Skip to main content

Questions tagged [signal-analysis]

The processing of signals for the purpose of extracting a parameter or property embedded in a signal. Signal goes in and far fewer numbers come out.

Filter by
Sorted by
Tagged with
0 votes
0 answers
11 views

I want to generate a real time fft of vibration data from a triaxial MEMS accelerometer

I have been trying to generate a real-time FFT plot for my final year project on Condition Monitoring using a MEMS accelerometer (an MPU 6050) and an Arduino UNO. My goal is to generate a real-time ...
JONATHAN SEQUEIRA's user avatar
0 votes
1 answer
48 views

Is the analytical fourier transform of an exponential decay the same as the FFT of a time series of the same signal?

Analytical Fourier Transform of $e^{-t/2}$: FFT of a time series representation of $e^{-t/2}$: I'm trying to find the decay coefficiencts in tri-eponential decay signals, and as a logical starting ...
Oliver Nicholls's user avatar
0 votes
1 answer
39 views

How single-tap equalization can be performed in OFDM for perfect channel estimation?

If I have for example IFFT length of 3 with cyclic prefix length of 2 and 3 channel taps, how can I illustrate the frequency domain equalization in OFDM? For example as far as I know, it's elementwise ...
Amitabha Bhattacharjee's user avatar
1 vote
0 answers
34 views

ML-Classification of Motor Imagery EEG data only at 50% in MatLab

I'm trying to do ML-classification on some Motor Imagery EEG data and for a long time now I've been stuck at ~50% being correctly classified. This is my first time working with EEG data and signal-...
Chraller97's user avatar
1 vote
0 answers
42 views

How to improve quality of the recovered image in compressed sensing technology?

I was trying to use compressed sensing technology in image processing. Basically, I did a code in Python(Spyder IDE) which takes an image, compress the image and reconstructs it. I tried with the ...
Anya's user avatar
  • 11
1 vote
1 answer
85 views

Removing DC bias

I have a signal that I have recorded from a AirSpyHF and want to remove a unwanted narrow signal with a notch filter (see figure). The spike in the image below appears to be a center spike, however it ...
Al Grant's user avatar
  • 131
0 votes
0 answers
34 views

Generating a whitening filter using MATLAB cceps() function

I have a few thousand realisations of a discrete stochastic process. I am trying to generate a whitening filter from these realisations. I am expected to use the MATLAB cceps() function to generate ...
SumDood's user avatar
0 votes
2 answers
55 views

Can Autocorrelation be used to Differentiate Signal Quality (High, Medium, Low, Very Low) for Periodic Signals?

I'm working on a project to classify the quality of periodic signals into four categories: high, medium, low, and very low (noisy). I was initially exploring autocorrelation as a potential feature for ...
Mamad Fasih's user avatar
0 votes
2 answers
95 views

How to remove known noise from acquired signals

what is the question: I have some time sequences(sampled at 0.5s and 3kHz which means every one of them has 1,500 points) from my force sensor. But I find the signal fluctuates wildly under no load, ...
Erdong111's user avatar
0 votes
0 answers
32 views

Getting amplitude from messy signal

I'm working on analyzing some data from a grain boundary in an atomic simulation. I've got a lot of similar data to go through and am trying to determine a reliable way to get the amplitude of my ...
Kenefactor's user avatar
0 votes
0 answers
31 views

Can I get a resonance frequency from FFT power spectrum result?

I'm going through vibration analysis of cantilever by using FFT device but impact hammer input data isn't showing for some reason. So instead, I'm trying to get the resonance frequency by acceleration ...
user72165's user avatar
3 votes
2 answers
85 views

Maximum of the sum of different sinusoids

How to find the maximum sum of several (more than two) harmonic sinusoidal oscillations of the form $$y_n(t) = A_n\sin(2\pi f_nt+\phi_n)$$ with different amplitudes $A_n$, frequencies $f_n$ and phase ...
Maxim's user avatar
  • 31
0 votes
3 answers
71 views

very basic confusion about the bandwidth of constant signal function

I have a very basic question about bandwidth of constant function $f(t) = K$. As the Fourier transform of a constant pulse is a delta-function centered at zero frequency, the bandwidth (maximum value ...
karavan's user avatar
0 votes
0 answers
24 views

Spectral Theory: A Key to Unlocking Efficient Insights in Network Datasets

In the context of directed or undirected graphs, matrices such as adjacency and Laplacian matrices are commonly used. The eigenbasis of these matrices addresses some practical implications, such as ...
ABB's user avatar
  • 387
2 votes
1 answer
68 views

Frequency components in graph signal processing

As a mathematics researcher, I've delved into the intriguing realm of graph signal processing, yet I often find myself tangled in mental conflicts about certain aspects of this field. Any insights you ...
ABB's user avatar
  • 387
0 votes
0 answers
31 views

DT System with input initially at rest

This is the very basics of Signals but my lecturer has provided barely any notes and I cannot find answers online (not just to this, but most of signals for some reason) Dealing with DT system: y[n]=y[...
Lucy's user avatar
  • 1
2 votes
1 answer
2k views

Why does frequency sweeping double the frequency?

