Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [signal-analysis]

The tag has no usage guidance.

0
votes
0answers
26 views

What is next after a basic signal processing course?

Does anyone know what topics or subjects that I should learn after a basic signal processing? By basic, I mean that we are using the textbook by Oppenheim and Willsky. In the course, we studied the ...
0
votes
0answers
18 views

How to get hilbert marginal spectrum by matlab code? [on hold]

I have a dataset matrix (8000*1) and have to get Marginal spectrum of hilbert . There is a code for this algorithm: https://ch.mathworks.com/matlabcentral/fileexchange/27531-marginal-hilbert-spectrum ...
1
vote
1answer
59 views

Can a Fourier Transform exist even if the j$\omega$ axis is not in the Region of Convergence in it's Laplace Transform

A couple of confusions have been occurred. The Signal I'm considering is f(t) = sin(t)*u(t) Fourier Transform of it can be derived. $-i \pi (\delta (\omega -1)-\delta (\omega +1))$ According to my ...
1
vote
0answers
14 views

How to envelope a non periodic Impulse signal?

I want to analyse a trc oscilloscope file, find impulses and envelope them. In the end I want to plot the envelope. data file (trc): https://ufile.io/z4m4d Code: (Python) ...
-1
votes
1answer
15 views

When does a color channel such as RGB carry more info than a grayscale channel or image?

Typically a gray-scale image gives us more information about an image in terms of a signal processing problem. But when does a color channel carry more info than a gray-scale channel? I understand ...
0
votes
1answer
26 views

EEG Sampling, Which Order should cover my result?

I have EEG data sampling rate is 250 Hz and I want to band pass this data in ( 0.5-3 Hz & 3-8 Hz & 8-13 Hz & 13-30 Hz & 30-40 Hz). Currently, the data is in the frequency range of ...
0
votes
1answer
26 views

What's the point of using Morphological processing concerning images?

I dig deeper in internet to figure out what's the point of morphological processing on images, but i'd rather to hear the answer from people with experience, can you give me a hand with this? Thank ...
0
votes
1answer
34 views

Are resolution increase and noise reduction from oversampling mutually exclusive?

Oversampling a signal means sampling it with a higher sampling frequency than the Nyquist frequency. As far as I know, there are three advantages: Easier design of anti alias filter Increase in ...
0
votes
0answers
44 views

Signal analysis

Need help with signal analysis. I have signal: And now I should to calculate an, bn, Cn with different n (n = 1,2,3...). I know all formulas, but when I tried calculate, I always gets the same Cn. ...
-1
votes
0answers
18 views

How can I select 13 MFCC coefficients?

I have used a build in MFCC algorithm to extract the features from speech signal . According to the MFCC Algo setting, 13 coefficients have to return. Each time i got 13 * n dimension matrix in return ...
0
votes
0answers
14 views

Determine the onset’s in an audio file

I want to determine the onset’s in my audio file which means determine all the frequencies and the corresponding notes present in my audio file. Please help me with an approach in python to achieve ...
0
votes
0answers
30 views

Are there existing algorithms to detect reverb in a voice recording?

I want to be able to detect if a spoken voice recording happened in a room with a lot of reverb or not. I don't need to be able to extract the exact reverb profile of the room. Ideally the algorithm I ...
0
votes
0answers
14 views

inaudible part of signal in MFC transform

MFC transform eventually captures a good portion of the humanly intelligible part of audio signals. I was wondering at which steps of the transform is the inaudible part of the signal rejected? Is it ...
1
vote
1answer
34 views

Spectral averaging without phase information

In the context of signal averaging to reduce uncorrelated noise: Is it possible to perform signal averaging from just the magnitude spectrum of certain signals? Or that would only work if we know ...
0
votes
1answer
17 views

Characterization of the amount of modulation in a signal

We have used the ICRA babble noise to generate an 8-talker babble. As a background - babble noise is used as a substitute for competing talkers as babble noise lacks lexical content, but contains the ...
0
votes
0answers
16 views

Audio signal for each video frame

I have an mp4 video. Is there any way to extract the amplitudes of all the audio signals for each video frame in the available video? That is, suppose there are 1000 audio samples corresponding to ...
0
votes
1answer
61 views

