Questions tagged [delay]
The delay tag has no usage guidance.
3
votes
1answer
36 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
17 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
13 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
35 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
32 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
27 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
136 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
583 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
91 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
32 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
57 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
93 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.
-1
votes
1answer
48 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
53 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
208 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
67 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
138 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
0answers
49 views
Sharpened CIC, implementation in Matlab
Background:
I am interested in sharpened CIC filters. I found this thesis A power efficient polyphase sharpened CIC decimation filter for sigma-delta.
Now I want to implement a sharpened CIC (SCIC) ...
0
votes
1answer
96 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
48 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
$$x(n)...
2
votes
1answer
165 views
How to calculate a delay between two signals in frequency domain?
Calculation of a delay between two signals is generally done by finding the maximum in the cross-correlation of the two signals (in time domain):
$$
\tau_{delay} = \arg\max_\limits{t}(f(t) \star g(t))
...
0
votes
0answers
44 views
Delaying FFT by a specific delay factor in simulink
How do I delay FFT samples by a specified delay factor in Simulink?
FFT output length [32768x1] appearing one value at a time (as a scalar). Delay factor length [32768x1] appearing one value at a ...
0
votes
0answers
20 views
Average delay in skewed cross-correlation function with phase lag zero, plus example
I am calculating the cross-correlation function (CCF) between two digital signals in the following way:
$$CCF(τ) = r(M(t),N(t+τ))$$
where $r$ is the Pearson correlation, $M$ and $N$ are two signals, ...
1
vote
0answers
54 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
0answers
43 views
How can i find the time delay using spectrogram?
We observe that in the first plot we have a delayed signal and in the second one, his spectrogram. My question is how can i find the time delay using spectrogram. I understand that if i sum the colums ...
0
votes
2answers
65 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 ...
0
votes
0answers
40 views
Delay compensation in wavelet decomposition
I am working on wavelet based ECG delineation and I'm trying to implement the algorithm developed by J.P Martinez.
I'm applying a quadratic spline wavelet and using the atrous algorithm(using the swt ...
0
votes
0answers
163 views
Subsample phase correlation method for time delay estimation / image registration
I'm trying to implement the subpixel registration method discussed in this paper, towards estimating time delay in a 1d signal. In a nutshell, to find the shift between two vectors $f$ and $g$, one ...
3
votes
0answers
48 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 ...
0
votes
0answers
43 views
synchronizing sender's and receiver's signal using cross-correlation
I'am attempting to synchronize the timing instance of the sender's and receiver's signal in a communication channel, i.e trying to find the lag(timing delay-as the clocks are not synchronized) at the ...
2
votes
1answer
112 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
54 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
148 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 ...
0
votes
0answers
149 views
Can't understand allpass filter
I have a very bad question, but please, bare with me. I'm measuring power consumption in my house using CTs for measuring current, which lags current phase by 6° approximately, so I want to apply an ...
0
votes
0answers
59 views
Time delay estimation using two sets of signals?
I am quite a newbie in signal processing and I run into some problem that I am not sure how to solve it. So here goes,
I have two sets of noisy signals, let's call it $x(t)$ and $y(t)$. And another ...
1
vote
1answer
263 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
71 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
161 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
183 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
81 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
156 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 ...
0
votes
2answers
143 views
Dynamic Time Warping of inverted binary signals
I am trying to find a match between a reference binary signal and a large set of data. From experience, the reference signal can appear time-shifted(that is why I've chosen dtw) and inverted, meaning ...
4
votes
2answers
475 views
Flat fading criterion of OFDM subcarrier spacing
I have always thought that the OFDM subcarrier spacing $\Delta f$ is chosen such that
not too small because Doppler spread can destroy subcarrier orthogonality
not too large to avoid Cyclic Prefix (...
0
votes
1answer
315 views
Maximum likelihood estimator of active time delay and passive time delay
A typical time delay estimation problem has the model:
$$
\begin{align}
x_1(t) &= s(t)+ n_1(t) \\
x_2(t) &= a s(t-D) + n_2(t)
\end{align}
$$
Where $n_1$ and $n_2$ are considered to be ...
3
votes
2answers
343 views
Confused with filtering linear chirp signal using band-pass filter
everyone. Recently, I am doing simulations about filtering a linearly chirp signal, and have been confused about the result. The signal was linearly chirped from 0 to 1000 Hz.
At first, the chirping ...
3
votes
1answer
141 views
Regarding the advantages of generalized linear phase filters
I know that for a linear-phase filter with frequency response given by
$$H(e^{j\omega}) = |H(e^{j\omega})|e^{j\phi(\omega)} $$
if the input of the system is
$$x[n] = s[n]\cos[\omega_0 n] $$
where $s[...
0
votes
0answers
45 views
Finding lossless coefficients to multi-tap feedback delayline
I have a digital delayline code which looks like this:
...
0
votes
0answers
69 views
How to Statistically Test Delay Between Two Groups of Signals?
Imagine there are two groups of signals A and B that have three samples each.
...
4
votes
1answer
558 views
Time delay estimation in low SNR
So I am interested in finding delay between two noisy narrowband signals,for example, two arterial pulse waveform. I can easily get a correct estimate of delay using cross-correlation method, but it ...
2
votes
1answer
47 views
Books on delay / lag compensation
Which books do you recommend that provide comprehensive overview of delay compensation techniques in control systems?
