Questions tagged [cross-correlation]

The tag has no usage guidance.

87 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
4 votes
1 answer
1k views

How to Find Shift Between Two Signals with Cross Correlation?

I have calculated the cross-correlation function between to waveforms. I would like to find the shift between the two waveforms from the peak of the cross-correlation function. I am not really sure ...
Anks_Eagle's user avatar
4 votes
2 answers
749 views

DOA estimation 2 sources time delay estimation uniform array

I am new to signal processing, so sorry if the question is superbanal. I have been spending more days than I would admit on this and can't find the error. I have two triangle waves that are emitted ...
Irene's user avatar
  • 141
3 votes
0 answers
132 views

Emergence - what constitutes a minimally coherent source that "just begins" to produce stationary interference patterns?

A superposition of two signals with different frequencies will never produce visible (i.e. stationary) interference patterns. Such waveforms will produce spatiotemporal beat patterns, but they rapidly ...
srhslvmn's user avatar
  • 131
3 votes
0 answers
1k views

Fast calculation of normalization factor for normalized cross correlation

There has been a number of posts here I've browsed through that explain implementations of normalized cross-correlation in Python. One such implementation that is frequently cited is found below. <...
batlike's user avatar
  • 213
3 votes
0 answers
111 views

Minimum time delay that can be estimated between two sensors

Consider a 1-dimensional toy problem. I have two sensors at different points along the $x$-axis. Somewhere away from the sensors, a disturbance is created which travels towards the sensors, first ...
RedPanda's user avatar
  • 221
3 votes
0 answers
2k views

Synchronizing signals with different sample rates

I am relatively new to signal processing, so I am still missing some basic knowledge, but I am trying to improve as much as I can. I am trying to synchronize two signals with matlab using cross-...
dsax7's user avatar
  • 271
3 votes
1 answer
936 views

identification of sounds within audio signals

I am looking for methods to identify sounds within audio files. I was hoping to find some ready-made user-friendly software to do this but haven't found it yet. I am familiar with Matlab and some C++...
perigalacticon's user avatar
3 votes
0 answers
150 views

Iterative Auto and Cross Correleation Estimates

I'm looking for literature or other information that covers iteratively estimating the auto- and cross-correlation vectors and the auto-correlation matrix. Initially, I can assume the signal is wide-...
Jim's user avatar
  • 265
2 votes
0 answers
65 views

Estimation of time-varying velocity

Objective: Estimate the mechanical tension of a cable using the velocity of the waves travelling along it. Experimental setup: I have a cable in tension equipped with accelerometers. I measure a ...
User327201's user avatar
2 votes
0 answers
90 views

Blind TDOA Estimation

I am not EE or DSP engineer, however I am working on a project that uses TDOA estimation for location finding. I am able to get the localization algorithm working using cross correlation to estimate ...
Anke's user avatar
  • 21
2 votes
0 answers
166 views

Strange behavior in fixed-point FFT

This is a problem I encountered some time ago while doing my thesis, which still now, I am not sure to understand. By then, I was implementing the circular correlation in an FPGA using this Xilinx FFT ...
danipascual's user avatar
2 votes
0 answers
183 views

Simulink cross correlation issue

here is the Simulink model that i'm using : The matlab function script : function tau = fcn(sig,refsig) tau = gccphat(sig,refsig); The errors :
Nouali Ibrahim Yassine's user avatar
2 votes
0 answers
2k views

Basics of Normalizing Cross-Correlation with a View to Comparing Signals

I'm trying to understand how cross-correlation is used determine the similarity of two signals. This tutorial offers a very clear explanation of the basics, but I still don't understand how to use ...
John Strong's user avatar
2 votes
1 answer
577 views

Finding audio signal time delay: cross-correlation vs. impulse response?

