What is Signal analysis: Definition and 43 Discussions
Signal processing is an electrical engineering subfield that focuses on analysing, modifying, and synthesizing signals such as sound, images, and scientific measurements. Signal processing techniques can be used to improve transmission, storage efficiency and subjective quality and to also emphasize or detect components of interest in a measured signal.
Fitness function for window length of filter
On a sinusoidal signal with amplitude 1, and period P, an exponential moving average (EMA) (with alpha = 1/n), and a linear weighted moving average (LWMA) (with window length n) are calculated; when you subtract the EMA from the LWMA, it can be seen...
I am taking a class in signal processing. We have a final project in which we seek out "real-world" signal data and process and analyze it, and write a report on what we figured out. I thought it would be interesting to put my own interests into it and try to analyze a pulsar signal. My idea is...
Hi all. I am trying to do MATLAB simulations for generation of SINE Dipole using two hydrophones spaced distance 'd' apart for signal coming from direction 'DOA'. The MATLAB code is given below. The confusion is that there is constant phase difference of 90 degree b/w SINE Dipole generated using...
Hi all!
I have a complex waveform, something like what I have attached, and I need to extract the RMS and Peak Voltage from this. However, this signal can and will change after a number of cycles on a certain setting. So, this means the period and duration of pulse can change and so can the...
%My code:
%Type of signal: square
T = 40; %Period of the signal [s]
F=1/T; % fr
D = 23; % length of signal(duration)
dt=(D/T)*100;
N = 50; %Number of coefficients
w0 = 2*pi/T; %signal pulse
t1= 0:0.002:T; % original signal sampling
x1 = square((2*pi*F)*(t1),dt);%initial square signal...
My question is: is the resolving power of an array of radio telescopes a quantum or a classical effect? The increase in resolving power of a single telescope, as aperture size increases, is easy to explain in terms of Heisenberg's uncertainty principle. But when we go an array of telescopes are...
Ok, so in the interest of full disclosure at the outset, I'm a 69 y.o. retired epidemiologist who has an interest in HRV signal analysis specifically, and physics as a whole--always have. Am not an EE, physicist or mathematician so be kind, if you will. This is my first post.
In signal...
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...
I wanted to remove the dc component from a signal but i can't use the average method because i have only a half cycle sampled not a full cycle . Is there any algorithm or method that can remove the dc component using only a half cycle?
(The signal is sin(x)+2*sin (2x) +3*cos (3x)+4*cos (4x) +5...
<Moderator note: Moved from academic guidance to career guidance on Scott92's request. Reason: The question primarily addresses job opportunities in dependence of PhD subject.>
Hey everyone,
I'm a student who is currently undertaking a Master of Physics (coursework & research) at the...
[Moderator's note: This discussion has been spun off from another thread since it was getting into a more technical area only tangentially related to the original thread's topic. Some posts have been edited slightly for the new context.]
They're too technical for the question here, and only...
Hey guys, when you're linearizing a function that has a constant, what do you do to it?
An example would be y = x^2 + 3, would you just linearize it using its derivative and get rid of the constant?
hi, i am designing a fuzzy logic controller, i need to use a delay block for the change in error signal now i don't know that based on what factors should i choose the sampling time for this unit
I have a question regarding the time delay margin. I know the definition of time delay margin now I want to know that for the stability of the system is it good to have large time delay margin or small time delay margin?
Hi, May someone helps me regarding this!?
i have a controller which will control AC motor as attached. in this controller, a stage comes where I need to use a Derivative Block before point 'B' as shown in the attached picture " controller block diagram" [...
I have 2 PERFECT data of the transmitter and receiver. From 2 data, I can calculate the delay estimation:
Fs = 8e6; % sample rate
...
for i = 1:2
[cc_correlation,lag] = xcorr(signal2(i), signal1);
[cc_maximum, cc_time] = max(abs(cc_correlation));
cc_estimation...
Homework Statement
Let v(0) = [0.5 0.5 0.5 0.5]T, v(1) = [0.5 0.5 -0.5 -0.5]T, v(2) = [0.5 -0.5 0.5 -0.5]T, and z = [-0.5 0.5 0.5 1.5]T.
a) How many v(3) can we find to make {v(0), v(1), v(2), v(3)} a fully orthogonal basis?
b) What are z's coefficients of expansion αk in the basis found in...
Hi all,
in several vehicles, I measured the engine torque and speed and the engaged gear while it was driven for around 100km/h. I computed the average engine speed and torque of all the times the vehicle was run with each gear and also I computed the relative frequency of the gear used. So for...
So the question looks like this:
Identify the time and/or amplitude transformations that must be applied to the signal x(t) in order to obtain each
of the signal specified below. Choose the transformations such that time shifting precedes time scaling and
amplitude scaling precedes amplitude...
Hello there.
I am stuck trying to figure out the voltage gain of a cascode amplifier from a small signal analysis. The circuit seems to be under-determined for reasons I do not understand or maybe I am missing the perfectly obvious.
Here's my small signal model:
The only relation I can...
