Questions tagged [signal-detection]

The tag has no usage guidance.

89 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
5
votes
2answers
908 views

How to calculate the phase shift AND time delay of non-periodic signals

Say I have two non-periodic signals, $f_1(t)$ and $f_2(t)$, with Fourier transforms $F_1(\omega)$ and $F_2(\omega)$. Basically, I need to line up $f_1(t)$ and $f_2(t)$ as close as possible, and I am ...
4
votes
0answers
95 views

Finding the parameters and endpoints of a sinusoid

Suppose I have some signal $$ s(t) = n(t) + \left\{\begin{aligned} &0 &&: t < t_0\\ &A e^{i (2 \pi f t + \theta_0)} &&: t_0 \le t \le t_1\\ &0 &&: t > t_1 \...
3
votes
0answers
27 views

Inconsistant Variation in BLE Beacon RSSI Values for Distance Measurement

I am developing an application to estimate the distance to a BLE Beacon using its RSSi values measured from a Mobile Phone. But when I started to collect data I could see that they varied so much that ...
3
votes
0answers
146 views

Multilateration of Sound in 3D Space

TL:DR - How can you find the 3D coordinates of a emitter than transmits an impulse signal? STORY: I'm working on something to improve my bird-watching. I've got a camera that can take pictures of ...
3
votes
0answers
95 views

Energy Detection in Presence of Colored Gaussian Noise

Before asking my question, let me introduce the context: For spectrum sensing based on energy detection, which has been widely studied in presence of AWGN, the optimal detection threshold is computed ...
3
votes
0answers
630 views

Incorrect Frequency results when using Multiple Signal Classification (MUSIC)

I am using MUSIC (Multiple Signal Classification) to determine Direction Of Arrival (DOA) and frequency of signals impinging on an Antenna Array. I am using a function ...
3
votes
0answers
242 views

Segment/Idenfication of signal from a spectrogram

I have the following Spectrogram of a signal: Essentially, in this signal, I know there is one point of interest (between 60-80) and between the the particular frequencies. I could, potentially ...
3
votes
0answers
59 views

Intuition of Location on the Conic Axis TDOA solution

In an old paper "A New Approach to Geometry of Range Difference Location", there is a mathematical derivation that does not include any mention of the relationship to the underlying problem. In the ...
3
votes
0answers
800 views

calculate root mean square, ratio of power, constant false alarm, … of a signal

I am new to Digital Signal Processing, and am reading a paper. I don't know how they can extract some features from signal, like root mean square (RMS), Constant False Alarm Rate - CFAR, Mean Value ...
2
votes
0answers
36 views

How to remove varying noise from strain data in MATLAB

I'm very new to signal processing. I have some data measured over time at 800 Hz. I'm interested in the high frequency signals. You can easily identify them in the image below (in this case, 3 signals)...
2
votes
0answers
63 views

ESPRIT signal subspace and rotational invariance

so in ESPRIT[1,2] we have some signal of the form: $$y[n] = \sum_{k=1}^{K} a_i(k) e^{j\omega_k n} + N[n]$$ where N is noise, then we get the autocovariance matrix $$R_{yy}=E[y[n]y[n]^*]$$ take the ...
2
votes
1answer
50 views

BER performance of fractional equalizers for colored noise

I am trying to compare the BER performance of fractional and symbol spaced equalizers for channel equalization in colored noise scenario. I have found from simulation that for positively correlated ...
2
votes
0answers
59 views

Is there in signal processing similar method than Otsu's method in image processing?

I'm just wondering that is there any similar method for separate signal and signal+noise in signal processing like otsu's method set threshold to valley of image histogram? And if there is how can I ...
2
votes
0answers
514 views

Peak detection techniques

I'm using a cell-averaging constant false-alarm rate (CA-CFAR) detector to detect peaks like the first one in the following plot: The magenta line is the adaptive threshold, which is the local ...
2
votes
0answers
54 views

Supervised instrument recognition

Is it possible to use NMF for a sort of supervised polyphonic instrument recognition? I have training data for a timpani and training data for a bongo (or a bongo, snare and box drum). How can I ...
2
votes
0answers
46 views

Signal conjugation detected on RF recording samples, why?

