Questions tagged [python]
Python is a high-level interpreted general programming language. Python has popular numerical and scientific libraries/packages, most notably numpy and scipy. The scipy.signal package is a powerful signal processing software collection. This tag covers the use of numpy, scipy, and other Python packages often used for SP computations.
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Help with Implementation of Communication System and Understanding Frequency Response in Python
Professor gave us task to implement communication system as in picture
Communication system is made for the transmission of 32 frequency-multiplexed analog signals through a communication channel. ...
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Looking for paper about applications of using phase screen to model space laser communication
A phase screen is a concept used in wave optics to model the statistical properties of wavefront aberrations caused by a medium. In the context of light propagation through atmospheric turbulence, for ...
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Testing CNN model using sound generated from pyroomacoustics room simulation
I have generated a large set of audio using Pyroomacoustics for room simulation, employing a circular microphone array and a single sound source.
I have successfully trained and tested a CRNN (...
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Plot an eye diagram with a cmap 'hot'
I'd like to plot an eye diagram with a 'hot' colormap that becomes clearer not when the signal has high values, but when the signal is dense at an instant in time, see picture below.
Here is what I'...
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How to get Power Spectral Density of file using this research paper method?
I came across this research paper. In this they have mentioned power spectral density calculation of various file. I have read the paper and try to calculate and plot the graph, don't know it correct ...
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How to calculate a 3D Fourier Transform?
I am currently employing a centered finite difference method to simulate the excitation of a circular membrane by a forcing term in Python, and the code is functioning as intended. To further enhance ...
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How to play sound at specific location (horizontal/azimuth) using wav and python ? without libraries
how to set sound location left/right (in mono audio) and azimuth (up/down) of the wave? I know there are a lot of different libraries doing that, but I'm interested in some minimal examples to ...
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Python - CV, contour and measurements
I have small problem with cv in Python and rhombus. I can read frame from the camera and create contours...
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Face Detection real-time with Local Binary Pattern
I'm writing for code to detect human face by Local Binary Pattern algorithm in webcam, but with my limited knowledge in optimization code, I having to struggle in detect in each frame , I want to say ...
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Sound having lower rms values but higher loudness.What are the possible reasons?
I have some noise datas which are having lower RMS values. But don't know why they are very loud when I am normalizing and playing them. After normalizing the audio remain still low rms values. But ...
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FIR Filter Design in python
This is mine code for fir_filter_design in python. But I'm getting wrong output for low-pass, band-pass, and high-pass magnitude response.
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Problem by designing and filtering a Bessel-Thomson filter in Python
I have an issue when I want to filter a signal with a 4th order Bessel-Thomson filter with a cutoff frequency at 18 GHz.
1. Generate data at 50 Gbps (T-spaced)
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Local Binary Pattern rotation
How does LBP work? To learn that, I decided to calculate by hand for the matrix but the problem is about the rotation pixel over the image based on the radius and neighbor of LBP. I do it clockwise ...
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Get FFT from a Wav after a hanning filter with 25% overlap?
I have a program that allows me to record wav and get the FFT all at the same time.
However, the FFT I have I can't export it to work with. So I need to make a script to get it from the wav.
Can ...
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what is the meaning of the second line in the code?
what is the meaning of the second line in the code , i am not understanding the meaning of it
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Frequency spectrum of interpolated sine
When interpolating a sine wave in Python, it seems I get a lot of additional frequencies closely around the fundamental. Why is that the case? I would have expected a more or less similar spectrum, ...
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Time-varying shot noise generation
I'd like to model the behavior of photodiodes, the input is like data bits (0 & 1) where each bit is represented maybe with 100 samples / bit and the bit rate is $B$ bits/sec with period $T_{bit}=\...
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How to adjust the length of the window of the Fourier transform with respect to the length of the signal in Python
I ran the following code in Python, setting the window length to 5s, but he reports an error as the window length does not match the signal length. How should I adjust it please?
code:
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Simulate Op-Amp low-pass transfer function in Python
I am struggling to simulate the frequency response of a simple op-amp low-pass transfer function in Python. The results I get are not accurate. The transfer function is $H(s)=\frac{1}{1 + s\tau}$, ...
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Detecting the piano notes using python
I am trying to build a small application that is very similar to simply piano, where I am trying to detect the piano notes, my program will be listening and when a key gets pressed it will estimate ...
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PyWavelets CWT : error when differentiating after convolution?
I'm trying to understand the implementation of CWT in PYWT. This topic has already helped me quite a lot but there is still a thing that is unclear to me : why is the result differentiated only after ...
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How to reconstruct MMW image using electrical field in each direction at Receiver points using Back projection algorithm
I have used a structure including 109 Receivers and 4 transmitters in order to do MMW imaging(multistatic imaging). Imaging was done in 3 different frequencies. So, now I have electrical field in each ...
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Given two low-pass digital IIR filters, find bandpass coefficients
In the case of FIR filters it is easy to get a band-pass filter by subtracting the coefficients of two low-pass filter filters or by convolving a high-pass and a low-pass filter:
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I have a distorted signal and want to achieve a perfect wave in the output. What am I doing wrong?
I've been told to use a digital filter, but this solution achieves what I've been told to do.
It is so simple it is dumb, what am I missing here? I want to be more scientific about it.
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Implementing logarithmic AGC (automatic gain control)
I'd like to implement the Log(arithmic) AGC from
Understanding Digital Signal Processing
But with
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Unexpected frequency components after applying bandpass filter in python
When I apply a bandpass filter in python to a pure sinusoidal signal, it seems that after filtering I get different frequency components across the spectrum (see orange line below). It looks like ...
