Questions tagged [array-signal-processing]
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42
questions
0
votes
0answers
20 views
Transforming large size kernel (filter) into equivalent small size kernels(filters)
I have a problem where I want to convert kernel of large size, i.e., 64x64, into the number of 3x3 size kernels that convolving them with the same input image results in the equivalent output. (It ...
0
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0answers
21 views
What is Ad-hoc microphone array?
I have stumbled upon this term in many papers, though no one bothers to elaborate. Is this the case where I do not have prior knowledge of the array structure? or otherwise is it the number of ...
0
votes
1answer
54 views
Discrete Signal Windowing
How do we apply windowing of 50% (4 samples) to a discrete signal with the odd number of values as 1234567?
Is it done as: ...
0
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0answers
14 views
Calculation of the clutter component of the space-time snapshot
I've encountered a silly problem during the implementation of SMI beamformer. I have KASSPER project datacube from IEEE dataport as my data and I want to calculate covariance matrix from that datacube....
1
vote
1answer
68 views
MUltiple SIgnal Classification (MUSIC) Implementation
I have a linear 4 element antenna array currently in my design, I am able to obtain the I/Q data from each antenna. Now I am trying to implement the MUSIC algorithm to obtain the AoA (Angle of Arrival)...
0
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0answers
15 views
When does the narrowband model in array processing fail?
I am not sure that I understand well the narrowband assumption in array processing. I wonder how it simplifies the model and what would change if not assumed. Also, what will happen if I apply the ...
0
votes
0answers
24 views
Calculate the percentage of accuracy with which user made the assigned sound
I want to design a web-app for my cousin who is 2 years of age in which i have implemented a functionality in which when an image is clicked some sound gets played and the user has to make the same ...
0
votes
1answer
41 views
Zero peaks in fft data even after subtracting mean
I have a time series sensor data. It is for a period of 24 hours sampled every minute (so in total 1440 data points per day). I did a fft on this to see what are the dominant frequencies. But what I ...
0
votes
1answer
297 views
Python code for QPSK modulator [closed]
Have any of you done anything like QPSK Modulation in python? I am in the middle of it and having problems in setting up bits? like odd and even bits.
Have you got any idea?
Regards,
Sam
0
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1answer
91 views
Question about eigendecomposition, signal subspace and their properties
Lately, I am readig a paper titled
A Subspace Method for Estimating Sensor Gains and Phases.
In it, it is mentioned:
There are $m$ sensors in the array, $n$ known narrowband far-field signals($m \...
0
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0answers
18 views
How to get spectrogram of an array in MATLAB
So.. I want to make spectrogram out of 4 signals that i need to add in array.
When I add them in array, it looks like this s=[x1 x2 x3 x4] or with values: ...
2
votes
1answer
81 views
Source Localization with the BLUE Estimator
I'm trying to implement BLUE estimator in MATLAB for source localization and after my research I've come up with a theoretical example in Steven Kay's "Fundamentals of Statistical Signal Processing: ...
0
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0answers
24 views
Calculate SINR and Array-Gain for acoustic Beamforming in Matlab
I'm struggling to understand the equation and the reasons for this equation from Matlab's acoustic beamforming example. Here is the link:
https://se.mathworks.com/help/phased/examples/acoustic-...
0
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0answers
17 views
How to examine intrinsic mode functions?
After decomposing a non-stationary signal using empirical mode decomposition, how can I examine extracted intrinsic mode functions to be mono-component?
0
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0answers
18 views
Visualization of wavelets coefficients using python
I need to prepare a plot similar to figure below using coefficients of details of a wavelet transform.I am trying for more than 2 weeks to find how I can do it.
This plot represents coefficients of ...
1
vote
0answers
43 views
Sign of manifold vectors in monostatic phased-array radar
I am reading some notes where the impulse response of phased-array to is given by;
$$
\beta S(\theta, \phi) \bar{S}^H(\theta, \phi) \cdot \delta(t-\tau)
$$
where
\begin{align}
\bar{S}(\theta, \phi)...
0
votes
1answer
60 views
Detect when signal starts oscillating
I have a signal which consists of oscillations riding on square waves as shown in the image below. I wish to detect the time at which oscillatory events occur (as shown by the red star).
Each square ...
0
votes
0answers
51 views
Negative instantaneous frequency in Hilbert Huang transform
How can I get rid of negative instantaneous frequencies (IF) of Hilbert Huang transform. Negative IF is physically meaningless, so why they are always exist?
How they should be interpreted?
I use ...
0
votes
1answer
61 views
How do I create a polar plot from a multi-channel sound file?
I have a multi-channel sound file from a microphone array. I want to get the polar plot in Matlab in order to get the directivity patter of the sound source. How do I do this? I did the FFT on the ...
0
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0answers
26 views
Channel selection for Source Separation
I have a two mic source separation algorithm which gives two outputs/channels. How to select speech dominant output from the two output signals?
3
votes
1answer
226 views
Radar signal processing flow chart
I'm new to Radar in general, and I'm studying RADAR using online resources. I came across the following slide which shows the process flow of the Radar signal processing.
The thing I don't get in ...