I collected spread spectrum signals at 400 MHz at low elevation angles using Software Defined Radio complex sampling over the seasons. I noticed that over watery, icy surfaces, the RF samples are ...
2
votes
0answers
108 views

Is there a way to apply blind source separation using ONE mixture?

This question is a follow-up for my previous one: Reduce the "glare" effect of a receiver within a system. I have broken the problem into pieces and I humbly think that I've got a way to ...
2
votes
3answers
150 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 ...
1
vote
1answer
38 views

Telling apart a right traveling non-periodic signal from a left-traveling non-periodic signal, with a background periodic signal

I have a time-signal sampled over a one-dimensional spatial domain $x$. I know it is made of 3 components: a right traveling non-periodic wave (characteristic time width $T_{R,NP}$, mostly 0 outside ...
1
vote
0answers
42 views

Detecting complex signal within complex AWGN using Neyman Pearson statistic

I need to construct a Neyman Pearson statistic for detecting a complex signal with known amplitude and unknown phase in additive complex Gaussian noise. My hypotheses are: \begin{align} \mathcal{H}_0 &...
1
vote
2answers
64 views

Typical shape detection algorithms

Here is my target, given a set of consecutive discrete 1-d data points within a window. I want to know whether there are good algorithms to detect certain typical shapes of the signal in the window. ...
1
vote
2answers
63 views

Algorithm for detecting whether a signal stored in rolling buffer is Increasing, Decreasing or staying Constant

I have a data signal which is generated at constant time interval. It is a real world measurement and thus exhibits some noise in its value (it fluctuates approx + or - 20 units). The noise is fairly ...
1
vote
0answers
55 views

MFCC parameters for gunshot recognition

I'm writing a gunshot detector software. I'm using this article as reference:https://arxiv.org/ftp/arxiv/papers/1706/1706.08759.pdf. For now, my software is able to recognize an impulsive sound. Now, ...
1
vote
0answers
93 views

Extracting signal from data using Otsu thresholding in MATLAB?

I am very new to signal processing. I am trying to extract a signal from my data using otsu threholding but it's not fully accurate. In this case I know that there is going to be a single signal in ...
1
vote
0answers
84 views

Is there a situation when maximizing SNR doesn't also maximize probability of detection?

The problem I'm working on is signal detection of a radar signal, but I suspect this problem shows up in many different branches of signal processing. Background: From [1], the factor $I_f$, by ...
1
vote
0answers
43 views

Required number of measrments for signal recovery in a compressed sensing MMV problem?

For multiple measurement vector (MMV) problem $Y=AX$ where $A$ is $m \times n$ sensing matrix and $X$ is $n \times L$ matrix haveing K non zero rows. What are the necessary conditions on the ...
1
vote
0answers
69 views

Sufficient conditions for exact signal recovery using OMP?

For a compressive sensing model : $$y_{_{MXN}}=A_{_{MXN}}x_{_{NX1}}$$ where $x$ is $K$ sparse, what is the sufficient condition for Orthogonal matching Pursuit (OMP) to exactly recover the data for ...
1
vote
0answers
46 views

Source localization in 3d

Let's say I have a 4-sensor square-shaped array in 3d space, with sensors at $$ s_1 = [1 \ 0 \ 1] \\ s_2 = [2 \ 0 \ 1] \\ s_3 = [1 \ 0 \ 2] \\ s_4 = [2 \ 0 \ 2] \\ $$ And a single source somewhere ...
1
vote
0answers
512 views

How to detect overall error between two signals and also track changes occurred

I need to develop an algorithm that will compare two signals (1 Reference Signal and other is measured signal values from sensor) and generate some metric(s) to describe changes between them. I am not ...
1
vote
0answers
120 views

Best Method to Separate square wave and smooth wave

I have a signal consists of a smooth wave and square waves. Is there comprehensive method can separate square wave and smooth signal? I looked for the likelihood ratio test but cannot find any ...
1
vote
0answers
25 views

Classification test by embedding true positives in high frequency recordings

I'm evaluating a cyclostationary approach to signal classification. My first step in doing so was generating signals and embedding them into a few specified parameter sets of the Watterson channel ...
1
vote
0answers
825 views

Detecting delay and sample drift in audio files (wav, mp3, etc.)

