Questions tagged [signal-analysis]

The tag has no usage guidance.

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

Maximum Value of DSNR in Detection of Signals in Noise Second Edition

I am interested in problem 8.5 of Detection of Signals in Noise, Second Edition. The problem calls for finding the maximum value of DSNR. I have done so, but my solution does not agree with the ...
0
votes
1answer
118 views

application of wavelet to vibration signal

I ask you to help me to interpret this figure corresponding to a diagnosis of gear failure using CWT (Haar); I have already worked on the analysis of the vibratory signals using the FFT; But since the ...
0
votes
1answer
134 views

Distinguish between sinusoidal oscillations and rythmic pulses

I want to distinguish between a sinusoidal oscillations and rythmic pulses. Which method can i use to do that? I want to implement a detector that can distinguish between this two types of signals. ...
0
votes
1answer
91 views

GPS Code Phase usage

During Cross-correlation process: xcorr=ifft(fft(a)fft(b)∗) we have frequency offset and code phase offset. How is it used later in the process of finding a ...
4
votes
1answer
179 views

Overlapping power-of-cosine windows with constant weight

I would like to refer you to a relevant question I posed on the Math StackExchange: A generalisation of the Pythagorean trigonometric identity. As can be seen from the question and the answer, what ...
0
votes
1answer
53 views

Measure 3-D length using smart-phone's accelerometer

I'm wondering if we can measure 3-D length only by our smart-phone's accelerometer. And we all know these low cost IMUs are not accurate. You can model accelerometer's error this way: $$ a = f*a' + g ...
2
votes
1answer
101 views

Separating/recovering base signal from two mixed signals, given phase information

I have collected two signals, $B_1(x)$ and $B_2(x)$. The signals start and end at the same $x$-values. Each signal $B_i(x)$ contains: a base signal $b(x)$, which is the same for both, and a signal, ...
2
votes
1answer
530 views

MFCC Classification

I'm working on gender estimation from speech signal and I completed MFCC feature extraction. So now I'm trying to estimate gender from these features. But I have frames for an audio file and I ...
1
vote
1answer
66 views

Finding the Sections of Signals that are the Most Similar

I have two discrete signals, $A$ and $B$ (both with $L$ values). I want to look for the section (of a certain length $R$) on each signal ($[A_1:A_1+R]$ and $[B_1:B_1+R]$) where they are the most ...
0
votes
1answer
35 views

Different number of modes while performing the EEMD (Ensembled Empirical Mode Decomposition)

I am performing an Ensemble Empirical Mode Decomposition (EEMD). I wrote a MATLAB routine to perform the EMD. I noticed that when adding white Gaussian noise to the input signal, sometimes I obtain a ...
-1
votes
1answer
46 views

How to determine the shape along which an object is moving [closed]

The object moves as it pleases and receives its GPS coordinates. How to determine which shape the object is moving along? For example, we accumulated 10 points, processed them and produced the result: ...
0
votes
0answers
24 views

Remove noise from VGA image

I have 2 color images generated from same X-ray machines, but one of the image is obtained using VGA cable. Therefore the RGB intensities differ in the 2 images. I am using Object detection to detect ...
0
votes
1answer
46 views

Frequency Domain Distribution

I have a complex signal in the time domain normally distributed. What will be its distribution in the frequency domain? I assumed since the frequency domain is a linear transformation the distribution ...
4
votes
1answer
269 views

Phase Modulation and Intermodulation Anomaly ? (Spectrum plots inside - **Updated**)

I have a MATLAB script for modelling a two tone signal (a sum of two sinusoids) going through a non linear transfer function (such as an amplifier). The amplitude of a signal is amplified non linearly,...
0
votes
0answers
34 views

Reconstructing a signal from multiple filtered copies using overlapping tapered windows

I have an audio signal that I need to process and analyse in blocks. I've now decided to process it using overlapping non-symetric Hanning windows of length M = 9600 and a hopsize of R= M/2. I zero ...
8
votes
5answers
4k views

Why complex numbers are represents as a+ib and can't be as (a,b)?

