## Forums Search for: Bessel

## Higher order Bessel filter

inCan anybody give me an idea on how to implement nth order bessel filter with cascaded biquad sections? I am able to implement higher order...

Can anybody give me an idea on how to implement nth order bessel filter with cascaded biquad sections? I am able to implement higher order Butterworth with cascaded biquads by following equations given in the link http://www.musicdsp.org/files/Audio-EQ-Cookbook.txt I found that to design filter coefficients for the biquads, Q has to be changed in the equation Alpha = alpha = sin(w0...

## KB-Window

inWhat is the identity (formula) of a Kaiser-Bessel window. I need something like W[n] = F(n,alpha)= .........?

What is the identity (formula) of a Kaiser-Bessel window. I need something like W[n] = F(n,alpha)= .........?

## Anti-Aliasing filter

inIf you are estimating time-delay bewteen two microphones would it be better to use a Bessel filter for anti-aliasing rather than a Butterworth...

If you are estimating time-delay bewteen two microphones would it be better to use a Bessel filter for anti-aliasing rather than a Butterworth due to the approximate linear phase. Wang King

## bartlet

inhi folks, i have a term project about high-pass bessel filter with fstop = 200Hz and fPass = 400Hz, there's no big deal in "iir" design, i...

hi folks, i have a term project about high-pass bessel filter with fstop = 200Hz and fPass = 400Hz, there's no big deal in "iir" design, i could overcome it, but at the "fir" design i was asked to perform this by a "bartlett window" and my brain is almost to explode, i can't find any articles, any techniques and unfortunately there's no assistants to help me (and as we all know "if you don't know ...

## how to get rid of ringing with IIR notch filters?

inHello, I have an IIR notch filter ( i.e. bandstop ), that rings like crazy whenever a transient signal comes through ... which is very...

Hello, I have an IIR notch filter ( i.e. bandstop ), that rings like crazy whenever a transient signal comes through ... which is very unwanted for my application. Anybody have any ideas how to get around this? I have to stick with IIR form filters. I've tried all the various standard design flavors, i.e. Butterworth, Bessel, Elliptic, etc ... but they all seem to ring unacceptably abou...

## newbie filter question

inHi everyone, Just got handed a 600000 line software application with lots of DSP. I am trying to understand a few things and as I am new to...

Hi everyone, Just got handed a 600000 line software application with lots of DSP. I am trying to understand a few things and as I am new to DSP, it is a bit complicated. Here is a scenario. There is a signal that is being fed into a cascaded Bessel filter bank that splits it into 0-60 Hz, 60-120 Hz, 120-180 Hz, 180-240 Hz uptil 480 Hz... i.e. in bands of 60 Hz. After this, the output ...

## Help on cascaded filter freq correction

inI've figured out the cutoff frequency correction factor necessary to force a 2-pole Bessel lowpass filter to exhibit 3 dB of power attenuation...

I've figured out the cutoff frequency correction factor necessary to force a 2-pole Bessel lowpass filter to exhibit 3 dB of power attenuation at the cutoff frequency I specify, for a single pass of the filter. The problem is, if I stack up multiple passes, I can't seem to get it right. Here's what I've done so far. Filter response function H = W^2 / (W^2 + 3W + 3) [1] This w...

## pdf of product of two dependent rv

inHello, I am facing problem in finding the pdf of Z= AB+CD, where A, B, C, D are independent normal random variables with...

Hello, I am facing problem in finding the pdf of Z= AB+CD, where A, B, C, D are independent normal random variables with zero mean and uneqaul variances. I could bale to find out the pdf's of each term (i.e. AB or CD). It is a well known result that AB has a pdf of modified Bessel function of the second kind. If we add two random variables having the pdf of " modified...

