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What is the support detection probability after sparse recovery using OMP and Random sampling

I am working on Compressive spectrum sensing CSS. I performed random sampling, OMP recovery. The detection is done by finding nonzero amplitudes in the recovered spectrum to decide the belonging of ...
BENZATER hadj's user avatar
0 votes
0 answers
23 views

frame size and hop size mismatch with aubio pitch detection algo

I am writing a script that detects the pitch of a short file as part of a larger project. I want to detect using an external call to sox and using the crepe, aubio, and librosa libraries. Aubio is ...
Rich Rath's user avatar
4 votes
1 answer
106 views

Detection problem with extra noise observation. Does the extra observations help with detection?

Assuming all “real” number, consider the detection problem of $x$ given $y_1$ and $y_2$ below $y_1= x + n_1$ $y_2= n_1 + n_2$ where $x$ is either $+A$ or $-A$ with equal probability, and $n_1$ and $...
Jacob's user avatar
  • 121
4 votes
0 answers
154 views

Reed-Solomon: a combination of error correction and detection in the CD CIRC algorithm

It's well known that, with 4 redundant symbols, a Reed-Solomon decoder can either correct 2 incorrect or detect 4 incorrect symbols. In "The Compact Disc Digital Audio System: Modulation and ...
Tom Verbeure's user avatar
0 votes
0 answers
60 views

Symbols to samples at the transmitter and samples to symbols at the receiver

Suppose I have the $N\times 1$ vector $\mathbf{x}$ that contains binary phase shift keying (BPSK) symbols each with power $P_s$ Watts. At the transmitter: I want to convert these symbols into samples ...
Math_Novice's user avatar
0 votes
0 answers
62 views

MIMO Radar - Using statistical properties of the Fourier transform phase for detection

I currently researching the phase (between real and imaginary part) of the fourier transformation. It seems that one can use it for detection. For the signal processing I use two fft transforms. One ...
magi's user avatar
  • 1
0 votes
1 answer
129 views

Interpolating Filter for Quadrature Detector with one ADC

Single ADC is sampling at 16000 Hz the I and Q outputs of quadrature detector. So each I and Q signal is sampled at 8000 Hz, with phase offset 90 degrees between them. Bandwidth of interest is 3400 Hz....
K-man's user avatar
  • 27
1 vote
1 answer
36 views

AWGN continous time channel + colored noise

I'm working on an exercise but I'm stuck at the question where the noise becomes colored, can someone help me ? Let $\{\psi_1(t) = \mathbf{1}\{t \in [0,1)], \psi_2 = \mathbf{1}\{t \in [1,2]\}\}$ be an ...
Bozu's user avatar
  • 15
5 votes
2 answers
99 views

Slicing an Image into Tiles According to Content

Given an image that contains an NxM grid of icons with text below them, somewhat like this: I'm wondering how to split it up into the individual icons with text. Some wrinkles: The image won't ...
bjnord's user avatar
  • 161
1 vote
1 answer
855 views

MIMO detection using ZF and MMSE

I have a problem related to my uni assignment. The task seems rather simple - plot SER as a function of Es/N0 for 2x2 MIMO and 16-QAM modulation assuming AWGN noise and Rayleigh flat-fading channel. ...
Pawel's user avatar
  • 35
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0 answers
22 views

Lung Detection and Segmentation in X Ray Image

I'm a beginner in image processing and I have to create a segmentation algorithm to detect lungs from an image . Image given : And after removing the noise from the image and applying a threshold the ...
bill's user avatar
  • 1
-1 votes
1 answer
124 views

Questions about minimum detectable RF signal level

I would like to estimate the ideal minimum detectable power levels for a few different tuners. I am wondering the best way to go about doing this just by using well-known engineering equations along ...
reacher33's user avatar
0 votes
0 answers
18 views

Trim syllable audio recording to only the vowel

For a Chinese learning app, we let users record a syllable and we use speech recognition to assess if the pronunciation was correct or not. Every Chinese syllable can be pronounced with different ...
Paul's user avatar
  • 1
2 votes
1 answer
213 views

Why does my PLL simulation oscillate after locking?

I'm working on a crude circuit simulator with the goal of implementing PAL encoding and decoding, so that I can experiment with generating images that look like video transmissions. In the simulation ...
Polynomial's user avatar
4 votes
1 answer
185 views

How to detect the presence one- and two-dimensional patterns in distributions of spatial points?

I have many point patterns, and I want to detect those patterns that have points arranged in lines that may be curved, intersected or broken. For example, on the following picture, the upper left ...
Vladislav Gladkikh's user avatar
0 votes
1 answer
53 views

mathematical expression to detect modulated data within a vector

Assume I have such modulated data which is, for example, $x=0.7+0.7i$. That modulated data is encapsulated in a vector as below: OR where $c$ is any constant number, let’s say, for example: $c=0.7$ ...
Fatima_Ali's user avatar
0 votes
1 answer
312 views

What is the difference between object detection and target detection? Are they the same thing?

