Questions tagged [resampling]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
0
votes
0answers
22 views

How do I change the sampling rate without changing the speed and pitch in Python?

I am building a voice recognition algorithm, and the use case specifies that it should be able to identify the targeted speaker from various audio sources, which means that it must be able to process ...
1
vote
1answer
90 views

How to implement sinc interpolation

I'm trying to write my own high quality audio sample rate converter. I barely know anything about signal processing though so I need help. From what I understand I need to sum together normalized sinc ...
0
votes
1answer
32 views

How to transform a signal to go through specific points?

I have a 1d signal obtained using a Fourier based resample method (TDIFDZP) for which the resampled points don't necessarily go through the original samples. I want to transform the upsampled signal ...
0
votes
0answers
24 views

Resampling with factor linearly moving from one value to another: calculate expected target length

I am resampling an audio (1D) signal, using a resampling factor that moves linearly from startFactor to endFactor; say the input ...
1
vote
1answer
35 views

Oversampling a signal

I’ve built a circuit with an analogue sensor (70 Hz bandwidth) connected to a 24 bit ADC, which is oversampling the signal at 10 kHz. Nyquist sampling theorem implies I should sample by at least 140 ...
0
votes
0answers
26 views

Resampling assessment

I'm trying to figure out which of the resampling methods is best in my job. Comparing the original image vs. bilinear, bicubic, bicubic spline, lanczos. For now I have considered metrics like MSE RME ...
0
votes
1answer
49 views

Upsampling implementation

I have problem with upsampling implementation in the following way: My code: ...
0
votes
1answer
26 views

Upsampling in Python

I'm trying to perform upsampling in Python. Given the signal 's' and factor of upsampling N, I wrote the following code: ...
1
vote
2answers
62 views

Does resampling cause phase shifts?

I have a signal sampled at 40MHz, I would like to resample it to 37MHz. The signal is not periodic, I did resampling with Matalb resample function and it doesn't cause phase shift (as far as I ...
1
vote
1answer
42 views

How to correct for delays in a PAM-X signal with orthogonal CDMA?

I have a receiver which receives data bits at a rate of 5kbit/s. The number of data bits per burst is low (say, 16 bits). These databits are obtained after despreading the incoming signal using an ...
0
votes
0answers
21 views

Evaluate the quality of the satellite image resampling method

I'm evaluating different methods of resampling on Sentinel 2 images for switching from 20m to 10m bands. Comparing bilinear, cubic and lanzcos methods I would like to judge the best result. Several ...
0
votes
2answers
45 views

Downsampling issues

I have this data that need to be downsampled so that it can be fed into a classifier. The issue is that I need to downsample from 1000Hz into 20Hz. If you see the graph below, the blue line is the ...
1
vote
2answers
94 views

Fourier Transform of sampled reflectance measurements

Goal: Calculate the complex index of refraction ($\hat n = n +jk)$ from reflectance measurements. Data: Reflectance measurements for various materials were taken with a FTIR (Nicolet™ iS50 FTIR, ...
0
votes
0answers
13 views

Spectral kurtosis on non-stationary signal

I posted a question some weeks ago I still have not found an answer to. I updated the old question and am hoping someone could help. Link: Varying speed of shaft Spectral Kurtosis
1
vote
2answers
73 views

Rectify signal basic question

When rectifying a signal by squaring it, is it necessary to upsample by a factor of 2? Why is this?
0
votes
1answer
49 views

Upsampling question- Aliasing/imaging problem

I'm trying to study vibrations in a non-stationary shaft by upsampling the original signal. The original sample rate is at 25.6kHz, and it is being upsampled to 36kHz. In the FFT of the upsampled ...
0
votes
3answers
64 views

Interpretation of sample rate

I'm a little confused about the sample rate: If I have an audio file that was recorded with a sample rate of 48kHz, this means that there are 48,000 values per second in this file, right? So when I ...
0
votes
1answer
37 views

Obtaining a high sample rate digital approximation to an analog filter from lower frequency measurements

