Best FIR Coefficients for multirate app

Started by Robin Siegemund in comp.dsp17 years ago 3 replies

Hello for this newbie question! I'm on developing a simple audio-sequencer application. So, if I want to play a 44100Hz samplesound with a...

Hello for this newbie question! I'm on developing a simple audio-sequencer application. So, if I want to play a 44100Hz samplesound with a default note at D4 like a drum at lower notes like C4,F3,E3,etc., I have to decimate to the according sampling-rate. But of course, to prevent aliasing, there must be a lowpass filter before decimation. The best way to to this very efficient is an FIR-...


Anti-Doppler

Started by Max in comp.dsp6 years ago 9 replies

The 'Doppler' thread got me wondering: How would you undo doppler effects to a signal without generating too many inaccuracies. The pitch shift...

The 'Doppler' thread got me wondering: How would you undo doppler effects to a signal without generating too many inaccuracies. The pitch shift is gradual, so there's no way to simply precompute some multirate formula. I'm sure this kind of thing must be common in some sectors. Any ideas on how it's normally implemented?


[Q] How can the chirp-z transform be used in resampling?

Started by One Usenet Poster in comp.dsp14 years ago 6 replies

DSP Gurus: I'm familiar with the classic interpolate-filter-decimate approach to multirate DSP. I've heard that the chirp-z transform can be...

DSP Gurus: I'm familiar with the classic interpolate-filter-decimate approach to multirate DSP. I've heard that the chirp-z transform can be used to resample a signal also. Can anyone provide additional information or references (other than Google search results)? Thanks, OUP


Resampling for multirate system help

Started by billysdomain in comp.dsp14 years ago 6 replies

Hi I need to resample a 32Khz signal into a 8Khz signal, and then back again to 32Khz after it has been processed and am looking for some...

Hi I need to resample a 32Khz signal into a 8Khz signal, and then back again to 32Khz after it has been processed and am looking for some guidance. I am using a dsPIC and have the following two library functions available to me, FIRDecimate and FIRInterpolate, I am also using the dsPICfd software to create my filters. After reading many tutorials on doing this, I am still a bit disorienta...


harris errata?

Started by yahugh in comp.dsp13 years ago 1 reply

I'm working my way through fred harris's Multirate Signal Processing text and have found at least one error. Does anyone know of a site where...

I'm working my way through fred harris's Multirate Signal Processing text and have found at least one error. Does anyone know of a site where errata have been published for this book? Maybe it's time to start an unofficial site. I'll make the first contribution! Hugh


Polyphase Filters

Started by commsignal in comp.dsp9 years ago 4 replies

Hello all, Can someone explain to me the following in Fred Harris' book Multirate Signal Processing for Communication Systems? 1. Chapter 6...

Hello all, Can someone explain to me the following in Fred Harris' book Multirate Signal Processing for Communication Systems? 1. Chapter 6 (page 143 - Separating the Aliases): The inputs to the M-path filter are not narrowband, and phase shift alone is insufficient to effect the destructive cancellation over the full bandwidth of the undesired special contributions (and the next sentence re...


Sampling rate conversion

Started by cpshah99 in comp.dsp12 years ago 9 replies

Hi All I have a carrier modulated signal which is sampled at 48KHz and 12 samples/symbol. Now, I want to resample this signal, so that the...

Hi All I have a carrier modulated signal which is sampled at 48KHz and 12 samples/symbol. Now, I want to resample this signal, so that the new signal has sampling rate of 47968 Hz. Is there any possible way of doing it.? I totally new to this multirate dsp topic. Your opinion matters a lot. Thanks. Chintan


up conversion using multirate technique from DC

Started by samberhanu in comp.dsp4 years ago 4 replies

This is something I thought I would be able to do, but seems that I am runn= ing through issues. I have a CPM spectrum signal that I want to...

This is something I thought I would be able to do, but seems that I am runn= ing through issues. I have a CPM spectrum signal that I want to convert to an IF of 600MHz. The source is an IQ pair converted at a DAC rate of 400 MHz. (2nd DAC Zone) I thought why not=20 a ) put the complex signal pair at Fs/4 sampled at 100MHz b) get the bandpass signal (Re{. } =3D> I - Q) c) downsample


summer school/course

Started by Mike in comp.dsp14 years ago

Hi guys, I am looking for some summer school/courses in Euro or USA 2007 regarding: multirate, subband signal processing OR beamforming,...

Hi guys, I am looking for some summer school/courses in Euro or USA 2007 regarding: multirate, subband signal processing OR beamforming, microphone array But it is really hard to find those summer school/courses. Does anybody have any clue? Your help is really appreciated! Best regards


Blind System Identification

Started by Greg Berchin in comp.dsp13 years ago 6 replies

Okay, so I'm trying to work my way through "Blind System Identification and Channel Equalization of IIR Systems without...

Okay, so I'm trying to work my way through "Blind System Identification and Channel Equalization of IIR Systems without Statistical Information", by Bai and Fu; specifically "Algorithm 4.1". Though the nomenclature seems to be standard for multirate systems, it is cumbersome. But I think I've got a good handle on the technique, up to the point just beyond equation (4.6), where it says: ....


multirate papers

Started by tureface in comp.dsp12 years ago 1 reply

Hello , I`m doing a research for multi-rate technique and i need this 2 very important basic paper that i did not find in web : 1) Croisier,...