You can generate a signal with frequency f with sin(2*pi*f*t) where t is time. Yet, when I ...
Aravind Voggu's user avatar
0 votes
1 answer
36 views

How to reliably find audio interface recordings in mobile phone recordings

For scientific research, I recorded a few singers with several devices in a recording room. Two of these devices were proper microphones connected to an audiointerface, and they were positioned right ...
user71950's user avatar
0 votes
1 answer
65 views

Why the Discrete time fourier series coefficients of a real discrete time periodic signal are not symmetric about y axis?

If the signal is something like cos(πn/3) , we get the two DTFS coefficients that are symmetric about y axis and the resulting frequency spectrum is an even function . Now take the example given in ...
amoghfyi's user avatar
1 vote
1 answer
30 views

Amplitude Modulation in Scipy Documentation on Hilbert transform

I was reading the documentation on the scipy.signal.hilbert and an example was given there to illustrate the principle. To make it easier to understand, I copied ...
pi_6Squre's user avatar
0 votes
1 answer
84 views

Is the magnitude spectrum of the Discrete Time Fourier Series of a Discrete Time periodic Signal , an even Function?

We know that the magnitude spectrum of a continuous time fourier series representation of a real periodic signal is an even function (i.e. symmetric about y axis). Does this hold true for discrete ...
amoghfyi's user avatar
0 votes
0 answers
21 views

Why is my target showing up with a non-zero centered velocity? I captured this data using the IWR6843A0P using a stationary corner reflector

I need help understanding what I should do to determine why my target is showing up in my Range doppler map with a non-zero centered velocity when I captured my measurement using a stationary corner ...
level2fast's user avatar
0 votes
0 answers
15 views

Real-world examples of unweighted directed graphs

Social Networks, Internet Traffic, Citation Networks, Transportation Networks, and Biological Networks exemplify real-world instances of unweighted directed graphs. Within these domains, the Graph ...
ABB's user avatar
  • 387
2 votes
0 answers
51 views

Baseline correction for XRD data in Origin

I have been trying to process the XRD data for a material, in Origin. I am an undergrad, new to the software, and while I have learnt to perhaps plot the data, I am not able to perform baseline ...
Sevfeynn's user avatar
0 votes
1 answer
153 views

How to find frequency , location and phase of two sinusoid signal buried in noise?

There is a data set which has two different sinusoids buried in noise. Data record has following properties: A data records with a total data length of 2048 points. The sampling frequency is 100 Hz. ...
Thouhidul Islam's user avatar
0 votes
0 answers
39 views

Related to SNR in wireless communication

I am working on a research paper related to wireless communication, wherein I am facing some doubt while writing expression of SNR (which is a ratio of Signal variance in numerator to Noise variance ...
Pranu's user avatar
  • 3
0 votes
0 answers
25 views

Fourier transform processing of iq data

I want to perform fourier transform on the iq data that is taken from spectrum analyzer. The purpose is to estimate phase noise from iq data.
Komal's user avatar
  • 1
0 votes
0 answers
26 views

Program to compare output and input streams to verify volume

I'm trying to wright a program to compare, two sound signals, output (speakers) and input (mic) streams and verify/adjust the volume. I'm using Microsoft Visual Studio C# forms project with the ...
djangocoder5925's user avatar
0 votes
0 answers
29 views

Why are MFCCs of different signals equal?

What I am trying to do: I am trying to extract features based on the difference between a reference signal (white noise in my case, let's call it ref) and different processed versions of it (let's ...
benczejrobert's user avatar
-1 votes
1 answer
81 views

instantaneous frequency for a complex signal

Let $s(t)$ be a complex signal. I would like to know how to find a signal from its instantaneous frequency. I programmed the following function which calculates the instantaneous frequency. ...
bubu's user avatar
  • 3
0 votes
1 answer
22 views

How to reorder the OFDM index before computing IFFT for CFR?

I used Intel 5300 NIC and the CSI tool to get CFR. I also want to apply for a IFFT to get CIR. Do I need to rearrange CFR before I apply ifft? The OFDM subcarrier indexes (for 20MHz) are: ...
evelyn's user avatar
  • 1
0 votes
0 answers
65 views

Correcting Drift and Stepped Pattern in Pressure Sensor Data

I’m observing drift and a stepped pattern in data from a piezoelectric pressure sensor measuring constant atmospheric pressure. the results are the following: The data should ideally be a flat line ...
Optical_flow_lover's user avatar
3 votes
1 answer
93 views

Is $y(t) = y(t-4)+x(t-4)$ time invariant or not?

I want to check the time invariability of this recursively defined function $$y(t) = y(t-4)+x(t-4)$$ We can check time invariability of functions expressed in terms of x(t), but I couldn't find ...
Rohit Joshi's user avatar
0 votes
1 answer
54 views

Frequency doubling of a signal with noise and without

I've been given a task to simulate a real-world scenario, in which a system receives a signal with a carrier frequency of 3.75 MHz. To filter the signal, either a very sharp and resource-intensive ...
Egor's user avatar
  • 1
0 votes
1 answer
86 views

How can a costas loop work when root raised cosine filter used on QPSK signal?

