Questions tagged [delay]
The delay tag has no usage guidance.
108
questions
12
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5answers
3k views
Is a notch filter for 50 Hz without delay possible?
I am processing an EEG signal (2 kHz sampling frequency) from hardware and the built-in filter doesn't work as intended. FIR gives a delay, and IIR is unstable.
The signal of interest is from 4&...
0
votes
2answers
36 views
What is effect of fractional sample delay effect on FIR Filters?
In the DSP lecture slides we have this slide:
And
So why this part of FIR Type 2 and Type 4 filter impulse response equation bolded in this slide?
Thanks for your attention.
0
votes
2answers
37 views
How is time or sampling rate accounted for in this model?
A basic model of coupled strings (eg. piano) is provided here as:
The principle is that it has two identical string simulations each formed by a delay line and LPF. The outputs of these are summed at ...
0
votes
0answers
23 views
Problem in finding the delay between two signlas
I'm using find delay block to estimate the delay between two signals.
Here is my configuration parameters :
The error that i'm facing :
0
votes
0answers
23 views
GCC-PHAT for Multiple Sound Sources
Can GCC-PHAT be used to detect multiple time-delays (that is, having multiple acoustic sources simultaneously)? The documentation for the gccphat(sig,refsig) ...
0
votes
0answers
54 views
Calculating output of a digital system signal with a filter that introduces delay
We have a step function at the entrance that goes through the following system. The $D(z)$ digital filter introduces a 0.25s delay. Output as $y(kT)$ must be calculated. How can we tackle this problem?...
0
votes
0answers
23 views
Z transmittance from diffrence equation made out of diagram
I have a problem with getting Z transmittance out of a single block of diagram, when e(nT) is as an input, and u(nT) is as an output. Period of sampling is T = 0.5 s The diagram is:
My first thought ...
1
vote
1answer
75 views
Compensate delay of non-symmetric (non-linear phase) filter
Lets assume I want to apply a matched filter h which is non-symmetric to my signal x and the output is ...
0
votes
1answer
48 views
What factors affect the propagation delay at wireless communication?
Generally, the signal propagation delay is d/c.
d is a distance between a transmitting antenna and a receiving antenna.
c is light speed.
However in NS-3, there is Random Propagation Delay Model
...
3
votes
1answer
204 views
Maximum cross-correlation coefficient value for time delay estimation
I am using cross-correlation for time delay estimation of two synchronized recordings ($x_1$ and $x_2$) of a fixed sound source from two different locations.
I understand that the delay is associated ...
1
vote
1answer
34 views
Plotting phase delay from first principles giving different result from phasedelay() function. Why?
I have a length 10 Finite Impulse response as shown below, and I am trying to find the phase delay of this FIR.
$$h[n]=\begin{cases}0.1,& 0\le n \lt 10\\
0,&\textrm{otherwise}\end{cases}$$
I ...
0
votes
0answers
31 views
Mathematical expression for a system
I have a system that delays the input with k samples and concatenates the new input with delayed one so that y = [x(n) x(n-k)] so if the input comes with n samples the output should be k+n samples. ...
1
vote
0answers
144 views
Implementing real-time variable fractional delay line in Matlab
I am attempting to implement a fractional delay line in Matlab which operates in real time, uses an object-oriented approach, and whose length can be modulated each time a sample is processed. I have ...
0
votes
2answers
162 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
0answers
57 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 ...
0
votes
1answer
621 views
GCC-PHAT (Generalized cross correlation) always peak at delay=0 on real audio signal
I have studied the GCC-PHAT algorithm to estimate TDOA on audio signals at 2 mics.
Here is my MATLAB implementation:
...
0
votes
1answer
232 views
What is the meaning of inverse signal bandwidth?
I have been studying the two ray model in communication systems.
The text I'm studying has two signals, $u(t)$, which is Line of Sight and $u(t-t')$, which is the reflected signal.