I need to find a time delay between the two audio signals, one comming from one set of speakers, and the other being the source signal that is initialy sent to speakers. I send some noise through ...
Danijel's user avatar
  • 492
1 vote
0 answers
83 views

second order cross correlation

I have two signal sequences $u$ and $y$, where the former is the input to a system and the latter is the output of the same system. I would like to find second-order correlation between the two ...
Neuling's user avatar
  • 103
1 vote
0 answers
55 views

Normalized audio cross corelation

I'm trying to cross corelate two audio files to see where they line up. In scipy im doing: correlation = correlate(audio1, audio2, mode='full') Given the graph ...
Ethan Itovitch's user avatar
1 vote
0 answers
49 views

Channel Impulse Response using USRP(N310) and Gnuradio

I'm attempting to find the Channel Impulse Response using USRP(N310) and Gnuradio. I'm using a single USRP for both transmission and reception. The antennas are positioned 3 meters apart in a hall, ...
Engr786's user avatar
  • 11
1 vote
0 answers
80 views

Finding delay between signals

This should be a simple problem, yet I can seem to figure out what am I doing wrong. I have a bunch of 1-D signals which I expect to look the same up to: shifting, maybe some scaling, and noise. I ...
Yair M's user avatar
  • 305
1 vote
1 answer
83 views

Finding the variance of the normalized correlation coefficient

I saw in Correlation: A Magnitude or Power quantity? post the derivation for $\rho$ (the mean of the normalized correlation coefficient) and its relation to the SNR of the signal. I'm looking to see ...
Idan Uri's user avatar
1 vote
0 answers
64 views

CIR calculation from SDR data: RTL-SDR, bladeRF

We’re developing a prototype using bladeRF and various Python scripts for processing IQ samples. The system works mainly around 2.4 GHz frequencies: Wi-Fi and Bluetooth. One of the needed functions is ...
Oleg's user avatar
  • 11
1 vote
0 answers
59 views

Linearity of the system with Pearson correlation sliding window

I have a sampling system that consists of linear and non-linear components(analog filters, ADC, CPU, and so on). I made some HW changes and I want to verify that the linearity was preserved. My method:...
Michael Shevelin's user avatar
1 vote
0 answers
107 views

Is it possible to normalize an un-normalized cross-correlation vector after computation

I have a C++ code that computes cross-correlation for a given 2 vectors as input. It doesn't have an implicit normalization or normalized implementation of cross-correlation. But I would prefer a ...
skrowten_hermit's user avatar
1 vote
0 answers
115 views

Instantaneous frequency, PLLs, frequency mixing, cross-correlation and the cross-correlation matrix

This is as much a request for comment and critique as anything else. I am looking at tracking how a system perturbs an input that is a (real) sinoid of varying frequency. ...
Knut Inge's user avatar
  • 3,350
1 vote
0 answers
69 views

How to extract information about each constituent 'wave' of a signal?

I have a vector containing wind speeds sampled at 1Hz over ten minutes. I have applied a lowpass filter of 0.25Hz to get only the wind speeds I am interested in. I now want to use MATLAB to ...
Mak Dolla's user avatar
1 vote
0 answers
98 views

Pearson correlation coefficient vs mutual information

I recently computed both the pearson coefficient and the mutual information of two time series as well as the corresponding error bars, and what I find out in the end is a significant level of ...
Johncowk's user avatar
  • 141
1 vote
0 answers
210 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 vote
0 answers
137 views

Time delay estimation of signals increasingly decorrelated

The problem may be summarized as follows: I have a stochastic signals and I want to measure an increasing delay, as depicted in the following picture. The picture represents the signal as it is being ...
LDPC's user avatar
  • 195
1 vote
0 answers
147 views

Subtracting audio signal emitted - trying to use spectral subtraction to localize moving objects

I am a Software Engineer without much signal processing background and currently spending and experimenting to get use to it. My scenario: Assume a speaker and a microphone array. A speaker emits an ...
Deep Mind 's user avatar
1 vote
0 answers
492 views

Frequency Domain Variant of Pearson's Sample Correlation Coefficient?

Suppose that you need to find (i.e. acquire) $x_1$, a short data packet with a known bit sequence preamble (i.e. a PRBS BPSK), in $x_2$, quantized samples recorded from the output of an ADC. You don'...
random_dsp_guy's user avatar
1 vote
0 answers
225 views

Choice of axes in 1D cross-correlation of a signal in a 2D space

I am working on a research project in which we present an observer with a target moving in a random walk in a plane in front of them, and record the eye movements they make to track it. We cross-...
G Pace's user avatar
  • 51
1 vote
0 answers
466 views

Finding lag times for multiple time series

I have $N$ time series which have unknown time offsets relative to each other. I want to estimate the $(N - 1)$ time offsets, $\tau_{i,i+1}$, which maximise the sum of the cross-correlations between ...
Fab von Bellingshausen's user avatar
1 vote
0 answers
1k 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 ...
user2348114's user avatar
1 vote
0 answers
309 views