Figuring magnitude and phase response

I've got a linear time-invariant system $$y[n]=\frac{8}{9}y[n-1]+x[n]$$ which I transformed into a transfer function $$Y(z)=\frac{8}{9}Y(z)*z^{-1}+X(z) =>\frac{Y(z)}{X(z)}=\frac{1}{1-\frac{8}{9}*z^{...
0
votes
1answer
39 views

How to determine fundamental frequencies (beats/minute) of heartbeat? (matlab)

read = matfile('ECG.mat'); [cor, lags] = xcorr(read.ecg, read.ecg); read.Fs; So i have read.ecg (signal) and ...
3
votes
1answer
43 views

Compare two signals, find times when they are affected by the same processes

I have two (noisy) signals $S_1(t)$ and $S_2(t)$. They contain information on three distinct events occurring in a physical system. Event $A$ affects only $S_1(t)$, event $B$ affects both $S_1(t)$ and ...
0
votes
1answer
45 views

What is the difference between Spectrogram and Scalogram?

Could someone please explain the difference between the two? Spectrogram: A visual representation of the spectrum of a sound changing through time. Scalogram: (signal processing) A visual ...
0
votes
0answers
21 views

Signal Segmentation

I have a 'theoretically' periodic signal representing measured velocity: In order to average this velocity signal I need to segment my sequence into differents periods like this: The problem is ...
2
votes
1answer
60 views

Denoising a signal using eigendecomposition

I have a complex observable series $Y(t)$ which is the result of summing two complex r.v $X(t)$ (unobservable) and a $\epsilon(t)$ (unobservable). $$Y(t)=X(t)+\epsilon(t)$$ Assume that $X$ and $\...
0
votes
1answer
17 views

How to compute the channel gain from the path loss model of a wireless channel

I did my research but I did not get a satisfying answer. We have a transmitter and a receiver over a wireless communication channel. The channel's path loss is modeled as $ 128 + 37 \log_{10} (d)$, ...
0
votes
1answer
42 views

How to find the coefficients of the following differential equation

An arbitrary signal $v(t)$ pass through the following system, $w'(t) + 5 w(t) = v'''(t) + 320v''(t) + 40 v' (t) + 40v(t)$ How to determine the coefficients of the following differential equation, ...
2
votes
1answer
56 views

Linear Predictive Coding for general signals

I have a signal that's monotonic and roughly linear and have been looking at using Linear Predictive Coding to encode information and compress my signal. I guess my first general question is if this ...
0
votes
0answers
32 views

Calculation expected value of an output signal

I am trying to understand statistical channel functions. I have some doubts. One of them is: let's assume that a channel is characterised by $$h(\tau, t)$$ The output signal is $$y(t)=x(t)*h(\tau, t)...
0
votes
0answers
13 views

How does Praat perform framing of signals?

I am new to Praat and I am trying to find the intensity of a .wav file. When I try to create an intensity object the popup window asks for the minimum pitch and time step. The praat documentation ...
-1
votes
1answer
19 views
0
votes
2answers
41 views

Accurate description of the spectrum of sinusoid waveform added with WGN?

The transmitting signal is $$ s(t) = \sin(20\pi t)+\sin(40\pi t)+\sin(60\pi t) $$ The received signal after AWGN channel is $$ r(t) = s(t)+n(t) $$ where the variance of noise $n(t)$ is $\sigma^2$. ...
1
vote
0answers
37 views

Frequency bins too powerful at the start and at the end of each sample computed DFT data

I've taken the following link http://coding-geek.com/how-shazam-works/#comments as a project to start practising and learning signal processing and python programming for me to get started in speech ...
4
votes
3answers
242 views

Is Linear Prediction ever exact?

I'm just learning about linear prediction and was wondering whether or not there are any signals that would produce no error if run through a linear prediction algorithm. I was thinking (maybe naively)...
2
votes
0answers
26 views

FFT Service on AWS? [closed]

Hopefully this is the right forum to post this question. Initially posted to Meta. My mistake. Learned the hard way via downvoting. I searched AWS and Microsoft cognitive services for an FFT web ...
1
vote
1answer
33 views

make a voice sound signal play faster

Suppose $x(t)$ is a signal containing a voice. How can one derive a signal playing the same voice faster. I tried $x(t+\lfloor{100t\rfloor}/100)$ to double the speed; But it adds a buzz sound. Is ...
1
vote
1answer
49 views

GPS Coarse Acquisition PRN Codes

Are the actual 1023 bit sequences for each of the 32 GPS satellites available to consumers? I found the IS GPS 200 but it doesn't list the entire sequences. Are verified sequences available for ...
1
vote
0answers
42 views

How to estimate noise by eigendecomposition of the variance covariance matrix?