## Cascade Form IIR Filters

inhi! All, i would like some info on implementing cascade form IIR filters...does matlab support it???...as far as i can understand...

hi! All, i would like some info on implementing cascade form IIR filters...does matlab support it???...as far as i can understand butter,cheby1,cheby2,bessel,ellip generate coefficients in the direct form...how do i implement the cascade form... TIA bngguy

## filtering of noise signal

inhow to filter a noise signal using iir filter coefficients-- cybyshev or bessel, band is between 45hz to 65hz, sampling frequency 1000hz if...

how to filter a noise signal using iir filter coefficients-- cybyshev or bessel, band is between 45hz to 65hz, sampling frequency 1000hz if 240 hz pure signal noise +signal =270 hz----> iir filter-----> 240hz

## Modulation transfer function

Hi, I have a doubt regarding 1 other project. I have to get the modulation transfer function of an image (and the same image defocused)....

Hi, I have a doubt regarding 1 other project. I have to get the modulation transfer function of an image (and the same image defocused). The defocus is either induced by constructing a bessel filter (similar to airy functions, defocus created by unfocused thin lens). Even though I already designed the filter, I am currently using a webcam to get the defocus by altering the focus of the le...

## IIR BandPass nominator

inHello everybody, I have problem with nominator of H(z) of bandpass filter. I develop musical open-source software (non-commercional) and I...

Hello everybody, I have problem with nominator of H(z) of bandpass filter. I develop musical open-source software (non-commercional) and I wrote my filter-design algorithms based on polynomials (without complex aritmetic). I have all working well (Bessel, Butterworth, Chebyshev, inverse Chebyshev and Cauer's elliptic filters Low, High Band pass and band Reject). Now I decided do rewrite my al...

## Digital filter woes

inI'm trying to design an LP IIR digital filter but not having much luck. The bandwidth of my filter is too low. The filter specifications are:...

I'm trying to design an LP IIR digital filter but not having much luck. The bandwidth of my filter is too low. The filter specifications are: pass, stop and sampling frequencies 4.8, 8.5 and 30 KHz respectively; maximum pass band ripple 0.5 dB and minimum stop band attenuation 30 dB; filter type Bessel. I obtained the poles and zeros with the Python Scipy function iirdesign. There are seven p...

## FIR all pass and Bessel Function unit sample response

inOnce upon a time I wrote a nonlinear program to compute the unit sample response (i.e. to "design") FIR filters with the following...

Once upon a time I wrote a nonlinear program to compute the unit sample response (i.e. to "design") FIR filters with the following characteristics: 1) Minimax solution to all pass. 2) The unit sample response could not be the trivial single unit sample - rather, it had to have: a) "length" b) the samples had to be in a magnitude range something like from 1 to 2.5 with arbitrary s...

## THD digital FM demod

inHi, I have designed a digital FM demodulator... I have a 70 MHz FI signal that I downconvert to baseband This demodulator works fine with...

Hi, I have designed a digital FM demodulator... I have a 70 MHz FI signal that I downconvert to baseband This demodulator works fine with Analog Bessel 24 order filter on I and Q signals before demodulating. When I change this filter with a digital FIR filter (phase lineartity) I have a -50 dB THD My message signal is a pure 10 MHz filter sine My -50 dB THD is due to a 20 Hz sine...

## Frequency Modulation Spectra

inThe frequency spectrum of an FM signal with a sinusoidal modulating signal is a discrete infinite frequency series where the carrier and...

The frequency spectrum of an FM signal with a sinusoidal modulating signal is a discrete infinite frequency series where the carrier and sidebands are given by the Bessel functions, which are themselves a function of the modulation index. But when the FM signal is modulated by TWO sinusoidal signals, is the spectrum represented by TWO infinite frequency series? Or is the spectrum mo...

## phase error variance to rms phase error

inhello, i have an expression that gives the phase error variance of QPSK system as follows:\ phase error...

hello, i have an expression that gives the phase error variance of QPSK system as follows:\ phase error variance=(Aif/sqrt(2*pi*n))*I0(-Aif/2*n) here, Aif=IF amplitude, n=noise component variance, I0=modified bessel function of the 1st kind How can i calculate rms phase error of that system from this phase error variance thanks