It quotes,
...
0
votes
1answer
247 views
90 Degree Phase Shift / Rotation Algorithm for SDR
I'm working on a library to preform frequency demodulation from an SDR signal. I'm using https://github.com/sysrun/rtl-sdr/blob/master/src/rtl_fm.c as a crib for this. The algorithm starts by taking ...
3
votes
1answer
69 views
Is it possible to design a band-pass filter with fewer taps than a series HPF + LPF?
I am digitally filtering a signal that is streaming live. The goal is to reduce the filter delay as much as possible while maintaining the quality of some measurements based on the filtered signal. ...
0
votes
1answer
63 views
How to correct a QAM time delay
How can you correct the anticlockwise rotation that occurs in the received constellation of a QAM system?
My only idea is to compensate the delay with an advance but this is impossible since you ...
0
votes
1answer
38 views
What is the z-domain transfer function of variable delay?
Is it possible to obtain the transfer function of a signal that has a variable delay?
For instance, I have a signal consisting of 10 samples:
0,1,1,1,1,0,0,0,0,1
If I would apply a unit delay to ...
1
vote
1answer
204 views
FIR filter to delay signal [duplicate]
About filter design, mostly we want to control frequency amplitude response and the linearity of phase response. I wonder whether there are FIR filters specialized to delay signal?
For instance, let'...
0
votes
1answer
98 views
Findin the source direction using cross-correlation function
I am new to DSP and I'm working on the following problem.
We have a sound source in the far field and a microphone array consisting of two microphones with distance d. We want to determine the source ...
0
votes
1answer
116 views
difference equation block diagram delay or advance confusion
When does the unit delay, become unit advance essentially.
Goal is to deduce difference equation from block diagram.
Green text is notes about what the value should be in that node of the diagram.
...
2
votes
1answer
507 views
Implementation of a Variable Fractional Delay with Lagrange Interpolation using Farrow Structure
I am writing a C++ simulation software working in time domain. I generate regularly sampled data, and need them to be delayed, in "real-time", by a variable fractional delay.
This is a pretty common ...
0
votes
2answers
3k views
What exactly is a 90 degree phase shift of a digital signal in FM demodulation appraoches?
I am working on an FSK demodulator (1200/2200Hz, 1200 baud) featuring a 90 degree phase shift operation. I don't exactly understand what 360 degrees mean for a digital signal.
My sampling frequency ...
1
vote
1answer
351 views
digital IIR filter delay and oversampling
Can oversampling decrease the delay of digital IIR filter? Imagine there is some digital signal going into processor that applies low pass filter.Lets say its 1 KHz sample rate and the filter is ...
0
votes
1answer
37 views
Dynamics processor for speech - apply gain on delayed samples?
A Dynamics processor (limiter, compressor, expander, and gate) is calculating the output gain at some point in time, and it is applying this gain at some delayed point in time.
This allows for ...
0
votes
1answer
205 views
Emulating a Variable Delay
I am trying to emulate a satellite link where the delay time between the satellite and ground station changes over time due to the satellite's motion. I plan do this by converting to the frequency ...
0
votes
3answers
313 views
Fractional Delay using Polyphase Filter
How to use rectangular window design to design a length-9 polyphase filter which delays an input signal by 3/5 of a sample? An expression for the 9 coefficients is required.
0
votes
1answer
682 views
Converting Time Shift to Phase Shift
I have just started taking signal & systems lessons and here is my question:
If we say that x0(t) = A.cos(w0t). (a cosine signal with zero phase shift, w0 ...
0
votes
0answers
122 views
Bandpass Fractional Delay Filter
I am designing a fractional delay filter, I found this code for lagrange FIR fractional delay filter, The fractional delay filter acts as a low pass filter, it passes low frequencies from 0 to 0.25*fs....