I just finished a costas loop for QPSK signal,I transmit the baseband signal and sent it into the costas loop, which worked well, but when I filter the baseband signal with root raised cosine filter ...
sloth_shelf's user avatar
1 vote
1 answer
81 views

Predicting the "amplitude" of a damped sine wave from FFT

For a sine wave, $A \sin(\omega_0 t)$, with an amplitude $A$, after FFT and calculating the magnitude spectrum we can get a single peak with a height also equal to $A$. This requires proper scaling. ...
AChem's user avatar
  • 569
1 vote
1 answer
50 views

what will be the expression of this shifted cosine signal

My solution is $y(t) = \cos(\omega t) + \frac{1}{2}$ giving it a shift of $\frac{1}{2}$ But I'm a bit skeptic about it, should there be any coefficient of cos to this modification?
Wireshark's user avatar
0 votes
1 answer
90 views

what will be the DC component of this function? [closed]

My answer is that the signal can be splitted into 2 regions, and cancel out the negative and positive areas under the integral, based on the definition Needed some validation on this analysis Thanks.....
Wireshark's user avatar
0 votes
0 answers
48 views

i am stuck on question 3 and isn't getting desired output. can anyone explain what should i do and provide code for this?

Given the autocorrelation function ACF(n)=cos((2/30)n) for n= -5,-4,…0,1,…, 5 use the simplified Lim & Malik iterative algorithm to extend the ACF to 256 points. Note that the simplified version ...
Thouhidul Islam's user avatar
0 votes
0 answers
99 views

Signal plotting on a paper

I needed help in plotting this in a paper, I have 2 signals: x(t) = 4 Tri ((t + T) / 2T) x(t) = sin((2 pi t)/ T).rect((t - 3T) / 2T) I have added my solutions to these signals in the attached image, ...
Wireshark's user avatar
0 votes
0 answers
37 views

Fiber Photometry (Fluorescence) Signal Preprocessing through Source Separation and Baseline Correction

I am working on preprocessing fiber photometry data. The data collection involves inserting fibers into an animal, where the reflection of specific wavelengths of light is captured. We collect two ...
Fazla Rabbi Mashrur's user avatar
0 votes
0 answers
25 views

name for the product of oscillation amplitude and frequency over spectral bandwidth

In the field of signal processing, when a spectral peak is fitted with a Gaussian, is there a name for the quantity obtained by multiplying amplitude with frequency and dividing by the standard ...
fbaroni's user avatar
1 vote
0 answers
31 views

Bearing vibration analysis from audio signal instead of velocimeter measurements

We currently test bearings on a third-party test machine, which uses a velocimeter and reports through a software front end that outputs a low mid and high band spectrum result, and RMS, Peak and ...
DPC's user avatar
  • 11
0 votes
0 answers
35 views

How do i know which operations transformed a signal?

I am doing an undergrad assignment and one of the exercises is as follows: Given the following signal $x(t)$: and another signal $y(t)$ which was transformed from $x(t)$: Describe $y(t)$ in function ...
heresthebuzz's user avatar
1 vote
0 answers
48 views

Calculating phase difference between two vibration signals

The idea behind this question is for misalignment fault we say vibration signals across the misalignment are out of phase. If the signals are just sinusoidal signals with one frequency calculating ...
Genos's user avatar
  • 11
1 vote
2 answers
141 views

What is the best method to filter a signal where baseline and the signal of interest have overlapping frequency range?

I am reading out the movement of a motor arm using a Hall sensor and a magnet pair. The hall sensor measures the distance between the sensor and the magnet. The motor arm is being moved with a band-...
chinmayeelm's user avatar
2 votes
0 answers
125 views

The Discrete Fourier Transform (DFT) decomposes any signal into four orthogonal signal components

Let $F=\frac{1}{\sqrt{n}}(w^{kl})_{k,l=0}^{n-1}$ be the discrete Fourier matrix of size $n$ where $w=\exp^{-\frac{2\pi i}{n}}$. It is a well-known that $F_n^4 = I_n$ where $I_n$ represents the ...
ABB's user avatar
  • 387
0 votes
0 answers
42 views

How to correct for gain and offset errors in a signal?

I have a signal recorded from two different detectors, with different levels of gain. $$ S_{1}(\omega) = \alpha_{1}S(\omega) + \beta_{1} \\ S_{2}(\omega) = \alpha_{2}S(\omega) + \beta_{2} $$ How would ...
Fracton's user avatar
  • 101
-1 votes
0 answers
56 views

Relation between harmonics and quantization [closed]

I'd like to make digital samples that construct sine waves. It's nothing but direct digital synthesis (DDS) before the digital-to-analog converter and filter. I want to make a sinewave sample that ...
chicken's user avatar
  • 19
1 vote
2 answers
80 views

do closer peaks Leak more to each other (spectral leakage in FFT)

I am familiar with the spectral leakage problem in FFT due to a rectangle window for a sin signal giving two peaks that leak to each other. My question is will the leakage to the frequency bins near ...
babzzz's user avatar
  • 11

1
2 3 4 5
46