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Polyphase FIR interpolation filter

Hello! Im looking for a simple matlab code that illustrates an interpolation using polyphase implementation. I need this to understand the purpose with the polyphase structure. Maybe anyone knows some sources also? Thanks in advance ...

Questions regarding polyphase filter

I am try to get a better understand of polyphae filter. There are several questions I wonder if I can get some help: 1) Relationship of polyphase filter and Different signal interpolation/decimation methods. One thing I am a bit confused about is the relationship between different curve fitting t...

polyphase filtering

hi.. This is my 1st mail to this group. I am trying to do a polyphase filter bank in dsp and thn get it into FPGA.. this is not for decimation or interpolation. This is mainly done for radio telescope back end in which we need 4 or 8 small channels from a big IF coming in. Can any one help me t...

Polyphase filter questions

Hi, Hoping some of you experts can shine some light on the following regarding polyphase filtering 1...I created a polyphase FIR interpolator, sampling frequency is upsampled by 10 from 10KHz to 100KHz. It works fine and I get the required frequencies output on the scope. I notice however, ...

Polyphase FFT Filter bank

Hi, I would appreciate if someone could help me by advising me on the implementation of a polyphase FFT filter bank on a FPGA. I understand the basic fundamentals & computationally-efficient/improved side-lobe rejection advantages of polyphase fft filter banks. My implementation is based on a p...

Re: Polyphase decimation filter, is it only a mathematical gimmick?

Yes. The polyphase technique is a way of achieving the same output with a reduced number of arithmetic operations. ...

polyphase channelizer

hi all, I'm trying to build a polyphase channelizer in matlab using a prototype filter(sqrt nyquist) as my school project. Can anyone please explain this concept more precisely to me and what are the important things I should consider when implementing. Thank You. Riddhi ...

Regarding polyphase IIR filter.

Dear All, Iam working subband acoustic echo cancellation.In that for subbanding the input signal i used polyphase IIR filter.I searched in net for polyphase IIr filter design.I got some techinical documents related to polyphase IIr filter, I mentioned important links related to do...

High pass polyphase filter

Hi all, I'm trying to design an high pass polyphase filter. The approach is to take the 5 tap high pass FIR, oversample it by a factor N (usually 128 or 256), then subsample it again into the different phases. The oversampling was done by polynomial interpolation and by zero-padding and ...

polyphase filterbank

Does any have an efficient implementation of polyphase filterbank in C? M=32 thanks Andrew ...

regarding polyphase IIR filter.

Dear All, This is the my first mail to post our group.Iam working on subband acoustic echo cancellation.In that for subbanding the input signal 2 path polyphase IIR filter is used.I searched for polyphase IIR filter design in net I got some techginical documents.In those documents one doc...

Group Delay of Polyphase FIR filters

Could anyone explain or point me to any literature that explains how to compute the group delays of polyphase FIR filters used for decimation and interpolation? For example if an FIR filter with (N*L) coefficients is implemented as L polyphase filters each with N coefficients, what is the grou...

Polyphase FFT

I have a few programs that compute and display a running waterfall of an audio signal input to the PC sound card. The waterfall is computed via ordinary FFTs up to 1048576 points for the highest resolution settings. Recently I have seen a similar program that uses polyphase FFTs and it has a sp...

Polyphase FIR implementation

Hi, does anyone know if there is any reference code which implements a generic polyphase FIR resampler (up/down scaler), using Altivec instruction set? I searched the web (as usual), but I could not find anything really usefull, actully I did not find anything at all. Also non-obvious se...

Fractional decimation

Hello, I've been studying polyphase decomposition, decimation, interpolation and fractional decimation. I think I have a handle on what I'm doing, but there's one thing I don't understand... Do you have to have greater than an L*Mth order filter in order to use polyphase decomposition to put t...

Polyphase Filterbanks for Symbol Timing Synchronization

Hi, I am currently reading fred harris' papers mentioned below to implement a timing synchronization in my software DSSS receiver. A. Loop Control Architectures for Symbol Timing Synchronization in Sampled Data Receivers B. Polyphase Fitlerbanks for Symbol Timing Synchronization in Sampled Data...

Polyphase resampler jitter?

I've got a polyphase resampler that I've built, and I'm noticing a lot of jitter in the output power spectrum that I'm having a hard time tracking down. First a little about the resampler: It's designed so that the user provides an input signal, up/down values and a filter response, the program th...

Fractional Resampling WCDMA gives noise

Dear all, I will be grateful if I can get some light on this. I have Tx Data upsampled from 3.84MHz to 12 MHz (@3.125X. On the Tx side I use a nice RRC filter to perform interpolation and upsample using Matlab inbuild polyphase filter to generate Test vectors. Problem is , on the receive...

clocks used in polyphase interpolation scheme

Greetings, I am trying to understand how the clock domains work during interpolation using the polyphase structure. Does one use 2 different clocks during implementation(lets say an interpolate by 2 FIR filter). One at the input and one at the output which is 2x the input clock. IS th...

Polyphase interpolation on an image with real value only

Hi all, I encounter some "problem" while using polyphase filter for interpolation. I have implemented a 8 zero crossing with upsampling of L=32. The image I used are a simulated image with 4 sinc impulse response near the four corner. All pixels values are positive. While performing ...

Re: Where can I find comparision between symmetric and asymmetric TAP FIR filters?

clay@claysturner.com wrote: > On Dec 10, 1:53 pm, Rune Allnor wrote: > > On 10 Des, 19:41, vijay wrote: > > > > > Newbie Here. > > > > > I have been told that and we normally go for 3,5,7,9 Tap poly phase > > > filters for image processing.... and 4,6,8 Tap filters should not be ...

