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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FFT Filter design
How to create an FFT filter (lets say, a band-pass) as been asked here before (e.g. Running an FFT filter on a large data set) but (I guess) given the questioner inexperience in digital filter design ...
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Problem understanding the actual bandpass of my EEG signal
Greetings to all of the community members.
I am a clinical neurologist and in the last few weeks I am beginning to study EEG spectral analysis.
My unit uses CADWELL Essential 32 channels amplifier for ...
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"There should be at least a factor of four between sample rate and upper edge of passband"
Publishing a paper within biomedical engineering, specifically concerning time series data, we have gotten into a disagreement with a reviewer. Specifically, the reviewer says that "the upper ...
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The moving of the poles and zeroes during the low-pass tranform
Usually, we start the design of a filter using a low-pass prototype. Then we transform it to the required high-pass, band-pass or band-stop form as required. I'm looking for a good explanation on how ...
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What is the relationship between sound frequency that generated by fan and the RPM of fan itself?
So I just bought high RPM external fan for laptop. It doesn't have sensor. So it's purely actuator device. Therefore the cheap measurement I can do, is using my phone microphone and open spectrogram ...
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How can I calculate how much of my signal at the beginning and end will be affected by the filtering process?
I'm using a Butterworth bandpass filter to process my signal (low-pass + high-pass, I am also applying a notch filter). I would like to calculate how much of my signal at the edges will be affected by ...
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Butterworth Bandpass Filter Design
Determine the transfer function for the Butterworth bandpass filter? (At the Transfer Function Factoring and Sp Substitution stage)
The Parameter
$$a_{pass} = - 1dB$$
$$a_{stop} = - 20dB$$
$$f_{pass1} ...
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How can I smoothen this Chebyshev type I bandpass filtered signal?
I'm unable to figure out the cause behind my noisy bandpass filtered signal, despite my adaptation of the paper's parameters, in which they specified it to be a 4th order Chebyshev type I bandpass ...
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What duration of a white noise burst is required for it to be "white" at a given frequency or frequency range?
I am running white noise bursts (with very short ramps on/off to prevent discontinuities) through underdamped resonant bandpasses which are tuned to any given $f_0$ and an underdamped $Q$.
Continuous ...
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What is the cleanest, most transparent way to rapidly excite a resonant bandpass to a given amplitude (for musical synthesis)?
Background
Music audio synthesis can be performed using underdamped resonant bandpasses as harmonic oscillators (set to harmonic frequencies of a given note). These can then be excited when input ...
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PSD of real and imaginary parts of complex envelope of a bandpass signal
I know that we can write a real bandpass signal x(t) as:
$x(t)=x_c(t)\cos\omega_ct + x_s(t)\sin\omega_ct$
$x_c(t) = 2x(t)\cos\omega_ct$ for $|f|<W$
$x_s(t) = 2x(t)\sin\omega_ct$ for ...
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Confusion on when a filter is considered band-pass
As part of an assignment, I was given a filter with a specific set of poles and zeros, namely poles at $0.51 \pm 0.68i$ and zeroes at $1.5$ and $−0.7$. This part of the assignment is titled as "...
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Is a bandpass filter superfluous when the frequency band of interest after applying the FFT is below the Nyquist frequency?
I have time-series data with a sampling rate of 1 Hz, hence the Nyquist frequency is 0.5 Hz.
I am interested in the frequency band 0.01-0.1 Hz and I would like to apply a Periodogram to transform the ...
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Use periods instead of frequencies in Comodulograms
I want to create a Comodulogram to assess PAC. I use the pactools library, which uses frequencies. Since I work with hourly data and want to look at multidien phases, it would be better to use periods ...
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Is there any way of calculating the portion of signal lost as we keep on reducing the passband edge frequency of a band-pass filter?
Any kind of references would be appreciable.
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Calculating the settling time of lowpass and bandpass SOS filters constructured using SciPy
I have constructed a high pass filter using scipy:
...
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Understanding the parameters of a notch filter
Adobe Audition has a very interesting notch filter that have been very useful to me. It has the following parameters
According to their documentation, the chosen frequency is the center frequency and ...
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Given two low-pass digital IIR filters, find bandpass coefficients
In the case of FIR filters it is easy to get a band-pass filter by subtracting the coefficients of two low-pass filter filters or by convolving a high-pass and a low-pass filter:
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Reduce memory usage by bandpassing a signal
When recording an audio signal one can have a high sampling frequency. To reduce the amount of data that is stored, and thereby the power consumption, I head that it is possible to use a high-pass ...
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Can the standard deviation of the Gaussian window in a Gabor filter be made infinitesimally small?
My understanding is that the standard deviation of the Gaussian window in a Gabor filter dictates the temporal resolution.
Wouldn't it always be better then to make the window smaller, thus achieving ...
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What is the difference between STFT and Gabor filter?
My understanding is that a Gabor filter gives us information about when in the input signal does the frequency of interest (equal to the frequency of the sinusoid in the Gabor Filter) occur, thus ...
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How to band pass only on positive frequency [duplicate]
I've posed the similiar question
I appreciate that the former replier tells me the process is about Hilber transform,but I'm still confused with the positive frequency.
The paper process a cardiac ...
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fast fourier transform band pass filter only on positive frequency
Recently, I came across a paper that focuses on signal processing using lock-in amplification.
the algorithm involves applying the Fast Fourier Transform (FFT) to a time-domain biosignal.
A band-pass ...
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What does a Gabor filter "filter" out?
Almost all of the searches online have returned results related to image-processing, but I am looking for a more rudimentary example with some physical intuition (eg; a high-pass filter only lets the ...
