Questions tagged [bandpass]
A band-pass filter is a device that passes frequencies within a certain range and rejects (attenuates) frequencies outside that range.
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Minimum bandpass bandwidth?
Is there any restriction on decreasing the bandwidth (beyond the sampling rate) that I should be aware of when filtering a signal with a bandpass? My intuition tells me that the quality of the result ...
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Doubts about digital signal processing methodology
Disclaimer: I'm a beginner at all of this.
I am working with vibration data from accelerometers recorded at a sampling rate of 1600 Hz and the vibrations are induced by a source within the range of 20-...
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Online algorithm to detect non-directional volatility?
I'm trying to write an online algorithm to detect when a time series goes sideways (i.e., its mean trend or mean drift is approximately zero) but is also unusually volatile. For example, in the red ...
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How do I use this bandpass filter? [closed]
I found this free DSP book by Rutgers University professor Sophocles J. Orfanidis. The book is called Introduction to Signal Processing and the link contains many different implementations of common ...
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Why is there a dip in this Chebyshev filter response?
I want to build and simulate a 6 GHz, 4th order lumped-element Chebyshev bandpass filter with a maximum passband ripple of 0.1 dB and a bandwidth of 1 GHz, and as I understand it, there should be 3 ...
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How to calculate SNR variation with period?
I want to calculate the SNR variation of a signal with respect to the period. The current technique I am using is calculating SNR iteratively by applying narrow bandpass filters of different range, ...
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What is the relationship among digital filter cutoff frequency, signal frequency and filter settling time?
I have some general observations but I am asking if anyone can summarize more conclusively:
(1) Filter settles slower if the ratio between signal frequency and filter cutoff frequency is smaller;
(2) ...
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Are there any recommended filter types for passband frequencies near Nyquist?
Is there a recommended filter type for frequency bands near the Nyquist frequency?
I have been trying to design complex passband filter with passband $[0.8 ~~1]$ ( where $1$ corresponds to the ...
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Popping sound after using bandpass filter
I'm trying to create guitar Wah Wah effect (basically band pass filter with dynamic frequency range). I'm using Steinberg SDK for it. I refactored this code to work in real time and it looks like this:...
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Audio signal series' beginning points (about 50) distort after a bandpass filter
I am using some bandpass filters to detect a certain frequency of the sampled audio series in noisy environment. Everything is OK except this:
I found that for many bandpass filters I tried(...
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IQ modulation: baseband to bandpass transformation
Given is a baseband signal representation.
A : Complex Signal
R : Real Signal
If I multiply baseband signal with FT(cos) then the signal will look like first plot ...
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Apply FIR filters to Extract Stego from WAV data
I appreciate anyone that takes a moment to help me with this problem. I've been banging my head against the keyboard for a while, searching forums and DSP tutorials and I can't figure this problem out....
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LP to BP transformation steps
Considering the following problem, What i know to convert from LP signal to BP signal is to:
Draw the FD of the LP equation
From it I can draw the FD for BP
From this graph I can deduce the equation ...
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Python equivalent code for Matlab bandpass function
I have used a bandpass filter function in Matlab as follows
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How to combine highpass and lowpass filter to implement a bandpass filter
I want to implement a bandpass filter by using and combining my highpass and lowpass filter functions in Python:
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power spectrum of passband of ofdm is it right shape or not?
I tried to get power spectrum of ofdm passband signal.
Below is the whole matlab code for that with BPSK+ofdm.
and I got the power spectrum as below.
I wonder that is that right form or not?
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About the process to convert basedband signal into passband
Theoretically, the passband $y(t)$ signal equivalent into baseband signal $x(t)$ is given by:
$y(t) = \Re \begin{bmatrix}
x(t) e^{(-i2 \pi f_ct )}
\end{bmatrix}$
where $\Re$ represents the real part.
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How to generate wideband Gaussian white noise
I want to generate correlated complex white Gaussian noise signals in MATLAB. What I do is that I take complex Gaussian random variables with unit-variance and multiply them with the desired input ...
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How can to obtain the hughcut, lowcut and bode constant of a bandpass digital filter?
I need to create a bandpass filter amplifier in python; and determine the transfer function, graph the bode diagram, and print the highcut frequency, lowcut frequency, the bode constant and the ...
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How can to obtain the transfer function of a bandpass digital filter? [duplicate]
I've been asked to: create a bandpass filter amplifier in python, determine the transfer function, graph the bode diagram, and print the highcut frequency, lowcut frequency, the bode constant and the ...
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Reconstruction of sampled band-pass signal
I am pretty new to signal processing. I am currently trying to reconstruct a sampled band-pass signal created with the filtfilt and ...
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Theory behind the matlab butter function with the parameters n and [Wl, Wh]
I am writing the theoretical background in my thesis but my thesis is more centered on deep learning and the signals that I am using for classification were filtered through the ...
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About the variance of the coefficient of narrowband noise when using signal-space representation
Assume that n(t) is a white Gaussian noise process with zero-mean and power spectrum density $N_0/2$. By using the signal-space representation, it can be expressed as:
$$n(t) =\sum_{j=1}^N n_j \phi_j(...
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BPF Filtering with DSP IIR Realtime C++ filter library
I am working with complex samples, I have a main signal at 630KHz, my Fs is 1.26MHz and BW is 12.6KHz.
If I plot a frequency-magntitude spectrum it looks like this:
As you can see along with my main ...
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SOS-matrices' order does not correspond to given parameter when designing bandpass with scipy.signal.butter
I do not understand why this scipy operation:
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Find a band-pass filter
The question is: how can I define $h_1[n]$ in such a way that $h [ n ] = \delta [n - 1 ] + 2 \delta [n -2 ] + h_ 1 [n]$ is a band-pass filter. My thought was the following.