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Help with Implementation of Transfer Function using Python or MATLAB
Relatively new to the DSP side and wanted some help to implement this approach using Python (with NumPy, SciPy libraries) or via MATLAB.
Background of the problem:
I'm running a linear dynamic loads ...
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What is the best method of describing the effects of downsampling on a chromatographic signal?
I am in the process of compressing a set of chromatograms to develop a preprocessing pipeline, that will end with DTW for peak alignment. During this process I have downsampled a signal from 0.4 ...
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Incorrect epoch labelling
I am processing an EEG signal acquired by showing 10 image of each of 40 classes. I want to label the signals converted to epochs to their corresponding class labels.
The ...
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Overall spectrum computation from Short-Time-Fourier-Transform
I am trying to computing the overall spectrum of a given signal from its Short-Time-Fourier-Transform. I am using python to do this and I wrote my function to compute the STFT:
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Is lock-in amplifier a correct approach?
I have a noisy signal which is the voltage output from a photodetector circuit. I have researched about extracting signals, and found that lock-in amplifiers are one of the main approaches for the ...
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Lock-in Amplifier: How to improve the output of lock in amplifier?
I tried to extract a pure signal from the noisy signal using a lock-in amplifier with the help of python code.
The output is from a photodetector circuit.
These are the reference signal, expected ...
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Periodicity problem with FFT for generating "starburst" from aperture
I am following a paper on computationally modeling optical phenomena within a lens. (https://resources.mpi-inf.mpg.de/lensflareRendering/)
At some point they use the Fourier power spectrum of an ...
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Removing Phase shift in ECG signal
I have ECG signal sampled at 100Hz & using Python to remove noise, and generate a template signal from the collection of ECG from a total of almost 4700 signals. I have removed the noise from ECG ...
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Transfer Function Estimate
This is related to this post: https://engineering.stackexchange.com/questions/56050/obtaining-the-open-loop-gain-estiamte-the-gain-and-phase-frequency-response
Using python, I would like to write a ...
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Python - Discrete deconvolution using Toeplitz matrix
Lets say I have 2 vectors (1D signals that are sigmoids): $s$ and $m$, both related through the relation: $m = s * r$, my goal here is to recover the vector $r$ (should be a gaussian $\rightarrow$ ...
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Abnormal Y-axis value after performing FFT
I have an UFF file which consists of Vibration data. The objective is to convert the timewaveform signal to frequency domain.
I have written a python script to convert the timewave form signal to ...
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Audacity vs MATLAB/pyhton for basic signal processing concepts? [duplicate]
Use of "Audacity"for teaching undergraduate labs of digital signal processing for electrical engineering students?
My above realted linked question has got some good answers.
Traditionally ...
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Deconvolution using Toeplitz matrices [duplicate]
Lets say I have 2 vectors (1D signals that are sigmoids): $s$ and $m$, both related through the relation: $m = s * r$, my goal here is to recover the vector $r$ (should look like a gaussian).
I tried ...
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How can I apply a phase shift to an LFM pulse?
I am modelling radar scenarios in python and am trying to make a model which retains phase information. To do so, I'm envisioning something which works like this:
Generate samples of an LFM waveform ...
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Can I apply an hilbert transform on a signal in subsegments [windowed hilbert transform?] [duplicate]
Consider I have a signal x which has N samples, N being a very large number.
Could I create y, the analytical signal of x, by ...
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Calculating average peak-to-peak amplitude in a fft plot
I have the following code to calculate and plot fft. The data consists of voltage, current etc. sampled at 30 samples/sec.
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How to plot a sawtooth chirp waveform using an array of frequency and time for an FMCW radar?
Before switching to use sawtooth I was using sine wave but in sine wave high frequency content was not clearly visible, But I don't have any experience with using sawtooth waveforms. I am going to ...
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Convolution and Fourier transform for 1D signals
My problem is the following, I have 3 curves/signals (1D) , the measure, the signal and the resolution of my detector: $\mathcal{M},\mathcal{S},\mathcal{R}$, knowing that : \begin{equation}\label{eq:...
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How to construct a bandpass filter with minimal loss in amplitude/power near the lower and upper frequency limit in Python?
I am analyzing functional MRI data with a sampling rate of 1 second (1 Hz). The frequency band that I am interested in is 0.01-0.2 Hz.
Regarding measurements, I am interested in computing (1) the ...
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Robust method to detect pinpricks in an image?
I expose films in a jig with pin pricks as reference markers. I use these references to register the scanned images of the film to other data.
I've been using mouse click coordinates to date, but I ...
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STFT Audio processing with zeros
In this paper they preprocess an audio file with a STFT and then apply two equations to the computed matrix.
I tried implementing all of it in python and used librosa for the STFT.
The issue I ...
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Calculate Phase Shift Using FFT
I'm not a specialist in this field and learnt FFT fairly recently.
I want to calculate phase difference of between 1 MHz signals sampled at 4 MHz. The sample counts are both 144. I think the ...
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Plotting a Manually made Spectrogram with python
I'm following a guide about signal processing, but since I'm a fresher to the domain, the guide just stops at a point where only a function that could return the spectrogram values is written. So, my ...
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Resampling to the same sample rate via Python
I'm working on machine learning model and tried to downsample WAV files with Python script, but it didn't work, so I made the simple version - script "resamples" WAV file from 44100Hz to the ...
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