read the topic in wikipedia which makes me somepart clear but interested to know...

Hey @ all, when windowing in DSP in time domain one multiplies all recorded time samples with a weighting factor (hanning, hamming, etc.), followed by a Fourier transform (FFT) to reduce sidelobes in the spectral domain. But now when thinking about starting up in frequency domain where I...

Homework Statement Sketch the z-plane pole zero diagram for: G(z) = \frac{z^{2} + z + 1}{z^{3}} Also sketch the time and frequency domain repsonses, the latter in amplitude and phase. Homework Equations G(z) = \frac{Y(z)}{X(z)} Zeros when Y(z) = 0; Poles when X(z) = 0 For...

hello, i am new here and this is my first post so please bear with me for any mistakes or so.. now my question is about time domain analysis and frequency domain analysis . why should one convert from time domain into frequency domain by using Fourier transform ? and what are...

how would wavefrom change change in time domain, frequency domain and its rms value if a dc level of 1 volt was added.

I'm trying to figure out what faraday's law is in terms of frequency rather than time. I think the equation is V = -N*B*A*2f. Where N is the number of turns in the loop, B is the magnetic field, A is the area and f is the frequency. However I am not totally convinced that my derivation is correct.

Hey guys, I am totally lost in the idea why we have to change function in time domain to frequency domain to ease with our calculations. Let me break my question into serveral smaller ones. 1)What is the physical implication of transferring a signal to frequency domain? (I know that in...

Hello everybody! I am trying to construct the FDFD method for 3D structures. I have already constructed the general formulation and specifically I have set the complete matrix form. Due to the fact that the matrices are too sparse, and my system is out of memory, I am trying to set the problem...

Does Cramer's rule work in frequency domain? For example, if we have to solve two simeltaneous equations, as in nodel analysis or mesh-current method, can we use Cramer's rule to solve em? Would this be an efficient method?

Hi, I've been trying to understand more on frequency plots of images. 1. Assuming a 1d example of just a strip of an image; in the frequency map there are 'same' no. of frequencies as there are pixels. What is the reason for this? Does this have something to do with the Nyquist theorom...

Hi everybody, I have question: Why can you do Convolution filter in the frequency Domain ? I mean, when you apply a filter to an image in the spatial domain, it 's easy. You've got for example your sobel 3x3 kernel that you apply on every pixel of your image. Easy. But when you convert...

How do you convert functions from the time domain, to the frequency domain For example: cos(250t + 30degrees) is what in the frequency domain? Are there some general steps I can follow to do this?

So...a cosine wave when shown in the frequency domain is represented by a 1/2 magnitude vector at the positive frequency and a 1/2 magnitude vector at the negative frequency. I am surprised by this because I cannot understand why a vector of magnitude 1 at the positive frequency of the cosine...

Aaah! - sin(wt) - time or frequency domain?! hi guys going a bit blank now... been thinking a bit too much about time and frequency domain to a point where I've confused myself a bit... The well known function: f(t) = sin(wt) It is evident that this expression is in the time...

I have a couple of questions regarding the representation of a signal in the frequency domain I wish someone could help me with.. 1-why is it when we represent a non-periodic signal in the frequency domain it is continuous while the frequency domain of a periodic signal is discrete ...