Hello , I`m doing a research for multi-rate technique and i need this 2 very important basic paper that i did not find in web : 1) Croisier, A. ,Esteban , D., and Galand "Perfect channel splitting by use of interpolation/decimation/tree decomposition techniques" Int.Symp.on Info.,Circuit and Systems, Patras,Greece, 1976 2)Ramstad,T.A. "analysis/synthesis filter banks with critical samp...


Cascaded Integrator Comb and aliasing experts please help!

Started by David Joseph Bonnici in comp.dsp16 years ago 3 replies

Please refer to www.intersil.com/data/fn/fn3651.pdf page 10 top and page 9 bottom. Please correct me if I assume something wrong. On...

Please refer to www.intersil.com/data/fn/fn3651.pdf page 10 top and page 9 bottom. Please correct me if I assume something wrong. On figure 12 (pg 10) you see the aliasing profile of the CIC and how it does it translate to baseband. The filters performance can therefore be estimated. Quite understandable and easily programmable. (and it does apply to all multirate filters) Now the q...


Multirate filters

Started by maverick.gvs in comp.dsp12 years ago 1 reply

hi all, I am working on polyphase filter bank design. I want some pointers on (i)how to avoid aliasing from other bands? (ii)what are the...

hi all, I am working on polyphase filter bank design. I want some pointers on (i)how to avoid aliasing from other bands? (ii)what are the important steps while considering the design of prototype filter? (iii)How to avoid the amplitude distortion? (iv)How to design filter banks with different passband widths? thanks in advance vanamali


Do multirate filters break I/Q mod/demod?

Started by sal p in comp.dsp13 years ago 5 replies

I have a question regarding I/Q modulation occuring in a multi-rate system. Here's the background: fs = 20e6; fc = 20e6; (my carrier...

I have a question regarding I/Q modulation occuring in a multi-rate system. Here's the background: fs = 20e6; fc = 20e6; (my carrier freq) I = cos( 5mhz ) Q = 0; I first upconvert both I and Q to fs = 120e6 in two stages, interp by 4, and interp by 3/2. Then I form the passband signal: passband = I*cos( fc ) - Q*sin( fc ). Now I retrieve the I and Q components by I_rcv = passband...


Cascaded Integrator Comb and aliasing experts please help!

Started by David Joseph Bonnici in comp.dsp16 years ago 5 replies

Thanks for not losing your patience. I am going to make a resume of what my intentions are and list my two questions in order of priority. I...

Thanks for not losing your patience. I am going to make a resume of what my intentions are and list my two questions in order of priority. I receive your postings with a latency of 5 hours so if someone has already made postings giving me solutions please discard these message. Question 1: I need to compute the aggregate frequency response of three cascaded multirate filters. I was tryi...


mixing pcm

Started by Willy in comp.dsp15 years ago 3 replies

hello, be aware, I'm new to DSP algorithms :) I have more pcm streams. first I have to change the sample rates of some pcm streams and than...

hello, be aware, I'm new to DSP algorithms :) I have more pcm streams. first I have to change the sample rates of some pcm streams and than I have to "add" all streams in a (new) pcm stream (with a given sample rate). How can I do this? As I read on the dspguru.com, changing the sample rate might be done with using multirate algorithm. But how can I do the "sampling" of the streams?...


Comparing input and output of multirate system

Started by pompano in comp.dsp13 years ago 4 replies

I have designed a front end to a com system (in Matlab) that takes an input IF, does Fs/4 down conversion, and then then down-samples by a...

I have designed a front end to a com system (in Matlab) that takes an input IF, does Fs/4 down conversion, and then then down-samples by a variable amount through a series of halfbands. A sharp FIR filter is then applied to get the desired signal. I've been asked to show a nice plot with the original and the output spectrums overlayed, but I'm having a little trouble with this. I take approp...


Design of multirate filters

Started by Anonymous in comp.dsp12 years ago 20 replies

Hi i am simulating a baseband OFDM system Digital down converter. I have a problem regarding decimation and interpolation. In the last stage of...

Hi i am simulating a baseband OFDM system Digital down converter. I have a problem regarding decimation and interpolation. In the last stage of the DDC, i am doing low pass filtering of the data. My problem is when i make a sharp transition filter i.e. ( Fpass = 250e3; % Passband Frequency Fstop = 300e3; % Stopband Frequency the OFDM constellation is scattered. But...


FIR Interpolation question

Started by Roger Waters in comp.dsp17 years ago 36 replies

This question relates to the Multirate FAQ at the dspGuru site: http://dspguru.com/info/faqs/multrate/interp.htm I have a 256 element array...

This question relates to the Multirate FAQ at the dspGuru site: http://dspguru.com/info/faqs/multrate/interp.htm I have a 256 element array that I want to interpolate at a variable density, between 4 and 10. Let's take the first case, i.e. the interpolation factor or density, L = 4. Thus, I need a 256 * 4 = 1024 tap filter. My question is this: How do I obtain the coefficients of th...


Multirate filter

Started by alexgaas in comp.dsp11 years ago 7 replies

Hi everybody! I'm working on a UWB radar and i have an analog front end that samples the input signal in a nonuniform way. For the...

Hi everybody! I'm working on a UWB radar and i have an analog front end that samples the input signal in a nonuniform way. For the reconstruction filter i would use a nonuniform reconstruction algorithm from IEEE transaction on signal processing.These are links : http://www.rle.mit.edu/dspg/documents/00Eldar.pdf webee.technion.ac.il/Sites/People/YoninaEldar/Info/70.pdf The second link ...