## Scaled Sines into Chebyshev

Started by in comp.dsp7 years ago 5 replies

Hi all! Noob here! First time posting! I'm attempting to run a sine wave through a chebyshev polynomial in order to get a given spectrum. ...

Hi all! Noob here! First time posting! I'm attempting to run a sine wave through a chebyshev polynomial in order to get a given spectrum. I can provide code but unfortunately it's in Java inside Max. I have it working *I think* but I have one thing I'm trying to wrap my brain around: DC My impression (Although I very well could be wrong) is that chebyshev polynomials a

## Chebyshev IIR - how to achieve band-pass tranform?

Started by in comp.dsp14 years ago 7 replies

Hello newsgroup, the book "Guide to Signal Processing" shows a recursive filter, the chebyshev filter, implemented either as LowPass or as...

Hello newsgroup, the book "Guide to Signal Processing" shows a recursive filter, the chebyshev filter, implemented either as LowPass or as HighPass version. How can you use a Chebyshev in a singel stage as a BandPass filter? A BandPass implemented as FIR is formed by adding the Low- and HighPass filter kernel. So, is it possible to perform such an action with Chebyshev as well (e.g...

## polynomial approximation

Started by in comp.dsp13 years ago 4 replies

Hi This is regarding usage of chebyshev polynomials for function approximation. I work on this problem during my spare time. The Chebyshev...

Hi This is regarding usage of chebyshev polynomials for function approximation. I work on this problem during my spare time. The Chebyshev polynomial coefficients are obtained from unequally spaced zeroes of the function. But, if we use the same Chebyshev polynomial to approximate a periodic finction, is there a certain way to model (a mathematical equation) the error involved, assuming ...

## Chebyshev Part II: Factorization!

Started by in comp.dsp7 years ago 9 replies

Hey all, you were so helpful last time that I thought you might help again in my efforts to create a chebyshev distortion. It looks like I've...

Hey all, you were so helpful last time that I thought you might help again in my efforts to create a chebyshev distortion. It looks like I've got all my math right. But unfortunately it looks like I need something like 40 to 60 harmonics to really do this right This is not CPU friendly AT ALL! BAD NEWS! I've even written code to collect the terms into a simplified version like

## DCT derivative

Started by in comp.dsp11 years ago 9 replies

Hi all, I am trying to calculate derivatives of chebyshev coefficients using FFTW for cosine(x). However I am not getting back the right values...

Hi all, I am trying to calculate derivatives of chebyshev coefficients using FFTW for cosine(x). However I am not getting back the right values when I perform inverse chebyshev transform. Can anyone check the code below and tell me the possible errors. Thank you. program test implicit none #include "fftw3.f" INTEGER, PARAMETER :: N=4 INTEGER(8) :: plan ...

## 2nd order Chebyshev II analogue prototype

Started by in comp.dsp15 years ago 5 replies

Hi all, I need the above, but I can't find it in any of the books I have handy and every google search I try turns up nothing but...

Hi all, I need the above, but I can't find it in any of the books I have handy and every google search I try turns up nothing but references to Matlab :-(. The Chebyshev I analogue prototype is: H(s) = 1 / (s^2 + s / Q + 1) and I was thinking of subtracting the above from 1 but I'm not sure that's correct. Anyone have a book handy? TIA, Erik -- +-----------------------...

## Gain in IIR Chebyshev Filter?

Started by in comp.dsp11 years ago 10 replies

Hi everyone!! I have a problem when I calculate the coeffs of my chebyshev IIR filters (via Bilineal Transformation), and I hope someone can help...

Hi everyone!! I have a problem when I calculate the coeffs of my chebyshev IIR filters (via Bilineal Transformation), and I hope someone can help me! The thing is that when I compare my coeffs with other filter design softwares, the denominator coeffs are correct but the numerator ones I get are multiplied by a gain. That is: For LP, e.g. order 1, and H(z) = (A + Az^-1)/(1 + Bz^-1) --> (A+A)/

## IIR BandPass nominator

Started by in comp.dsp9 years ago 7 replies

Hello 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...

## IIR vs. FIR (complexity issues)

Started by in comp.dsp13 years ago 2 replies

Hi, I would like to know on the implementation complexity issues beween FIR Filter vs. IIR Filter (Chebyshev). I know that IIR is more...

Hi, I would like to know on the implementation complexity issues beween FIR Filter vs. IIR Filter (Chebyshev). I know that IIR is more complex than FIR. But, in case of the FIR filter has higher order number than IIR, FIR can be more complex. If I have IIR Chebyshev 10th order vs. FIR with 59 Taps. Which one is the most complex one? Thanks, Berry

## Digital filter design software for Android phones

Started by in comp.dsp8 years ago

I have just created an Android app for designing digital filters. You can design Butterworth, Chebyshev, 2nd Order Shelf, 2nd Order Parametric,...

I have just created an Android app for designing digital filters. You can design Butterworth, Chebyshev, 2nd Order Shelf, 2nd Order Parametric, DC Blocker, First-Order Lag, Exponential Averaging filters and IEC 61672-1 A-Weighting & C-Weighting filters (Class 1) with this app. The Butterworth and Chebyshev filters can be any order of your choosing. The app will calculate the filter

## How to calculate Chebyshev coefficients

Started by in comp.dsp14 years ago 7 replies

Hello, I'm stuck on how to calculate the Chebyshev's transfer function's coefficients. The notes I'm following determine the coefficients...