1
vote
1answer
455 views
How to calculate the delay generated by a 2nd order all-pass filter
I'm trying to simulate the dispersion effect of a stiff string in a digital waveguide system, by using second-order all-pass filters.
I use a second order all-pass filter with this transfer function:...
2
votes
0answers
161 views
How can I oversample the received signal by double of sampling time and have two signals
I have a question, how can I make the sampling in Matlab for the received the signal by half of time duration of symbol (Ts), and have two copies of signal (that's the process of fractional sampling ...
1
vote
0answers
285 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 ...
0
votes
1answer
178 views
Audio transfer function modelling with pink noise + signal
I'm trying to model a transfer function for a noisy audio system, specifically to measure delayed system response. Before I can confidently apply control, I need to verify that I can exert control ...
0
votes
2answers
84 views
Calculation of autocorrelation - does calculation “loop”?
With a delay $l$, autocorrelation is defined as:
$$r_{xx}(l) = \sum_{n=-\infty}^{\infty}x(n)x(n-l) = \sum_{n=-\infty}^{\infty}x(n)x(n+l).$$
I want to calculate the autocorrelation of a signal
$$x(n)...
2
votes
1answer
512 views
How to calculate a delay between two signals in frequency domain?
Calculation of a delay between two signals is generally done by finding the maximum in the cross-correlation of the two signals (in time domain):
$$
\tau_{delay} = \arg\max_\limits{t}(f(t) \star g(t))
...
1
vote
0answers
112 views
Sensor fusion under unknown correlations: can covariance intersection account for delays?
Of late, there has been some interest in cooperative estimation algorithms in robotics, where the information sources are usually sensors such as cameras. When multiple robots observe surrounding ...
0
votes
2answers
78 views
audio signal time delay estimation(TDE) in indiviual and separate mics
common TDE problems algorithms(such as GCC) often require audio signals in different mics concurrently, however, is it possible to estimate audio signal time of arrivals(ToA) in different mics ...
3
votes
0answers
73 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 ...
2
votes
1answer
204 views
Can a unit delay in discrete time be represented by exponential functions?
If we have a signal $y[n]$ and its unit delayed version $y[n-1]$, can we write $y[n-1]$ in terms of $y[n]$ times some exponential?
The reason I want to do this is to then take $y[n]$ common and ...
1
vote
1answer
77 views
How to quantify delay in filtered output?
I have a signal containing two sine tones 30 kHz and 60 KHz. I used a second order IIR notch filter to filter out the 60 KHz component from the signal, so now the signal has only 30 KHz component.
...
1
vote
1answer
204 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 ...
1
vote
1answer
1k views
LTI system $y(t)=x(t-T)$ with or without memory
How can I verify if the LTI system ($T$ is a real number, $y(t)$ output, $x(t)$ input):
$$y(t)=x(t-T)$$
is with or without memory? I know that, if $y(t)$ depends only on $x(t)$, the LTI system will ...
1
vote
0answers
91 views
Why prediction by AR model causes time lag
Why does prediction by AR model cause a time lag?
Please tell me why theoretically.
0
votes
1answer
312 views
Compute Power Delay Profile (PDP) from Delay Spread
I have data pertaining to channel obtained from measurements. In order to make use of this data, I need to convert it into a form as follows:
...
0
votes
1answer
271 views
Time variance of $y(t)=x(2t)$
At first I had trouble proving the time variance for this as I would do the usual mistake as in question Is the system represented by the equation $y(t) = x(2t)$ time invariant?. The solution has ...
1
vote
0answers
112 views
How to find and fix the delay of a modulation
I am creating a model in MATLAB to simulate power line communication, but I found a problem. I'm very new to the DSP area, I get my code below from a MATLAB example.
...
0
votes
1answer
226 views
Successive dynamic time warping with a set of window sizes
I am applying DTW to a set of data. I haven't figured out a solution yet, still searching for ideas, and I'm currently trying to apply DTW successively with a monotonic set of windows.
Let's say i ...