In my application, I have an audio recording with background music. I know which song is playing in the background and have a copy of the original song (wav, mp3, etc.). The goal is to align the ...
1
vote
0answers
48 views

How does the error in azimuth angle vary as one moves away from the boresight direction of a radar

My question is basically same as the title. I am trying to find a mathematical model which provides the error, $d\theta$, in azimuth angle($\theta$) as one moves away from the boresight direction of ...
1
vote
0answers
94 views

Received signal envelope PDF to power PDF [Wireless Communications]

I am deriving the probability density function (pdf) of the received wireless signal envelope in multi-path fading channels. I wish to transform this envelop PDF to the power PDF of that signal. I ...
1
vote
0answers
254 views

Can we use SVD to solve single channel deconvolution problem?

I have seen using singular value decomposition (SVD) to solve deconvolution problem for example truncated SVD (TSVD) . It appears there is also a connection between Tikhonov regularization and SVD. My ...
1
vote
1answer
143 views

Detecting expected patterns in repeated measurements

I am new to signal processing and I am trying to learn myself. To understand what i am interested in, let me show this on example (note that this is just a random example to illustrate). Here is some ...
1
vote
0answers
322 views

Event detection in a running person's acceleration data

I am trying to detect some events on this signal : This is the acceleration of someone running. By eyes we can detect many blocs, sometimes separated by a little interval. I would like to be able to ...
1
vote
0answers
373 views

Audio - TDOA and $\tt xcorr$, find the 'best' peak

I try to locate a mobile device using multilateration. The mobile device acts as the receiver and in the room I have three speakers. To calculate the position I need the time difference of arrival (...
1
vote
0answers
108 views

Detecting special points in signal

What tool/filter/mathematic operation would you use to detect the red points marked in this signal? As you can see there are several differentiated groups and I want to detect those moments in which ...
1
vote
0answers
444 views

What is the best algorithm to detect leading edge?

I am interested to detect leading edge of one dimensional signal. There may be several algorithm for edge detection, specially for image processing (2 dimensional), but my interest is on one ...
1
vote
0answers
65 views

General question on signal processing guidelines for emergency shutdown applications (i.e. medical devices)

Disclaimer This might be a very broad question. I ask it out of curiosity, because the topic came up in a discussion lately. Hence, I do not have any specific applications or even data that I could ...
1
vote
0answers
46 views

How do I correctly receive a signal using a signal analyzer?

For the past few weeks, I have been trying to send a Zaddof Chu signal using a vector signal generator, and receive it using a signal analyzer. Both devices are made by R&S. However, the signal ...
1
vote
0answers
78 views

Heterodyne detection

Prove that with appropriate choices of the phase $\varphi$, one can recover the quadratures of $m(t).$ Attempt The context of this question is weak optical signals combined with a strong local ...
1
vote
0answers
88 views

processing photo diode array data

We have designed a system which has an 8X8 array of photo diodes, we sense 10ns pulses of laser falling on those photo diodes with a repetetion rate of maximum 50Khz i.e. 20us, we were successfully ...
1
vote
0answers
94 views

Application of BIC, MDL, AIC

I understand that mathematical motivation behind Bayesian Information Criterion (BIC), Minimum description length (MDL), Akaike information criterion (AIC) are different but I am assuming that there ...
1
vote
0answers
38 views

Variation in Signal Power in Mimo system

I am exploring methods for reducing computations required by MUSIC (Multiple Signal Classification) Algorithm. Most of the computational power is spent on calculating SVD. My approach is to take ...
1
vote
0answers
58 views

determining walsh function components of signal after passing through non linear process

When a sum of sine waves is passed through a non linear process, harmonics and intermodulation distortion products are created, which are visible when applying an FFT to the signal. This causes ...
1
vote
0answers
305 views

Train Pulse Recognition in Medium Voltage Networks

I just started a project in the Smart Grids area. It involves the recognition and quick extinction of earth faults in a medium voltage system. The system works automatically and pretty much gets rid ...
1
vote
0answers
172 views

how to detect the center frequency of a QRS complex in an ECG signal?

i want to design a filter that can effectively detect the QRS complex in ECG signal(whose Fs=360Hz) and reduce high frequency noise components. i want to know as to how the center frequency is ...
0
votes
0answers
12 views

Decoding packets in Long Mode Range

Im using CC1350 launchpad microprocessor of Texas Instrument that I configure my transmitted packets using SmartRF studio Im trying to decode my packets for verifying if my transmitted packet is valid ...