lms notch adaptive filter

Started by el01...@mail.ntua.gr in Matlab DSP14 years ago

hello, > > im new to the topic of adaptive filters and its implementation in matlab. im doing a project on 'filtering an ECG foetus'. we...

hello, > > im new to the topic of adaptive filters and its implementation in matlab. im doing a project on 'filtering an ECG foetus'. we are carrying out all our analysis on an ECG wave with only a powerline interference (60hz). > > the signal available to us is an ECG wave with a noise component of 60hz, sampled at 360hz.. > can you help me implement an adaptive filter using LMS algorithm f


comb filter of time domain average(or time synchrounous average) matlab code

Started by winstonliu1975 in Matlab DSP18 years ago

I would like to ask the people who have experiences in fault diagnosis of rotationary machinery. The existing comb filter model...

I would like to ask the people who have experiences in fault diagnosis of rotationary machinery. The existing comb filter model of time domain averaging is a signal processing technique which may be used to extract repitive signals from additive noise. And this algorithm for p


Noise Cancellation using MATLAB

Started by nata...@hotmail.com in Matlab DSP12 years ago 1 reply

Hello, I'm Natasha and I'm doing my project on ' active noise cancellation in headsets'. I am new to MATLAB and have written a code for noise...

Hello, I'm Natasha and I'm doing my project on ' active noise cancellation in headsets'. I am new to MATLAB and have written a code for noise cancellation of an audio signal using a simple lms filter. However, the program shows errors,particularly in the lms filter designing area; [d,r] = wavread('df3_n0H.wav.wav'); r =8500 size(d) ans =42500 M = 32; mu=0.004;...


Changing sampling frequency

Started by israel Greiss in Matlab DSP12 years ago

A filter designed at 1kHz sampling rate, when used at 4kHz sampling rate, its frequency response will be stratched 4 times. For example the...

A filter designed at 1kHz sampling rate, when used at 4kHz sampling rate, its frequency response will be stratched 4 times. For example the new cut-off frequency will be 4 times the original. If you want to keep similar frequency responce as the original, you need to redesign the filter. Normally you have to use more cofficients in the new design in order to keep the same shape. Use the filt...


IIR filter design code

Started by Nalin K Pithwa in Matlab DSP17 years ago

Hi, I have tried to implement MATLAB codes for IIR Filter design with bilinear transformation. However, I do not get the correct mag...

Hi, I have tried to implement MATLAB codes for IIR Filter design with bilinear transformation. However, I do not get the correct mag & phase plots for Chebyshev Type II. In the case of Elliptic, I do not even get the correct order by using "ellipord". I am attaching the design specs and MATLAB codes. Please throw some


Re: problems implementing 8th order bessel-filter

Started by in Matlab DSP14 years ago

Dear Dwisuu, I think I know what's is going wrong. You are using the coefficients in the s-domain in a command that you should feed with...

Dear Dwisuu, I think I know what's is going wrong. You are using the coefficients in the s-domain in a command that you should feed with coefficients in the z-domain. You are trying to make an analog filter using the command "besself" and matlab is returning coefficients in the s-domain, when you use the matlab command "filtfilt" matlab thinks that you are entering with z-coefficients. All...


decimation filter for high order decimation rate

Started by itamare1982 in Matlab DSP10 years ago

Hi ALL I working on application that i need to sample 1.9Khz signal by 1Mhz , its mean 512 OSR - AFTER SIGMA DELTA MODULATION ( FOR SEPARATE...

Hi ALL I working on application that i need to sample 1.9Khz signal by 1Mhz , its mean 512 OSR - AFTER SIGMA DELTA MODULATION ( FOR SEPARATE the quantization noise from the signal) i need to decimate the signal by decimation rate of 512. i decided to use CIC filter to decimate by 128 and then cascade more 2 FIR - one as compensator and the other for the phase linearization. the DC gain in t...


raised cosine filter help

Started by asim...@yahoo.com in Matlab DSP16 years ago

i want to design a raised cosine filter in passband..i-e after modulation with the carrier of 10 MHz sin wave...here is my code .......... f_c...

i want to design a raised cosine filter in passband..i-e after modulation with the carrier of 10 MHz sin wave...here is my code .......... f_c = 4; % Carrier frequency j=1 for k=1:600 %length(sig), for t=0:1/(20*f_c):1, r(j)=spdata(k)*cos(2*pi*f_c*t); % BPSK (spdata is +1 or -1) j=j+1; end end over = 160; % oversampling factor pulse = rcosine(80,over,'normal'


design filter from freq. response

Started by suni...@qualcorelogic.com in Matlab DSP16 years ago 2 replies

hi everybody, I don't know much about Matlab. I have just started working on matlab. Now I want to design a filter using remez algorithm. I have...

hi everybody, I don't know much about Matlab. I have just started working on matlab. Now I want to design a filter using remez algorithm. I have my own freq. response; specified freq. response is not standard lowpass, highpass, bandpass or bandstop. Basically it is lowpass but its band pass region is a parabolic curve. So I was taking inverse fft of the freq spectre and then I was applying windo...


Frequency response to Impulse response conversion

Started by sudheer nair in Matlab DSP20 years ago 1 reply

Hi All, I want the impulse response of a filter from its frequency response. I have the required frequency response of my ...