Hello, I'm stuck on how to calculate the Chebyshev's transfer function's coefficients. The notes I'm following determine the coefficients once epsilon is calculated. The following equation yields epsilon: epsilon ^ 2 = 10 ^ (r / 10) - 1 Using the equation above, for r = 1dB, epsilon = 0.5088 The transfer function is defined as: H(s) = k' / ( a_0 + (a_1 * s) + (a_2 * s ^ 2) + (a_...

## Testing a chebyshev filter

Started by in comp.dsp15 years ago 7 replies

I'm not quite sure what I'm expecting as an output! I seem to be getting a square wave from a sine wave with an continually decreasing...

I'm not quite sure what I'm expecting as an output! I seem to be getting a square wave from a sine wave with an continually decreasing frequency! Is this right? Cheers Triff

## paper needed

Started by in comp.dsp14 years ago 1 reply

Complex Chebyshev Approximation for FIR Digital Filter Design Lina J. Karam & James H. McClellan if any bidy has this paper please email...

Complex Chebyshev Approximation for FIR Digital Filter Design Lina J. Karam & James H. McClellan if any bidy has this paper please email it at danishzzz@yahoo.com thank u

## Bandpass filter techniques

Started by in comp.dsp15 years ago 11 replies

Some bandpass filters I have heard of: 1. Chebyshev 2. Butterworth 3. Raised Cosine What are the attribtues of theses filters that make...

Some bandpass filters I have heard of: 1. Chebyshev 2. Butterworth 3. Raised Cosine What are the attribtues of theses filters that make ones more useful than another in a given sitation? Iasac

## Noise-feedback...

Started by in comp.dsp15 years ago 1 reply

Hi group! I'm an engineering student and I'm trying to implement an IIR filter. It's a 6th order Chebyshev LP filter. We perform L2 norm...

Hi group! I'm an engineering student and I'm trying to implement an IIR filter. It's a 6th order Chebyshev LP filter. We perform L2 norm scaling of the coefficients. To simulate the implementation environment we programmed the whole thing in Matlab, rounding the products in the appropriate places. Everything works fine, but as the final task in this assignment we are supposed to ...

Started by in comp.dsp13 years ago 2 replies

hi, This is my first filter implementation and is made in Scilab, also the design of the 3ord Chebyshev Type I IIR Filter (with the iir...

hi, This is my first filter implementation and is made in Scilab, also the design of the 3ord Chebyshev Type I IIR Filter (with the iir function). I actually have 3 filters, so i can use them as an equalizer for an audio application. I´m using Direct Form I Realization. Since I have to implement this on a 24bit Fixed-Point DSP I had to scale my coefficients by a factor of 256 (same as shifting...

## Clarification of Rivlin-Shapiro theorem for FIR filters

Started by in comp.dsp15 years ago 4 replies

Hi, I have problems applying Rivlin Shapiro's theorem for design of FIR filters. It says in [1] that : H(z) is best Chebyshev...

Hi, I have problems applying Rivlin Shapiro's theorem for design of FIR filters. It says in [1] that : H(z) is best Chebyshev approximation to D(z) if and only if there are r points z1,z2,....zr and r positive numbers lambda1, lambda2, ... lambdas sum to 1 ... for which : sum(k=1 to r) lambdak [D(zk)-H(zk)] fi(zk) = 0 for i=1,2,....,N ..... Main question is what are functio...

## Faster fft on P4 + winxp?

Started by in comp.dsp14 years ago 2 replies

Hello, I am using fftw in a fluid simulation code for doing 1D,2D ffts and cosine transforms associaciated with Chebyshev...

Hello, I am using fftw in a fluid simulation code for doing 1D,2D ffts and cosine transforms associaciated with Chebyshev differentiation. All this is done on a P4 pc with winxp. Code written in C on the dev-C++ IDE i.e. the compiler is gcc. To my surprise, it turns out that the simulation run times are dominated by the ffts (I expected the matrix inversion in the elliptical p...

## Standard filters for interpolation/decimation?

Started by in comp.dsp16 years ago 2 replies

I'd really like not to reinvent the wheel for my current hobby project, so I beg of all DSP people out there - what are the standard filters...

I'd really like not to reinvent the wheel for my current hobby project, so I beg of all DSP people out there - what are the standard filters used for 16X interpolation/decimation? Are they windowed-sinc, Chebyshev, Butterworth, or something else? And what are the coefficients, can I find tables of them somewhere? My goal is to create a simple VST guitar distortion plugin which uses non-lin...

## What am I missing about IIR Filter Design?

Started by in comp.dsp6 years ago 11 replies

Every article I see regarding IIR filter design seems to make the subject far more complicated than it needs to be. For example, in this...

Every article I see regarding IIR filter design seems to make the subject far more complicated than it needs to be. For example, in this DSPRelated post "IIR Coefficient Calculation - ger_lough" the discussion goes on in great length about specific formulas for different protoypes (Butterworth, Chebyshev, etc) sampling rates, Q, pole locations, etc. I wrote an IIR Filter design program wher...