I was reading some articles regarding object detection and target detection and have a hard time understanding the difference between object detection and target detection. i want to know whether they ...
asif's user avatar
  • 1
1 vote
1 answer
59 views

where we use estimation and detection in communication system?

I read from the book that we use estimation when we are dealing with analog signal or continuous random variable and the term detection when the transmitted signal is a discrete value even if a ...
Anil's user avatar
  • 13
2 votes
1 answer
245 views

Find gaussian in data

I have some time series data (blue line lower plot) with a gaussian added into it (red line upper plot). I would like to estimate where the gaussian is in the data, and the height of the gaussian (...
Voltage Spike's user avatar
0 votes
0 answers
351 views

Maximally Stable Extremal Regions (MSER) Implementation in Document Image Character Patch Identification

My task is to identify character patches within the document image. Consider the image below: Based from the paper titled "CG-DIQA: No-reference Document Image Quality Assessment Based on ...
alyssaeliyah's user avatar
4 votes
2 answers
479 views

Detect a Frequency Change in a Step Wise Frequency Chirp

I am driving a system with a step-wise frequency chirp from 50-400 hz with a frequency step of 0.01 hz. I am having difficulty identifying the points of frequency change as the data collected has an ...
Jon's user avatar
  • 41
1 vote
1 answer
93 views

Projecting a vector to another to detect the sparse values of such vector

Assuming we have sparse vector of length $N$ such as $X = [0,1,0,-1,0,1,1,0]$ which has some non-zeros values. The vector $x = iFFT(X)$ is convoluted with another vector $h$ resluting $y = h*x$. ...
Gze's user avatar
  • 640
3 votes
3 answers
260 views

pitch detection: which is the most robust way to distinguish voiced from unvoiced audio

I am trying to write a voice/whistle driven synth but I am struggling with pitch detection. As a premise I must say I am quite skilled and experienced at dsp coding plus I have pretty read almost ...
elena's user avatar
  • 351
1 vote
1 answer
759 views

Detect low power DSSS-BPSK signal

I have heard that it is possible to detect a low power (ie not visible on a spectrum analyzer) DSSS-BPSK (direct sequence spread spectrum) signal even when you don't know the spreading code by ...
random_dsp_guy's user avatar
2 votes
1 answer
527 views

Absolute value based AM envelope detection viewed in the frequency domain

In my understanding when a passband AM signal is demodulated with an envelope detector taking the absolute value restores the original baseband version of the signal and the low-pass filter removes ...
axk's user avatar
  • 237
0 votes
0 answers
128 views

lock in detection based denoising using matlab?

What are the limitations of implementing the lock in detection technique in matlab? I have time varying data with known frequency with huge background noise. The reference signal is also available. ...
ACJ's user avatar
  • 1
0 votes
1 answer
46 views

Synchronize device to audio stream - Approach

I am working on a device which's actions should be synchronized to the audio played. The audio stream is known in beforehand and can be altered to contain signals for the synchronization. But the ...
Gerrit's user avatar
  • 3
0 votes
1 answer
207 views

What is the type of each 4 different noise signals that are shown below?

I am looking at four different noise signals. I got them in a time domain and they are different. I went to the frequency domain and found the fft for all four ...
SnowMan's user avatar
5 votes
1 answer
2k 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 ...
Jung_Zheng's user avatar
0 votes
2 answers
3k views

How do I measure the amount of information within an image?

I'm trying to find some information threshold that is required for performing detection of objects in images. However, I'm not sure how exactly to quantify the amount of information contained within ...
Mark.F's user avatar
  • 113
1 vote
0 answers
745 views

Generating a colored waveform of an audio file?

I would like to ask on what approaches could one attempt to generate a colored waveform out of an audio file. Below are two examples of waveform coloring by commercial products along an audio sample ...
aybe's user avatar
  • 284
1 vote
0 answers
224 views

Threshold for CAF Surface

I am calculating a time partitioned Cross Ambiguity Function (CAF) by adding the surfaces of different time-sectioned CAFs together. Meaning, I calculate a CAF using 10 seconds of IQ data, calculate a ...
jeremy's user avatar
  • 509
-1 votes
1 answer
432 views

Does flat surface detection and orientation require special hardware to compute?

Modern augmented reality platforms such as Google's ARCore and Apple's ARKit seem to only operate on mobile devices, I'm guessing, because their underlying algorithms require specialized hardware that ...
hotmeatballsoup's user avatar
0 votes
0 answers
905 views

How to set sigmas and kernels for 3D-Laplacian of Gaussian filters to blob detection in Matlab?