Cross Correlation shows peak at the same location every time

I have a signal which is taken from an accelerometer and I'm trying to match patterns between different windows of the signal by cross correlation. To do this I take different windows of the signal, ...
user3597574's user avatar
1 vote
0 answers
459 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 (...
Philipp's user avatar
  • 111
1 vote
0 answers
333 views

Fast Normalized Cross-Correlation for Stream-Data

I read some papers about fast normalized cross-correlation techniques. Most of them are used to identify a template in an original image. I was not able to find information about input-data in a ...
F0406K's user avatar
  • 11
1 vote
0 answers
1k views

Why correlation coefficient template matching perfoms better than cross-correlation and square-differences method

I am using this template in OpenCv's match template function by converting all images to grayscale. Here are my result using sum of square differences,cross correlation and correlation coefficient....
Muhammet Ali Asan's user avatar
1 vote
0 answers
3k views

Compare two voices and outline their similarity

I am trying to develop an application which records the voice of someone through a microphone. I will have a preset recorded voices for the same words. I then need to compare the real time recorded ...
mario.borg's user avatar
1 vote
0 answers
543 views

"Circular shift - invariant" distance

Couldn't decide whether the question belongs on Mathematics or here, but I guess I'll ask it here. I've got a discrete - valued function defined on a finite segment of a line that looks like this: ...
Vossler's user avatar
  • 111
1 vote
0 answers
135 views

Time delay analysis in different binary sequences

I am extracting a property of a signal which I represent with either a 0 for absent or 1 for present. This property is extracted for each data point in a time series and in the end I am left with a ...
Tiago's user avatar
  • 119
1 vote
0 answers
478 views

Noisy Signal auto/cross-correlation

I am trying to understand the basics of the cross/auto-correlation if the noisy signal $y(t)$ which is received from the channel at the receiver. Here at receiver we want to estimate the noise in the ...
tuner's user avatar
  • 635
1 vote
0 answers
377 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 ...
user7085's user avatar
1 vote
1 answer
196 views

Increasing samples per symbol degrades correlation between signals

I am trying to implement a simple pseudo-noise (PN) ranging simulation. I have used this GNU Radio example, and I have adapted it a bit to suit my needs. Here is a screenshot of my flowchart: The ...
Slav's user avatar
  • 131
0 votes
0 answers
24 views

Sliding Window correlation vs cosine of relative phase

I create two band limited signals having a specific time-varying covariance at each time point using cholesky decomposition. My aim for this experiment was to show a scenario where sliding window ...
Sir-Lord's user avatar
0 votes
0 answers
34 views

Cross-quantilogram method

What is this method in general? What is the main difference between the quantile cross-spectrum (QS) approach developed by Baruník and Kley (2019) and the cross-correlation function (QS) developed by ...
gurbuz's user avatar
  • 1
0 votes
0 answers
62 views

Similarity between signals

Let's say we have two signals with fast ascending in the beginning, then one slowly decays while another remains at a constant level. An illustration plot is attached. How to compare the similarity ...
colddie's user avatar
  • 101
0 votes
0 answers
72 views

FFT2D on a vector 1D

My question is related to this post I have a 1D vector, the target vector, represented as 2D (knowing the nr of cols and rows) to which i need to apply an FFT2D. Having only the FFT1D, in order to ...
user3253067's user avatar
0 votes
1 answer
112 views

Cross corelation between two complex-valued Time Series Objects

I am exploring the cross correlation function in Julia between two complex-valued Time Series Objects Z1 and Z2 with this simple code: using DSP Compute the cross-...
Bouarfa Mahi's user avatar
0 votes
0 answers
87 views

Cross correlation of OFDM short preamble produces two peaks

I am trying to cross correlate the short preamble of an OFDM transmission. This is the preamble I am using: ...
Aaron3219's user avatar
  • 101
0 votes
2 answers
322 views

Extract a signal from noise, so I can view noise spectrum only?

I have a perfect modulated signal. I have the same signal but with noise, this noise is from non linear amplification. Is it possible, to extract the clean signal so it's just leaving the noise? The ...
njk7's user avatar
  • 43
0 votes
0 answers
78 views

Synchronization for busty signals by correlation methods

I'm trying to reuse standard synchronization algorithms for phase(Costas) and Time (Polyphase Filter bank) for receiving bursty signals. The bursty signals are transmitted every 5 seconds. The signals ...
Moses Browne Mwakyanjala's user avatar