Hi All, I want the impulse response of a filter from its frequency response. I have the required frequency response of my filter--but the frequency response is specified for some frequencies only. For example: Let F be the list of frequencies at for which I h


Kalman Filter for Clock Phase Drift

Started by albr...@gmx.de in Matlab DSP12 years ago

I am looking for Matlab code for a Kalman filter for oscillator clock phase drift estimation. In particular, tracking long-term phase drift (not...

I am looking for Matlab code for a Kalman filter for oscillator clock phase drift estimation. In particular, tracking long-term phase drift (not short-term jitter). Any ideas how to use the KALMAN function for this purpose?


Nonlinear fir filter design

Started by Appalayagari Sreedhar in Matlab DSP20 years ago 1 reply

Hi I want to know clearly, what exactly the non linear phase fir filters. is the minimum phase fir filters are the nonlinear...

Hi I want to know clearly, what exactly the non linear phase fir filters. is the minimum phase fir filters are the nonlinear filters. i need to design a non linear filter,please shed some light on this area. thank u all, and also does the anti


how to chnage a bandpass filter to a low pass filter

Started by taisa ahmad in Matlab DSP16 years ago

hello and good day ! A pass band receiver system will process modulated signal , i.e. there iz RF stage , then IF stage and Baseband...

hello and good day ! A pass band receiver system will process modulated signal , i.e. there iz RF stage , then IF stage and Baseband (BB) stage. I want to model LPF instead of BPF in RF and IF stage i.e. model a LPF from a BPF, which gives the same output as passband system gives. I tackle this problem that i take hilbert transform to retain only positive frequencies and...


Nyquist fir filter design for pulse shaping

Started by msrvasug in Matlab DSP14 years ago

Hi, I have to design a nyquist interpolation filter which should satisfy all the properties of pulse shaping i.e zero ISI and nonnegative...

Hi, I have to design a nyquist interpolation filter which should satisfy all the properties of pulse shaping i.e zero ISI and nonnegative magnitude response etc.First I thought using remez algorithm 'firgr' function but it doesn't optimize time domain response.So now I have seen 'firnyquist' function in the matlab for my design. But it is only taking order,rolloff factor,inetpolation fact...


Ridge frequncy estimation of fingerprint image for Gabor filter

Started by paria rahmani in Matlab DSP16 years ago

Hi.I'm working on fingerprint image enhancement & minutiae extraction,i don't know how to estimate ridge frequency of fingerprint image to...

Hi.I'm working on fingerprint image enhancement & minutiae extraction,i don't know how to estimate ridge frequency of fingerprint image to filtering by Gabor filter(in time domain not in frequency domain).if anyone can help me,please contact me. Thanks a lot.


MATLAB Impulse response of a Comb filter

Started by "hyp...@yahoo.com [matlab]" in Matlab DSP8 years ago

Hi, I am an FPGA engineer , new to MATLAb and DSP , and immersed in DSP study. Today's exercise is plotting the unit impulse response for a Comb...

Hi, I am an FPGA engineer , new to MATLAb and DSP , and immersed in DSP study. Today's exercise is plotting the unit impulse response for a Comb filter of the form: yc(n) = x(n) - x(n-4) I wrote the following code: n1 = 0; n0 = 10; % t = 0 n2 = 100; % n2 - n1 = Length of impulse response in vector [x,n] = impseq(n0,n1,n2); % Generates unit impulse sequences, x(n0) = 1, others 0 % Dif...


need help to design a 2nd order digital low pass filter

Started by roksy smith in Matlab DSP17 years ago 1 reply

hey guys ... please anyone help me to design a 2nd order digital low pass filter. Its specifications are as below: passband: fpass<= 1.5khz ...

hey guys ... please anyone help me to design a 2nd order digital low pass filter. Its specifications are as below: passband: fpass<= 1.5khz stopabnd: fstop >= 3khz sampling frequency: fs = 10 khz from this i have to find pole-zero diaram ,sample response h(k),a block diagram implemation and freqency response... thanking you.. roksy


Modeling a Rician channel

Started by Morris Vian in Matlab DSP12 years ago

Hi, I am using the "ricianchan" command to create my fading channel and then use the "filter" command to filter a baseband signal. However, I...

Hi, I am using the "ricianchan" command to create my fading channel and then use the "filter" command to filter a baseband signal. However, I am left wondering if this setup will accurately model the Doppler frequency spread. Since the Doppler frequency spread is function of the carrier?s center frequency, would I need to first modulate my baseband signal to RF frequencies, pass it throu


Filter question

Started by narokel in Matlab DSP19 years ago 2 replies

Hello, I have a question about filters. From my understanding, a filter takes in an input signal and produces a resulting...

Hello, I have a question about filters. From my understanding, a filter takes in an input signal and produces a resulting output signal. Are there filters that take in more than one input signal, and produce the resulting output signal. If there are such multi-input


Bandpass filter 2dFFT

Started by Ibrahim muhammed in Matlab DSP13 years ago

Hi there, I have a 2d data, with space x time (longitude and time). I need to do a bandpass filter while taking windows on both dimensions....

Hi there, I have a 2d data, with space x time (longitude and time). I need to do a bandpass filter while taking windows on both dimensions. Dimension 1 is space and dimension 2 is time. For space, my window should be between 5.4 to 7, and for time is 1.5 to 4. I started as: data=data(:,:); %1:180 x 1:225 [Ns,Nt]=size(data); Ts=1/4; % each unit of space is 0.25 of a degree Tt=10/...