Scaling of fir polyphase filters

In a FIR filter the scaling of the input in order to avoid overflow at the output can be specified by using the 1st norm of the vector of coefficients. ymax=xmax*scaling*norm_1 for xmax=ymax=1 scaling=1/norm_1 How to use this relation in a multistage interpolator with polyphase decomposition...

VHDL source code for polyphase filter

Hello, Where can I find the VHDL ( or verilog) source code for polyphase filter? Is there any free implementation around? Regards ...

why do we need Polyphase decimatation filter?

I did a decimator FIR filter simply by doing the convolution only once every M' input sample. for example M=3: feed x0,feed x1, feed x2, convolution, feed x3,feed x4, feed x5, convolution, feed x6,.... Then I find many people talk about polyphase decimation filter, I wonder if it is more effi...

Polyphase Filter

Hi , I am designing a polyphase filter in HW, which will do a sample rate upconversion by a factor of 1.25 on the incoming data.It is implemented as a upsampling by 5 followed by a decimation(polyphase)by 4(5/4=1.25)...For this design let's say I have a clock rate of 100kHz then I am not sure w...

Re: Sample rate conversion, Multistage and polyphase?

On Oct 20, 4:59=A0pm, "baeksan" wrote: > Hi, > > I'm working on a audio sample rate converter. =A0I'm interested particula= rly > in the conversion from 44.1 to 48kHz. =A0I have a version that works usin= g > polyphase decomposition for a huge fir filter to convert from 44.1 to 48. >...

Re: Interpolation with FIR filters

in article 1132685207.779486.257470@o13g2000cwo.googlegroups.com, Anshu at anshu.dhawan@gmail.com wrote on 11/22/2005 13:46: > Can anyone please explain me about Interpolation using FIR filters? I > dont understand how they can be used for interpolation. might you understand how an FIR fil...

How to interpret polyphase coefficients generated in MATLAB

Hello everyone, I am trying to design a low pass decimator filter in MATLAB. I am supposed to decimate a signal sampled at 200MHz down to 10MHz. The signal bandwidth is 8 MHz and the signal spectra is centred at the sampling frequency. I began with the following code: ---------------------...

Re: Polyphase decimation

Praveen wrote: > Hi > > I am implementing a polyphase decimation of a 8k signal by a factor of > 20. I have designed a filter of pi/20, which means there are 20 > subbands. In case of decimation, the input gets shifted by a sample at > each time instant and then convolved with all the...

Polyphase Filtering Question

Im have a few question about polyphase filtering. Lets say you have a downsampling application. and in general with polyphase filtiering yoou wish to exploit the efficiency assocationw it downsampling before invoking the lowpass filter. If you didnt do ployphase filtering, lets say you implim...

Re: multirate filter design

jon8spam@yahoo.com wrote: > Hi, > When one designs a fractional rate change filter, when specifying > the filter parameters do you design the filter at the interpolated > rate or the decimated rate? > > For example if you have an input rate of Fs then interp by 64 > decimate by 12...

best method for implementing an SRC

Hi, i would like to know which is the best method for implementing a integer sample rate converter (decimation /interpolation) in terms of quality. the conversion rates required are (2,4,8,16) both decimation and interpolation.i had tried with polyphase implementation and lagrange interpolatio...

FMDemod, Phase noise and Polyphase

Hi All, I am trying to debug a FM demodulation noise problem for a FPGA prototype. The output in general looks ok, but the THD+N of a clean 60% modulated signal is only in the mid-40's dB (noticable even by ear), and that is mainly due to a high noise floor. The FM architecture is using the d...

Polyphase filter outputs

Hi, I am almost a complete newbie when it comes to DSP. I've been studying various internet articles a lot over the last week but I still have some questions that I don't understand. What I'm trying to accomplish is to resample an audio signal to change it's pitch. I don't care if the length c...

Polyphase decimation errors

Folks, I understand that, based on the Nobel Identities, the output of a polyphase decimator should be identical to the output of a basic FIR decimator. This is due to the fact that even though we decimate in the full input bandwidth all the undersampled aliases will exactly cancel in the fina...

Intel's polyphase resampling function

Hi, All. I'm trying to use Intel's IPP polyphase resampling functions. They are part of the signal processing set and found in the manual under Speech Recognition Functions. I've found the manual's usage description somewhat lacking. I don't understand it well enough to implement. Can an...

uniform filter bank implementation.

I have a question with regards to going from a polyphase decimation routine and adapting it to an actual filter bank to separate a large bandwidth into smaller subbands. I understand how polyphase filters works, that no problem, I am just stuck on seeing how you make the transistion to a MxL (...

Regarding Acoustic Echo Cancellation with subbanding

Dear Sir, I am working on Acoustic Echo Cancellation. I have implemented both AEC without subbanding and AEC with subbanding in C+ +. For subbanding of AEC I used Polyphase IIR filter(with 70dB attenuation). AEC without subbanding is working fine. But in the outputs ...

Re: Farrow interpolation in QPSK synchro

Let me try to summarize Farrow's idea in three bullet points: The numbers are from the reference. * I can use a FIR filter to interpolate one particular point between samples, for example at an offset of 1/32 sample time * I keep 32 different banks of FIR coefficients at hand, so that I can c...

Polyphase decimating filter - not working - why?

Hello...I created a polyphase decimating filter based on F.Harris's book shared register design. This is a Decimation by 2, 100 tap, Fs =100MHz, Low pass 20MHz - stop band 24MHz filter. Each MAC is 28-bit length, 14-bit ADC input, and the filter output is truncated. The filter looks good a...