3
votes
0answers
58 views
How to compare imaginary coherence values?
High, I am currently writing my Master's thesis on susceptibility for hypnosis. I am comparing EGG signals of lowly and highly susceptible individuals.
The imaginary coherence is given by:
$$ \...
0
votes
0answers
25 views
Temporally synchronize two different or more real time digital audio signals
Are there any DSP techniques to temporally synchronize two different or more real-time digital audio signals without timestamp information?
0
votes
1answer
25 views
Arbitrary shaped RIR generator
I wish to simulate some sound sources convolved with a Room Impulse Response (RIR) and impinging on a spherical microphone array. I could find a couple of generators online (such as this one), though ...
-1
votes
1answer
58 views
Is it possible to estimate the DOA from real samples only?
I'm sampling a ULA with a scope after transmitting a CW.
I'm wondering if I can estimate the DOA assuming I'm interested only
in the range [0,90] [deg] and not the full [-90,90] [deg].
The first issue ...
0
votes
1answer
43 views
The frequency-domain spectrum obtained using MATLAB's FFT function seems inaccurate
I am using MATLAB R2018b on a Windows 10 PC. In order to obtain the frequency domain information of a signal, I'm applying MATLAB's FFT function. The signal of interest is obtained from an experiment ...
1
vote
2answers
107 views
Number of microphone limitation for Spherical Harmonics based DOA estimation
I am following this book "Theory and Applications of Spherical Microphone Array Processing", as well as this paper on DOA estimation "Eigenbeam-ESPRIT for DOA-Vector Estimation".
My dataset is ...
0
votes
0answers
23 views
DOA estimation of moving, radiating source in the near-field with nonuniform Doppler shifting
I am trying to estimate the DOA of a radiating source using two passive sensors.
In the case of a stationary source, I find the lag $k$ of the maximum in the sample cross-covariance sequence $E \...
0
votes
0answers
44 views
How to crop a song and mantain the same values in the sample vector?
Does anyone know how can I crop an audio signal and maintain the same values in the sample vector?
I am working on a audio signal processing project for song recognition in Python and I wanted to ...
1
vote
0answers
29 views
Blind source separation from microphone array
I was following this article and I wanted to "borrow" their Idea for my own work.
The difference is that I am using a microphone tetrahedral array and not a binaural microphone. I have two different ...
0
votes
2answers
70 views
Convolution property
Is the convolution of two equal signals the same signal?
I have this system:
and i have to find $h_1[n]$ (which i've been struggling for a while), given
$$ h_2[n] = u[n] - u[n-2] $$
and $h[n] = ...
5
votes
5answers
1k views
Multi-channel audio upsampling interpolation
I have a four-channel audio signal from a microphone tetrahedral array. I wish to upsample it from 48 kHz to 240 kHz.
Is there a preferred interpolation method for audio? Does cubic ...
3
votes
2answers
236 views
Tetrahedral microphone array beamforming
I have a microphone array of 4 channels taken as channels [6,10,22,26] from Eigenmike spherical microphone array. I wish to do 3D beamforming and create $8\times 4$ beams, 4-elevations with 8 ...
0
votes
2answers
310 views
Delay in Savitzky-Golay filtering
I am applying a Savitzky-Golay filter to a signal, using the scipy function.
I need to calculate the lag of the filtered signal, and how much is it behind the original signal.
Could someone shed ...
1
vote
1answer
88 views
By using array antenna and a MUSIC algorithm, how many targets could be detected?
By using an array antenna which has N receivers, How many targets could be detected and classified when we use the MUSIC(MUltiple SIgnal Classification) algorithm?
1
vote
1answer
28 views
Feature normalization (scaling) for Hyperspectral images
have been straggling with the concept of feature normalization for the hyperspectral images. Respect to my problem I have attached a picture of my problem which clearly stands the issue which I have.
1
vote
0answers
38 views
Excluding points too close to a set of coordinates
I was wondering if anyone can help me. My ultimate aim is to take an image like the one shown and draw line between the white and black blobs that show a direction and output the coordinates in the ...
1
vote
1answer
113 views
Separating two frequency component
How can we separate two frequency component when they get mixed means when signal get mixed with noise how receiver can judge which part is signal and which is noise ?
0
votes
1answer
33 views
How to make sinewives with array input, for-loop functions and operate array with others [matlab]? [closed]
Thanks to previous question, I got some clues to resolve this one.
But, I still get some problems here.
...
1
vote
0answers
331 views
Time-Delay beamforming delay computation
I'm trying to implement a beamforming algorithm in python and I'm stuck with the time-delay computation for a rectangular array.
I'm using the following equation to compute the delays based on the ...
-1
votes
1answer
165 views
Calculation of Correlation Matrix
In the description of any Beamforming Technique for microphone array signal processing there is a usage of the co-relation matrix.
What is the use of calculating such a co-relation matrix in such ...
9
votes
3answers
417 views
Practical wideband digital beamforming for large arrays in radar applications
I do understand the mathematics behind digital beamforming but I am not sure how such systems are practically implemented. For example, in a typical wideband FMCW radar operating in S-band, the (...