Consider a set of dense, but generally irregularly-spaced frequency response measurements of some real low-pass analog filter. Denote the maximum frequency for which a frequency response measurement ...
0
votes
2answers
45 views

Resampling of DTFT

I have a constant digital signal that is 1 for every sample and of length 4. 4 point DFT coefficients are $$[4,0,0,0]^T$$ Obviously. I wonder, if I resample the DTFT such that samples are taken at $$...
0
votes
0answers
42 views

Composition of interpolation and decimation matrices

I understand that interpolation is a linear transformation of a signal vector that combines interleaving the elements of the input vector with zeros followed by a filtering operation to remove any ...
0
votes
1answer
81 views

How to Emulate Sample Frequency Offset for OFDM in Matlab?

I am studying the effect of sampling frequency offset on OFDM, and in order to emulate SFO, I have to slightly change the sampling rate of the signal. In order to have a +5ppm offset, I have to change ...
0
votes
0answers
25 views

resample interpolation decimation filters algorithm

I'm creating a program in order to perform Resample, Interpolation and Decimation Frequency. ...
0
votes
0answers
46 views

Weird resampling artifacts of a periodic signal

I am trying to grab time series data from a database storing data on a propritary format. When i chose a resolution which is not a multiple of the power of two of the sampling resolution i get these ...
0
votes
1answer
23 views

Decimating by last interpolating factor? (Multi-stage)

Let's say I have a multi-stage interpolator at the transmitter, which interpolates by 2, 4 and 8 (that is, 64). When decimating (at the receiver) why should I start decimating by 8, then 4, then 2, ...
0
votes
0answers
29 views

Where to do timing synchronization?

I'm trying to do timing synchronization. I was wondering where in the receiver chain I should put this. At the moment, I have (in order, so the first thing in the receiver is 1 and the last is 4): ...
0
votes
1answer
214 views

How to prevent distortion after down-sampling?

I am new to audio signal processing, but in one of my machine learning projects that I am working on, I need to down-sample my audio somewhere in the middle of my neural network. Therefore, I need a ...
0
votes
0answers
41 views

Interpolation FIR filter Remez design criteria

I want to upsample an audio signal by a factor of 8. The technique I was going to use was to upsample by zero stuffing and then interopolate using a low pass anti-aliasing FIR filter designed using ...
0
votes
0answers
57 views

Delay of non-polyphase vs polyphase FIR filters

I implemented a polyphase filter function for interpolating and decimating. It works great (I compared it to what I'd get by interp/decim by inserting L-1 zeros and I get the same results) except for ...
0
votes
0answers
146 views

Polyphase resampling delay

I want to implement polyphase resampling. For this, I wrote a script in matlab. The script performs the following sequence of actions: ...
1
vote
3answers
421 views

Resampling and removing high frequency noise?

I am currently working on a simple sampler that will allow me to load in a wav file and use my MIDI keyboard to play the loaded wav sample at the frequency according to the note played. Now I need ...
0
votes
1answer
100 views

Upsampling and pulse duration

How does upsampling factor relate to pulse duration? If I want to do pulse shaping and I have rcosdesign(beta,span=8,sps=4) should I upsample by ...
3
votes
1answer
194 views

Optimal trade-off between oversampling and filter length

For some sampling-frequency-preserving operations on Nyquist–Shannon sampled signals, such as: a shift a.k.a. translation, and differentiation by applying a derivative filter a.k.a. gradient filter, ...
1
vote
1answer
31 views

Method to rescale signals to mean length

I have a set of signals of varying lengths. I have provided an example of the same below - Their lengths vary between 186 to 202, with a mean length of 197. I am looking to rescale them to the mean ...
1
vote
0answers
21 views

Converting the equalizer coefficients from VSA at 2 sample/Symbol to 1.5 sample/Symbol

I was looking for some feedback on conversion of equalizer/filter coefficients at different sampler rate. Problem Statement: We have built a transmitter system whose output is at 1.5 sample/symbol (...
4
votes
3answers
463 views

Absolute convergence of periodic sinc interpolation

An $N$-periodic complex discrete-time sequence $[x_0, \dots, x_{N-1}]$ can be resampled to an $M$-periodic sequence $[y_0, \dots, y_{M-1}]$ with $M>N$, using sinc interpolation: $$\begin{align}y_m ...
1
vote
0answers
115 views

Why do I have to scale filter coefficients during bandlimited sample rate conversion?