Homework Statement
I'm trying to calculate the Fourier Series for a periodic signal defined as:
y = x 0<x<2Π
y = 0 2Π≤x<3Π
Homework Equations
Fn = 1/T ∫T f(t)cos(kwοt + θk)[/B]
cn/2 + ∑k=1k=∞(cn)cos(kwοt+θk)
cn= 2|Fn|
θk=∠Fn
The Attempt at a Solution
I got Cn =...
Homework Statement
For a real, band-limited function ##m(t)## and ##\nu_v > \nu_m,## show that the Hilbert transform of
$$h(t) = m(t) cos(2\pi \nu_c t)$$
is
$$\hat{h}(t) = m(t) sin(2 \pi \nu_c t),$$
and therefore the envelope of ##h(t)## is ##|m(t)|.##
Homework Equations
Analytic signal...
I want to write a Matlab code which removes all frequency components from a .wav sound file except those within ##±25 Hz## of ##523 Hz## as well as its harmonics (up to the Nyquist frequency). I want to do this without using any built in filters.
Here is my code so far:
[s, Fs] =...
Homework Statement
I have made a plot of a given .wav file in Matlab. The problem asks: find the fundamental frequencies of the 3 vibrating strings, and identify some of their harmonics.
Homework Equations
3. The Attempt at a Solution [/B]
So I made a Matlab plot of the power spectrum over...
Hi all,
I have a signal and I need to check if it is stationary. I segmented a signal into different segments and for each I calculated the average value. It is enough to assess a weak nonstationary? Is there any limit value of the deviation of the average value of each segment with respect to...
In my electrical engineering textbook, they have an entire chapter devoted to the complex Exponential. I don't really understand it, nor do I understand its importance.
I know it is extremely important, and need to understand why, and what exactly it is, and the wording of the online resources...
Hi
I am trying to program excel to take the DFT of a signal, then bring it back to the time domain after a low pass filter. I have a code that can handle simple data for example
t = [ 0, 1, 2, 3]
y = [2, 3, -1, 4]
So I think everything is great and so I plug in my real signal and things go off...
Hi all,
I have 40 signals recorded on a vehicle. Some signals are analog and some are digital with 4 different states. One signal (I call it A) is really important to me, it is positive and all the other signals lead to its variability. For example, when there is a state change in a couple of...
Hi everyone! This is my first post here at PF after years of on & off lurking!
So, I'll get straight to it. At work (yes work, not HW) I have a forcing function signal that acts on a spring-mass system. When the spring-mass system "tracks" the forcing function, the curves overlap...
Hello, I'm having some issues with small-signal analysis of BJT differential amplifiers.
Let's say I have this BJT differential pair and suppose that Q1 and Q2 perfectly match: http://i50.tinypic.com/14ahdgn.jpg
Suppose a small differential input is applied and consider the small–signal...
Hello, I'm studying BJTs and I have a doubt about deriving the output resistance in the small signal equivalent circuit.
Let's consider the circuit below:
To derive the output resistance, I'd write the following KCL:
i_x = i_{rc} + i_c
at this point, every example I've seen says R_o = R_c...
Homework Statement
Hi ,
The problem is how to analysis this signal in terms of time segments to understnd the characteristics/pattern of this signal
Homework Equations
There is no relevant equtions
The Attempt at a Solution
I have tried to use :
RMS
Wavlet
FFT
But which...
Im taking This class EEL3135 and I am very lost and confused as to how to study or where to find resources to understand the material.
does anybody know of a good website for beginner signal analysis? or a good reference ebook etc to help me out with it? the ones i seen are far too advanced...
Homework Statement
Consider the signal x(t)=cos(4t)+cos(5t)+cos(6t), and the SLIT with impulse response:
h(t)=\begin{cases} 1, & \mbox{if } |t|<T \\ 0, & \mbox{if } |t|>T \end{cases}
For what value of T is the output of the system y(t) equal to Acos(4t)+Bcos(5t), when x(t) is the...
Homework Statement
The questions states to draw the output voltage (Vo) for two full cycles knowing that we have a sine source with 2v amplitude.
Homework Equations
The Attempt at a Solution
I've found:
Ic = 1.303 mA
Av (gain) = 1
I can't figure out why the output signal gets clipped...
With DFT/FFT/SFTF or similar Fourier transforms, there's always a trade off between frequency and time resolution. It's like the 'uncertainty principle' for signal analysis.
I have a few questions regarding this:
1: With a theoretical infinitely fast processor, is it possible to obtain...
Hi,
I am trying to get a plot of the sound's magnitude vs. frequency. I have managed to read in a wav file as a matrix. I then compute the fft of this matrix. When I plot the absolute value of this, I get a symmetric plot with peaks at the start and the end. What is this a plot of? Is it...
I don't understand why my book is saying that this system is not invertible.
y(t) = cos(x(t))
?
Wouldn't, arccos{ y(t) } = x(t) and therefore be an inverse system?
Ok I have this really simple question that is bugging me.
Lets say you have the signal:
y(t) = x(t-4)
where y(t) corresponds to the output, and x(t) the input.
I know this system is invertible, but I don't really know how to show that this is the case. I see that the output is x(t)...
Sorry, but I don't know where the topic about signal analysis should go..?
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I'm doing research about quantifying blood flow in the brain. Basically I need to know how to perform deconvolution (I think.)
I have two...