I am confused as why do we need to represent the complex numbers with the imaginary y-axis if we can simply represent them as (x,y) ? I've read that Multiplication by i is an anti-clockwise rotation ...
1
vote
1answer
90 views

Audio from multiple microphones mixed to mono and ASR

I am trying to do speech recognition on an audio file which has 1 channel (mono). My problem is that the channel is comprised of the signal of 3 microphones which have captured the audio at different ...
0
votes
0answers
22 views

Legacy LongRange Mode information (mode 1 in the my attached link)

Mode 1- Legacy Long Range Packet Format and Im attaching a photo of ti reference: link for more information about this mode category : TI SWRA642 I want to understand the packet format, what's my ...
1
vote
2answers
142 views

Augmentation for EEG signal classification using Deep Learning

Augmentation is a technique that we use in deep learning for expanding the training dataset. It includes different ways of modifying an image and adding it to the training dataset. My question is if ...
2
votes
1answer
341 views

How to make sense of audio file's $\textrm{dBFS}$?

I'm trying to build a song visualizer using the FFT method. When I analyze the audio, I get the $\textrm{dBFS}$ value for each frequency range. From my understanding, $\textrm{dBFS}$ is in the range ...
0
votes
1answer
122 views

How to apply baseline methods to MNE preprocessed raw EEG signals?

I am new at EEG preprocessing and classification. I have followed Clemens Brunner's blog https://cbrnr.github.io/2018/01/29/removing-eog-ica/ as a tutorial for MNE. This is how I have preprocessed ...
0
votes
1answer
32 views

Calculating SNR of a complex-valued signal correctly

I have an array of complex-valued data. I would like to modify the array by injecting an artificial signal at a chosen Signal to Noise ratio. I have seen the signal to noise ratio for complex-valued ...
1
vote
0answers
50 views

Respiration (breathing) signal movement artifact removal

Situation: I have breathing data of participants who have done different things during the study which caused their breathing change; watching mindless video to which resulted in unconscious regular ...
0
votes
1answer
36 views

What is the actual format of this audio file?

I am collecting some data from jotform .wav widget. All the audio files are in .wav format. But when I tried to open the file using python ...
2
votes
3answers
146 views

Signals - question due to sampling

I don't have an idea how to start it. Help pls :) $$m = z(t) + \frac{\operatorname{Sa}(t-T)}{4}$$ We have some signal $z(t)=\left(\operatorname{Sa}(\frac{t}{T})\right)^2$. How often the m signal ...
0
votes
0answers
16 views

MPEG Audio Constant bit rate conversion

I am trying to convert few .wav files to .mp3 format The desired .mp3 format is : I tried with FFmpeg with this code : ...
0
votes
0answers
25 views

How to measure EVM?

I am trying to understand the concept of EVM and how it is measured at different points in transceiver. I have a basic understanding that the error difference is calculated between two vectors (i.e. ...
2
votes
2answers
146 views

Autocorrelation and Spectrum Density

Wiener–Khinchin theorem states that autocorrelation function and power spectral density are a Fourier-transform pair - see Wikipidia (and lots of other resources). That means autocorrelation should be ...
0
votes
1answer
223 views

How to detect the maximum resolvable spatial frequency of camera?

I am trying to calculate the minimum line pixel width that can be distinguished from noise as shown in the camera test chart in Figure 1 where the thinner lines on the left are getting more and more ...
0
votes
0answers
32 views

How to implement Walsh demodulation in matlab?

1 1 1 1 ==> 0 1 -1 1 -1 ==> 1 1 1 -1 -1 1 -1 -1 1 I have this sequence of walsh spreading ...
0
votes
1answer
28 views

Having Problem about DownConversion

I hope, you are doing well. I want to ask question about baseband conversion. Background: I generated two AM signals in MATLAB, which one of them is shifted in time. I multiply the signals with $\cos(...
0
votes
1answer
57 views

How to calculate variance of noise on a noisy image (Noise+Signal)

I have a long exposure image captured at 70ms. (I1) (As attached) I also have another image captured at 0.7ms with Gain24. (I2) (As attached) This image has both noise and signal together. I would ...
0
votes
1answer
59 views

How to make signal smooth using filter?