I am writing an example for how to perform sample rate conversion using windowed sinc and polyphase filters. Here is the C++ code as a github gist. So far, this works, and I think I have understood ...
0
votes
0answers
30 views

delayed result in sinc upsampled signal

I have implemented an infinite kernel sinc interpolation. For some signals I notice an artifact, visible at the right end of the plot. I am wondering: is it a bug in my code or a phenomenon usual for ...
1
vote
0answers
241 views

signal interpolation (upsampling) by factor 2

The task is to interpolate the signal by increasing the sampling rate by factor 2. Matlab has a dsp.FIRHalfbandInterpolator function. Let's try using it. ...
0
votes
1answer
364 views

Extrapolate a 2D array using Fourier Transform

I need to extrapolate a given 2D array to a larger domain, keeping the spatial frequency. This is the original field: (the data file in numpy npz format and a Jupyter notebook to plot it can be found ...
0
votes
0answers
53 views

How should I modify my filter coefficients for the filter to be unaltered, when I change my sample rate

I am guessing this is a commonly encountered problem, but I am lost on how to really solve it. I have FIR filter coefficients that are used to match the frequency response of data sampled at 3 kHz. I ...
1
vote
1answer
261 views

Best way to resample an OFDM signal without interpolating + filtering?

I am working on a custom transceiver with a sampling rate of 3.84 MHz (256 OFDM subcarriers at 15 kHz, although 56 subcarriers are null). I would like to resample the signal to 5 MHz, in order to use ...
1
vote
1answer
170 views

Is it possible to lose half the samples, and yet see the full spectrogram as the original signal?

Consider an speech audio signal sampled at 16,000 samples per second. Plot its spctrogram. If we delete every other sample from input signal, we get y[n] = x[2n] for all n. It seems that if we plot ...
0
votes
1answer
92 views

Having Glitches trying to use a Sinc Function Interpolation on a Signal, by chunks of 1024 samples

I am trying to interpolate a signal using a third party lib that performs Sinc Function Interpolation on a signal. It works well if I input all the samples at once but introduce phase distortion if I ...
1
vote
0answers
138 views

Matching two signals with small time drift

I have two time-domain signals sampled at 100 Hz that were measured using two different oscillators and therefore have a time drift between them. I have two synchronization points, one at the start ...
0
votes
1answer
735 views

The condition in order to not loose information after upsampling and downsampling [closed]

If you have a signal x[n] and it is upsampled by N and then downsampled by M. what is the condition for not losing any information in x[n]
0
votes
1answer
1k views

Resampling from variable to fixed-rate [closed]

I have a gyroscope which reports x,y,z values to my embedded device. The rate that one sample appears is variable and has a jitter of around 10ms. However I later want to have a log file with a fixed ...
0
votes
1answer
463 views

Convert 96 Khz to 48 Khz audio: is this simple downsampling method ok?

I have an audio signal x sampled at 96 Khz. I have already lowpassed it with a cutoff somewhere between 20 Khz and 22 Khz, so there should be nothing left of ...
0
votes
0answers
132 views

Resampling or interpolating non-uniform 2D measurements

I am not sure what I should call what I am looking for, but I have some measurements that have 2 independent variables and I would like to get an interpolated value at a specified x,y coordinate. My ...
2
votes
0answers
64 views

How can I extract the 2 polyphase components of a signal after sampling at the half of sampling rate

Suppose I have a continuous signal $x(t)$, which was sampled using sampling function $s(t)$ whose sampling rate is $T_s$.How can I sample the continuous signal by Ts/2 instead of Ts in order to get ...
0
votes
3answers
148 views

Various size arrays interpolation - resampling

sorry if it's stupid question but it’s third day that I try to figure it out how to do that. And just can’t find the solution. Let’s say I have array $A$ size 4, and $B$ size 8. And I need to put/...