I'm new here so I will try to be as clear as possible. I am trying to apply some techniques from signal processing framework to denoise financial time series. I would like to know if what I am ...
1
vote
1answer
310 views

Practical book in C [duplicate]

Is there any practical “go to” book that demonstrates the main dsp methods for time series written in C for practical applications? (Doesn’t have to be for hardware, but for any raw data such as ...
-2
votes
1answer
45 views

Signal reconstruction from sampled signal? [closed]

Can we construct exact analog signal at receiver as same as the source from the sampled signal?
0
votes
1answer
31 views

Implementing real-time signal processing filters

I’m currently working on my capstone for school, and I’m looking for some guidance/tips when it comes to real-time filtering. The nature of the project is to monitor breathing patterns, send the ...
0
votes
1answer
40 views

Signals and Systems - LTI - Transforms - Impulse Response

I have $x(t)-> LTI -> y(t)$ where $LTI=h(t),H(jw)$. and $H(jw)=ab/((a+jw)(b+jw))$ where a and B are real numbers. I am wanting to find the impulse response $h(t)$ as well as the input/...
0
votes
1answer
31 views

Find identical audio signal

I have a long audio file (in wav) and a short audio file (in wav) that has been copied from the long file. Now I need to find the correct location where the short signal has been copied from. I tried ...
-2
votes
1answer
32 views

Frequency component not filtered properly

Are frequency components other than wanted signal present in the output? If yes then why does it not disturb the original signal? I think all practical filter responses are not ideal, so all frequency ...
0
votes
1answer
27 views

Real and Imaginary data from Network Analyzer

I’m having a hard time grasping what exactly ARE the real and imaginary numbers in my s-parameter data. Most of the time I just set the NA up in logmag/phase to find the loss though, say, a filter or ...
0
votes
0answers
38 views

Stability in evaluating real part of a Fourier transform

I posted this on maths stack exchange but realised it might be more appropriate here. So forgive the cross posting! I have a signal $S$ and want to evaluate the magnitude of the real part of it as ...
0
votes
0answers
23 views

Estimating velocity using MEMS sensor (accelerometer part)

I wanted to know how I can estimate velocity of a particle (contained with a sensor) from the acceleration output of a MEMS sensor device in order to find the total kinetic energy of the particle? ...
1
vote
1answer
67 views

Finding audio “tics” in stereo wav files using python

I have thousands of audio files that I want to "batch" process searching for audio tics. This is easily done using a DAW but that requires opening each file independently, searching for the tic (...
0
votes
1answer
29 views

Equalization : using the spectral or the temporal signal?

I'm trying to equalize a sound signal - using a JAVA program - and I'm using this process : 1/ Conversion of the temporal signal to a spectral signal, using a FFT 2/ Applying a coefficient to each ...
1
vote
1answer
62 views

Damped sinusoidal form FFT of signal

I'm doing an assignment for the course Signal analysis where I have to analyse a signal. I've tried quite some things now but it's still bothering me that the FFT is looking weird, and not looks like ...
1
vote
1answer
32 views

Ways to parallelize Sifting in EMD (Empirical Mode Decomposition)

Sifting process, which is recursive in nature, is used in EMD (Empirical Mode Decomposition) to decompose the signal (x(t)) into Intrinsic Mode Functions (IMFs) and residue, which is a monotonic ...
1
vote
0answers
21 views

What is the signal-noise model of laser induced fluorescence?

The following image is an example of a fluorescence signal trace from the photomultiplier tube detector (PMT). Each spike represents one fluorescently labeled cell. This signal model is definitely ...
0
votes
1answer
61 views

What's the difference between SISO and SIMO in using matched Filters

Suppose we are transmitting a signal $x$ in $OFDM$ with $N$ subcarriers, After performing Parallel/Serial conversion and then N-points FFT, we suppose to have signal $s = IFFT^Hx$, Then adding the ...