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single tone -> multi bandpass filter -> incorrect output
background:
Trying to filter out all other signal frequencies except -> signal whose frequency can be in multiple's of 16Hz {16,32,48.......160].
so started experimenting with a single tone [no ...
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Issues with ML Pattern Recognition After Bandpass Filtering
We've been working on a machine learning project for pattern recognition, using time-domain features such as kurtosis, mean, standard deviation, variance, skewness, and peak-to-peak values.
Background:...
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How can I simulate the process of transmitting BPSK signal from start to end?
I would like to simulate the process of transmitting a binary phase shift keying (BPSK) signal from start to finish, going through each step over additive white Gaussian noise (AWGN) channel. I know ...
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Event-related EEG (epoch averaging) as a form of inter-harmonic bandstop filtering?
There is a matter that comes to my mind from time to time, now I describe it in detail.
Anyway I am a first year PhD student, doing research in the field of cognitive neuroscience, but yet I only have ...
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How to construct a bandpass filter with minimal loss in amplitude/power near the lower and upper frequency limit in Python?
I am analyzing functional MRI data with a sampling rate of 1 second (1 Hz). The frequency band that I am interested in is 0.01-0.2 Hz.
Regarding measurements, I am interested in computing (1) the ...
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Hilbert transform with non-modulated signals
Is it correct to compute the Hilbert Transform and then the complex envelope, expressed as $v = z~ e^{-j 2\pi f_c t}$, where $z$ represents the analytic signal and $f_c$ represents the carrier ...
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Fitting high order rational function to frequency response measurement data
I need to model measurement data of a frequency response with physically meaningful band-pass filters.
All Measurements happening in die range of 20Hz to 20000Hz
I have to work with python.
The ...
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Narrow bandpass filtering
I want to plot a specific frequency (e.g., 1 kHz or 100 Hz) of an audio file (sampling rate 44.1 kHz). I have done fft and spectrogram analysis on the file, but I am now interested in plotting only ...
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Maximum bandwidth of radio-frequency filter to avoid the image frequency
Consider the following super-heterodyne receiver
The carrier frequency of the local oscillator is chosen to be
$$ f_{LO} = f_c + f_{IF} \tag{1} $$
where $f_c$ is the transmitted carrier frequency and ...
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Bandpass filter with a changing passband
The problem:
I have a signal that contains multiple, relatively stable frequency components and I want to extract only one of them. I attached a plot that illustrates the situation with a simple ...
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Proof of the equivalence of the Band-RMS evaluated in time and frequency
Ignoring normalization factors, we can define the squared Root Mean Square (RMS) of a discret-time signal $x[t+n], n=0,1,...$, at time $t$ as:
$$\mathrm{RMS}^2_t = \sum_{n=0} ^{N-1} |x[t+n]|^2$$
...
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Calculating the filter coefficients for 2nd order bandpass and bandstop Butterworth filter
I want to calculate the filter coefficients for both bandpass and bandstop filter for 2nd order Butterworth filter, like
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Bandpass filtering EEG and getting weird distortions, parameter issue?
I am trying to bandpass filter an EEG signal, nothing fancy but it's coming out pretty distorted.
EEG data is taken from forehead. Sampling rate is 250 Hz. Cutoff is 2.5 Hz & 120 Hz.
Tried in both ...
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design of cascaded biquad filter
I have to compare the response of an 8th order IIR filter and its equivalent 4 stage cascaded biquad structure. A sinusoidal signal is given as input to both the systems and the output responses are ...
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Bandpass function in Matlab inverting the Frequency spectrum when using a hermitic transformed signal
I have a VNA response (S11 parameters) from 3.5 to 40 GHz. Then I apply a hermitic transformation (complex conjugate) to it since we only have the spectrum for the positive frequencies. Then I use ...
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Matlab: How to implement a bandpass filter to isolate harmonic with 0 gain at this frequency? [closed]
I want to isolate the harmonic at 440Hz and I need to design a filter with zero gain at 440Hz.
I tried this with matlab:
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Filter IIR, 1/3 Octave Corner with 2 Octave BW
I'm trying to design a new filter with IIR to filter out specific bands.
Basically it's a bandpass filter with 2 Octave or 3 Octave bandwidth but the filter order should be equal to 1/3 Octave filter.
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Inverting (spectrogram vertical flip) a signal of WAV file
What I need is to invert a signal (on spectrogram it would look like a vertical flip) of a WAV file. Actually, of a bandpass of a signal - from 500 to 800 Hz, for example.
This image will perfectly ...
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frequency Domain with bandlimit
May I ask why does the frequency Domain Picture of a signal look like that? Is the signal built with many different frequencies?
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Practical problems in down-converting via Hilbert filter
While teaching communication system to my students, I showed different ways to define the diagram block of the system responsible for transforming a bandpass signal, $x(t) \in \mathbb{R}$, into its ...
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Bandpass Stationary Stochastic Process
I was following this interesting post by a new user Rubem Pacelli and got stuck at Proakis' referenced definition (see Section 4-1-4 starting on page 159 here). The math, all repeated further below, ...
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Designing a digital band pass filter with Sinc filter in time domain
I want to design a sinc filter in the time domain (a bandpass filter in the frequency domain).
I wrote test code in python to investigate, and would appreciate help understanding it and answer my ...
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Signal power after frequency shift with different frequency than the carrier frequency
I have this received signal in passband
$$
\begin{split}
r(t)=&\Re\left\{\tilde{x}_1(t)e^{j2\pi f_1t}+\tilde{x}_2(t)e^{j2\pi f_2t}\right\}\\
=&\Re\left\{e^{j2\pi f_1t}\underbrace{\left[\tilde{...
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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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