DSPRelated.com

using IIR filter library for C2000 DSP

Started by Simon in comp.dsp18 years ago 1 reply

Hi, I wanna implement a low pass IIR filter in C2407 using the 24x Filter library. I am a new comer to this kind of implementation. ...

Hi, I wanna implement a low pass IIR filter in C2407 using the 24x Filter library. I am a new comer to this kind of implementation. /*After the initation:*/ { iir.dbuffer_ptr=dbuffer; iir.coeff_ptr=coeff; iir.qfmat=IIR_LPF_QFMAT; iir.nbiq=IIR_LPF_NBIQ; iir.isf=IIR_LPF_ISF; iir.init(&iir); } while(ADUPDATE) /*new adc coming*/ { ...


IIR on TI 55xx

Started by AntonZ in comp.dsp14 years ago 3 replies

I try to implement an IIR on a 16-bit fixed-point 5510 DSP. After calculating the filter in Matlab, I got the following coefficients: > > ...

I try to implement an IIR on a 16-bit fixed-point 5510 DSP. After calculating the filter in Matlab, I got the following coefficients: > > iir.tf.num ans = 1.0e-005 * 0.0868 0.3470 0.5205 0.3470 0.0868 > > iir.tf.den ans = 1.0000 -3.8373 5.5250 -3.5375 0.8498 Now I decompose the filter into two biqads: > > tf2sos(iir.tf.num,iir.tf.den) ans


Implementing IIR on Xilinx?

Started by androm in comp.dsp19 years ago 1 reply

Hi, I am trying to implement a filterbank with IIR on Xilinx FPGA. Does anyone have experience on similar project? Right now, I am using...

Hi, I am trying to implement a filterbank with IIR on Xilinx FPGA. Does anyone have experience on similar project? Right now, I am using direct form I second-order-series for the IIR. However, when I tried to generate the vhdl code in simulink, I was informed that the timing constraints could not be met. I think the problem might comes from the feedback loop in the IIR. Anyone could help? ...


IIR approximation with FIR

Started by OutputLogic in comp.dsp13 years ago 29 replies

I need to implement a certain IIR filter in FPGA. The circuit has to process several samples in one clock, which requires to unfold the...

I need to implement a certain IIR filter in FPGA. The circuit has to process several samples in one clock, which requires to unfold the IIR feedback loop. If I do that, the circuit area and critical path become too large. My question is if there is a reasonably simple algorithm to approximate IIR with FIR. I've seen lengthy and impractical academic papers on how to do it. At this point I'...


First order IIR filter

Started by Rohit in comp.dsp15 years ago 13 replies

Dear All, I do not have any background in DSP, so please excuse if this question seems silly. I am working on a bugfix for an IIR filter...

Dear All, I do not have any background in DSP, so please excuse if this question seems silly. I am working on a bugfix for an IIR filter implementation in C. It takes samples from ADC and filters them. Filtering is done by an First order IIR filter. The transfer function is as follows: /* First order IIR filter z-transform(formula): [ 2^-n/(1-(2^-n)) ] ...


IIR for image processing in Matlab. How???? (Plz help)

Started by Anonymous in comp.dsp19 years ago 2 replies

Hello, would any one out there can help me how to appy IIR to filter an 256x256 image using IIR in Matlab? is there any function for it (I...

Hello, would any one out there can help me how to appy IIR to filter an 256x256 image using IIR in Matlab? is there any function for it (I mean 2 D IIR filter). I have to use a IIR filter to filter a image and it is required that I do it in Matlab. I have done it in C and using difference equation: y(m,n)=a1*x(m,n)+a2*y(m-1,n)+..... and everything is fine. Now I have to do it in ...


High sample rate IIR Filters

Started by francis in comp.dsp19 years ago 2 replies

Hi, 3 questions:- 1. I know IIR Filters are used for audio, but are there applications where IIR filters are used in higher sample rates. For...

Hi, 3 questions:- 1. I know IIR Filters are used for audio, but are there applications where IIR filters are used in higher sample rates. For example do IIRs get used in the MHz range. 2. Can I minimise the non-linear phase characteristics of the IIR? 3. Is there a good book that delas with digital filter architectures? Mike This message was sent using the Comp.DSP web inter...


What am I missing about IIR Filter Design?

Started by FilterDan in comp.dsp10 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...


LPC experiment

Started by Mauritz Jameson in comp.dsp12 years ago

I created a MATLAB script which runs through 10000 tests. In each test a random signal is created and IIR filtered. The IIR numerator is 1 and...

I created a MATLAB script which runs through 10000 tests. In each test a random signal is created and IIR filtered. The IIR numerator is 1 and the IIR denominator is: 1 -1.99240148160141 3.01948286335539 -2.81852242649452 2.03872063706253 -1.05454462109568 0.414446268750399 -0.115718625236828 ...


IIR filter order

Started by Grant Griffin in comp.dsp14 years ago 7 replies

I'm finally about ready to release an IIR filter design program called - you guessed it - ScopeIIR (TM). It currently supports the basic...