I have written code according to a paper for Lung CT images, but its output wasn't correct. I think it is because of the setting of its parameters. The paper is about a multi-scale method using a ...
Ellie's user avatar
  • 101
1 vote
1 answer
752 views

CFAR Detectors and Interference

Constant False Alarm Rate (CFAR) is an automatic thresholding technique. It's situated after the FFT processing in other to detect target peak. This probability of detection depends on clutter and ...
Issa's user avatar
  • 127
1 vote
1 answer
56 views

Voice masking for removing voice and not birdsong

First the problem I'm tyring to solve: I'd like to find a way of removing any potential noise from audio files recorded in noisy environments where we are trying to record birdsong. This is for the ...
Finn Maunsell's user avatar
7 votes
3 answers
9k views

How detect signal from noise?

I'm trying to detect when a signal is "on" from samples I have. Those samples come from a software defined radio, if that matters, and the signal i'm trying to detect is a WiFi signal. The problem is ...
user35067's user avatar
0 votes
1 answer
332 views

Pulse duration detection

I have a signal sequence where multiple pulses with different amplitude and duration may occur at random times. White noise is present as well. I was searching for a Matlab function which could detect ...
DbegOber's user avatar
0 votes
1 answer
1k views

Probability of False Alarm versus SNR

I'm currently testing the performance of an energy detector using two tests. One test involves finding the optimal threshold to achieve a probability of detection(Pd) of 0.9 and a probability of false ...
Tellrell White's user avatar
2 votes
1 answer
562 views

Getting started with wavelet-based real-time anomaly detection for temporal signals using Python

I have an anomaly detection problem I wanted to consider addressing in software (python) with wavelets. I’m new to wavelets as well as the python’s spicy.signal wavelet package, let alone with the ...
rhz's user avatar
  • 457
0 votes
1 answer
50 views

How to choose good features for my machine vision application? [closed]

I am trying to create an application (with OpenCV3) that can distinguish sidewalks from streets by a real-time camera that is embedded in a glass. I have 3 question about this project: Which features ...
user3486308's user avatar
1 vote
1 answer
1k views

finding frequency range and dominant frequency of a stored signal

I have sEMG signals, captured from commercially available device. the signals are stored in .tdms file format. i want to varify whether the captured signals are really sEMG (or simply EMG) signals or ...
Javeeria's user avatar
3 votes
0 answers
159 views

Unbiased estimation of square in presence of Gaussian noise

I have a single scalar observation, $y$, of a scalar parameter $x$ in presence of additive Gaussian noise. That is $y = x + n$ where $n$ is the Gaussian noise. The variance $n$ is known to be $\sigma^...
SRT's user avatar
  • 131
2 votes
1 answer
37 views

If I line in the sound from a video game console, can I detect when a sound is played?

The question is as the question is. It won't be this isolated sound though, it'll be a sound on top of background music. I think I can get a hold of the sound file itself from the data, but at worst I'...
Zyst's user avatar
  • 21
3 votes
2 answers
2k views

How to reliably detect the state (opened or closed) of sliding doors from a statically-positioned video stream

I have a mounted (static) camera that has a view of a set of sliding doors. Since doors are rectangular in nature, and they don't have many degrees of freedom, this seems like a problem that should ...
Jim's user avatar
  • 131
1 vote
2 answers
1k views

Detect marker orientation inside an image

I've been reading how augmented reality works and how markers are detected. Anyway I can't find any resource that would help me in detecting an arbitrary complex image as, for instance, a book's cover....
Dean's user avatar
  • 125
0 votes
0 answers
125 views

Another pitch detection problem

I'm a french student and I have to make a scientific project in group, so we decided to work on how automatically turn sheets music when a musician reaches the end of the page. For that I'm working on ...
Hugo Pauget's user avatar
1 vote
1 answer
2k views

How to determine the symbol rate of a 2-FSK signal?

Let's say that I have a 2-FSK signal recorded so that the SNR is around 20 dB and the noise seems to be more or less white. The distance between tones is greater than the minimum distance needed for ...
AndrejaKo's user avatar
  • 206
1 vote
1 answer
3k views

How do spectrum analyzers detect peaks?

Using peak search, I'm able to put the cursor on any of the several peaks on the spectrum analyzer display. I am trying to do something similar in software, with the output of the FFT of the radio ...
Ken - Enough about Monica's user avatar
0 votes
1 answer
1k views

What's wrong with this Average Magnitude Difference algorithm?

I implemented this Average Magnitude Difference algorithm in Javascript ...
Adriano Di Giovanni's user avatar