Firstable, I wrote the $Z$-...
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Basic question about Bandpass and lowpass filter using Python
I have a signal that is the sum of 3 signals that has just passed through a transmission channel. I need to put filters to this signal (bandpass and lowpass) and then apply demodulation and get one of ...
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Find the band pass signal for a given low pass range and cutoff frequency?
We know the fact that a bandpass signal is defined for real values. But for a typical scenario where we have a signal in the lowpass range:say : 𝑥𝐿(𝑡)=𝑗𝑋0 sinc(Bt) and the transformation of the ...
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Find the output signal in a Low Pass Filter for a given cutoff frequency range
I have a scenario where 𝑥(𝑡)=2⋅sin150𝜋t +sin250𝜋t and g(t)=𝑥(𝑡)sin250𝜋 . The signal g(t) is passed as input through an ideal lowpass filter with cutoff frequency(fc)= 300𝜋 and passband gain= 3....
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How to create a real bandpass filter?
I'm trying to create a real bandpass filter (17-point) in Python by calculating the coefficients b of a signal. This is the formula I'm using:
$$b = \cos(ω(k-k_m))$$
for $k = 0,1,..,L-1$, where $k_m$ ...
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implement bandpass filter on complex valued signal? (C++)
I want to filter out complex valued samples - Bandpass filter.
I have 100 complex samples and I wish to filter out a range of frequencies from it, as you can see in the result of the FFT, there are 3 ...
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Bandpass general equation to difference equation
I know this is a very basic question and I am coming out from a quarter of DSP. I want to create a function in Java which can taken in two parameters, either ...
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SineWave generation and BandPass filter : Audio
Can any one suggest me a Bandpass filter in java which I would like to apply on generated sine wave of a particular frequency
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Help with audio EQ cookbook BPF filters and Q
I am fairly new DSP, and am using maths that I have not used in 20-30 years. I have been working with Cookbook formulae for audio EQ biquad filter coefficients by Robert Bristow-Johnson and am having ...
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Python bandpass filter - singular matrix error
I've been trying to design a bandpass filter using scipy but I keep getting a LinAlg Singular Matrix error. I read that a singular matrix is one that is not invertable, but I'm not sure how that error ...
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Step response of bandpass fitler
I'm working on a virtual bass system and the signal flow is as follows
Where NLD denotes the nonlinear device which introduces both odd and even harmonics, and z^-D is to compensate the group delay ...
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Meaning of term in notch filter coefficient
I have a discrete implementation of a notch/bandstop filter that allows me to specify the stop band frequency, the width of the notch and the attenuation of the stop band frequency. I've been tasked ...
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How to get the difference equation from impulse response?
I'm trying to solve a problem about filter design.
We want to design a equalizer filter which have the following frequency response :
How can i get the difference equation from the impulse responce ...
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Derivation of the lowpass to bandpass transformation
I have a basic question.
The "well known" lowpass to bandpass transformation is
$$
s \longmapsto \frac{\bar{s}^2 + \omega_1\omega_2}{\bar{s}(\omega_1 - \omega_2)},
$$
which gives a bandpass ...
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Why use a notch filter to implement a bandpass
I have seen in a few papers, for instance in this one, the following method :
Find an initial "frequency of interest" (FOI)
Filter the input signal with a Notch filter around the FOI
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Passband filter with 0.3 to 0.9 Hz passband on signal filtered at 100 Hz
I have a signal sampled at 100 Hz with the frequency spectrum seen below.
What I would like to do is to filter out the region around 0.7 Hz (say 0.7 ± 0.3 Hz) (leftmost red circle) and get rid of ...
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How to properly band-pass filter an autocorrelated signal?
Let's consider an example ECG time series, sampled at 360Hz:
I verified that autocorrelating a signal preserves its frequency content. For instance, both original and autocorrelated data show the ...
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Narrowest passband dsp filter one can apply
I was wondering how one would know the narrowest pass-band digital filter one can apply, given the original signal's sampling frequency. For example on a signal coming out from a 14 bit ADC acquiring ...
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Paper replication: Validating the proper way to pass .wav audio breathing data through a bandpass filter
I am working on trying to apply a low and high pass filter to an audio file that contains a set of exhalations over a microphone. The inhalations have been cut out of the file, and the exhalations are ...
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FIR filtering returns "static" signal
//PROBLEM
I'm trying to filter EEG trials from an array in which each trail has dimensions [8x125] = [number of channels x samples@250Hz], but the resulting signal looks static and wrong. Why is this ...
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Is it possibel to use CNN to bandpass signal?
I have a time serie dataset and want to train a CNN-LSTM model to predict as well as detect outliers. How can I use CNN to filter the signal and extract features from specific frequency band?
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How to identify from poles and zeros if it is a bandpass
For an example, this is a figure I made from MATLAB, based on the poles and zeros, how can identify if it is a bandpass filter.
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Bandpass filter equivalent for amplitude
I have a signal where I am using a bandpass filter to limit the frequency range. I am also interested in filtering the remaining frequencies (after bandpass filtering) within the signal by their ...
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How Short-time Fourier transform (STFT) is different from from filtering?
If we want to know frequencies in a signal over time I know we can use Short-time Fourier transform (STFT). but I read in a paper "The spectrogram representation was obtained by first filtering ...
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Problem wih (diverging?) digital IIR filter for an online acquisition system
I am trying to plot windows of acquired data from an LSL-compatible system. For the example below, let's consider 1-second window of a 64 channel EEG system. In practice, I use shorter 0.2-window, but ...
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