I have measured the output of a mechanical system and obtained the signal shown at the attached image. I want to make it smoother by removing the chattering (I think it is called chattering). In order ...
0
votes
1answer
39 views

How to check my CRC of my RF packet? [duplicate]

The "problem" is that I want to validate if my received RF packet is valid or not valid, in other words I want to validate if my RF packet corrupted or not corrupted . the transmitter that ...
1
vote
2answers
70 views

Output of marginally stable systems

In' b.p lathi's book of systems and signal it is written that "marginally stable systems have one important application in the oscillator, which is a system that generates a signal on its own ...
1
vote
2answers
209 views

Significance of sequency ordering in Walsh-Hadamard matrices

So I've been doing some reading into Hadamard and related matrices (Slant, Walsh, , and have observed that there are three typical "orderings" of the rows based on various criterion. E.g. "Natural", "...
0
votes
1answer
61 views

Similarity or Relation between Walsh Hadamard Transform and Slant Transform

Is there any relation between Walsh Hadamard Transform and Slant Transform? Or is there any common property or similarity?
0
votes
1answer
85 views

About the variance of the coefficient of narrowband noise when using signal-space representation

Assume that n(t) is a white Gaussian noise process with zero-mean and power spectrum density $N_0/2$. By using the signal-space representation, it can be expressed as: $$n(t) =\sum_{j=1}^N n_j \phi_j(...
4
votes
1answer
133 views

A-weighted Digital Filter for 1/3rd Octave Band Analysis

I want to do a 1/3rd Octave band analysis on a noise signal. But the sound pressure levels should be in dB(A), i.e., and it should be A-weighted. For this, I am using the A-weight function from this ...
0
votes
0answers
18 views

How NLMS/LMS adaptive filter used for noise reduction acts on input signal with low frequencies(DC offset/baseline wander)?

I am using Matlab to implement a real-time adaptive filter of length 4 for noise cancellation using the NLMS method/ I also tried the LMS method. My aim is to denoise biomedical signals, and for the ...
0
votes
1answer
24 views

How to determine a suitable threshold when using amplitude thresholding method for spike detection?

I have seen number of approaches that have been introduced in the literature for spike detection including, amplitude thresholding method, Nonlinear Energy Operator method, and template matching ...
0
votes
1answer
29 views

simulation of lin-log amplification

I struggle with two simple questions. First. What is the distribution of the signal on the output of the lin-log amplifier if Rayleigh noise is driven to the input of it. Using an approach with ...
1
vote
0answers
29 views

Spatial frequency and video frequency of an image

in my lecture notes about image sensors (CCD, precisely) I have read the following statement: The transfer function $F(\omega)$ of the image sensor is related to its spatial resolution function $F(\...
0
votes
0answers
27 views

Extracting rms delay, delay spread, and CIR from power delay profile

I have a spread spectrum channel sounder running the following transmitter and receiver: When running it over the air (~2km), I get the plot of the correlator output: I can see that there are peaks ...
0
votes
2answers
263 views

Threshold for peak detection of noisy signal in frequency domain

I have a noisy signal (Gaussian Noise) with a known SNR and known Noise variance. This signal contains a number of Frequency components. My ultimate objective is to detect the components of the signal....
0
votes
2answers
44 views

Sine Dipole formation using two hydrophones

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 ...
0
votes
2answers
481 views

Why does the addition of noise improve coherence between two signals?

Taking a simple example of the coherence between two signals, each composed of two sinusoids of frequency 100 and 200 Hz, I expect the coherence to show two peaks in the spectrum located at precisely ...
1
vote
1answer
31 views

Power Spectrum analysis arbitrary length signals

I have signals belonging to diseased and healthy samples recorded from multiple electrodes. These signals are taken monthly and are of arbitrary length (say 4-5 mins). I am planning to do a power ...
0
votes
2answers
69 views

Can an audio recording tell whether it is made in a large or small room?

The conversation of one or more people will be analyzed. I think need to look for something similar to reverberation or echo in an audio signal. How can this be implemented? Update: small room is ...
4
votes
4answers
12k views

Simple and efficient algorithm to detect frequency and phase of a sine signal

I need an algorithm to detect frequency and phase of a pure sine signal. The frequency of the input signal changes between 0 and 100 Hz. The value of the signal gets captured with a frequency of 20 ...

1
2 3 4 5
33