I'm finally about ready to release an IIR filter design program called - you guessed it - ScopeIIR (TM). It currently supports the basic design types of Butterworth, Chebyshev, and Elliptic. I'm trying to finalize the default and maximum IIR filter order that the program will support. To help me do that, please tell me about your experiences with IIR filter order, assuming the above t...


IIR filter question

Started by Rick Lyons in comp.dsp18 years ago 37 replies

Hi Guys, I was asked to review a potential article for the IEEE Sig. Proc. magazine. In that article the author implies that IIR...

Hi Guys, I was asked to review a potential article for the IEEE Sig. Proc. magazine. In that article the author implies that IIR (recursive) filters aren't as popular nowadays as they were in the past (say 10-20 years ago). Now I'm no IIR filter designer, so I need your opinions. Aren't IIR filters still as popular now for audio signal processing as they were 10 years ag...


PI implementation using IIR

Started by maanas in comp.dsp15 years ago 3 replies

hello everyone i am new to this DSP world and stuck in a problem. could you please guide me in understanding about PI controller and IIR filter...

hello everyone i am new to this DSP world and stuck in a problem. could you please guide me in understanding about PI controller and IIR filter implementations similarity. i.e whether i can implement IIR for a PI controller. my project : i have to maintain constant current through a load by constantly monitoring it and adjusting the PWM signal to the switch. i was thinking of implementing disc...


about filters

Started by rashmi venugopal in comp.dsp13 years ago 4 replies

is fir filter is benificial or the iir filter for the application to measure the total harmonic distortion in metering equipment. and also...

is fir filter is benificial or the iir filter for the application to measure the total harmonic distortion in metering equipment. and also reasons to select particular filter, fir requires more memory than iir,, but iir is not a linear phase,,


Any shape IIR Filter

Started by sparafucile17 in comp.dsp16 years ago 27 replies

Let's say I have a particular freqeuncy response that I can draw out on paper and I want an IIR filter to do just that. What is the best...

Let's say I have a particular freqeuncy response that I can draw out on paper and I want an IIR filter to do just that. What is the best approach to this problem. I know there are simpler ways to do this using FIR filters but let's say my constraint was to only use the IIR form. For example the frequency shape I need is a smiley face or a parabola. It's not a peak-notch type or a band-reject...


how to get rid of ringing with IIR notch filters?

Started by Anonymous in comp.dsp20 years ago 20 replies

Hello, 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...


ECG Filter IIR vs. FIR

Started by mike2108 in comp.dsp15 years ago 2 replies

I'm just wondering about the reason for choosing an FIR filter over an IIR for ECG signals. If an IIR filter was used for a signal (in this...

I'm just wondering about the reason for choosing an FIR filter over an IIR for ECG signals. If an IIR filter was used for a signal (in this case, an ECG)which contained many signal frequencies of interest, could distortion of the signal be a problem due to the non-linear phase? I only ask because I've seen papers which use IIR filters for ECG noise removal, and I'm wondering if some special ...


IIR FILTER application - A Total Wreck

Started by murali_hd in comp.dsp17 years ago 3 replies

Greetings People, As fate would would have it am working on a project involving IIR filters and am stuck.I would therefore...

Greetings People, As fate would would have it am working on a project involving IIR filters and am stuck.I would therefore request you to give me your opininion on the following issue. The project involves coding in C .Herein the discrete data is read from the sound file(.WAV FORMAT) first and then the formulae for the IIR filter which happens t...


IIR filters design methods?

Started by alixman984 in comp.dsp18 years ago 4 replies

Hello Guys; To be honest, I'm very new to DSP as whole, but because of what i am studying in university i need to know about different IIR...

Hello Guys; To be honest, I'm very new to DSP as whole, but because of what i am studying in university i need to know about different IIR filter design methods. Searched the net and I got next to nothing. I was wondering if anyone here, would mind to share a link or information about IIR design methods. I do appreciate your help. Ali


IIR Coefficient Calculation

Started by ger_lough in comp.dsp10 years ago 29 replies

I am having difficulty finding any info on how to calculate digital IIR filter coefficients. I know this can be done in MATLAB, for example, but...

I am having difficulty finding any info on how to calculate digital IIR filter coefficients. I know this can be done in MATLAB, for example, but I am interested in changing IIR specs on the fly. I have done this before using the formulae provided by Robert Bristow-Johnson on musicdsp.org, but these equations only cover a 2nd order biquad. So, for example, how can I calculate the coefficients for ...


minimum phase IIR : application and design technique?

Started by bharat pathak in comp.dsp13 years ago 7 replies

1. what application area's are min phase IIR's used? 2. what is the design procedure for the same. Recenltly I was going thru the book of...

1. what application area's are min phase IIR's used? 2. what is the design procedure for the same. Recenltly I was going thru the book of proakis and stumbled upon topic on min phase IIR's. so this got me curious to know more. I know min phase FIR's and how to design them but want to know more about min phase IIR's. Regards Bharat