- 9th April 2007, 06:19 #1

- Join Date
- Jan 2007
- Posts
- 32
- Helped
- 5 / 5
- Points
- 1,261
- Level
- 8

## fir filter matlab

Can anybody help to find our FIR filter design for random noise removal.

- 9th April 2007, 10:26 #2

- Join Date
- Dec 2006
- Posts
- 165
- Helped
- 16 / 16
- Points
- 2,199
- Level
- 10

## matlab noise filter

What is the type of filter you want? You can use the filter design tool box that comes with matlab (check matlab help).. A simple cammand fir will design the filter for you..

1 members found this post helpful.

- 13th April 2007, 09:48 #3
## fir matlab

What kind of signal do you use? Filter must be matched to your signal.

1 members found this post helpful.

- 13th April 2007, 09:55 #4

- Join Date
- Apr 2007
- Posts
- 134
- Helped
- 8 / 8
- Points
- 1,500
- Level
- 8

## fir filter matlab code

Your FIR should be a low pass in nature, but the specification has to be extracted from noise spec.

- 13th April 2007, 11:48 #5
## matlab fir

in general cases

Find the noise variance or estimate it

use the "fspecial" to design u r quick gaussian filter

might work easily ..but it depends of the noise distribution...

If u want a real good answer....u r questions must be very specific

- 13th April 2007, 11:48

- 17th April 2007, 06:50 #6

- Join Date
- Jan 2007
- Posts
- 107
- Helped
- 1 / 1
- Points
- 1,550
- Level
- 8

## noise filter matlab

Originally Posted by**ztanish**

- 17th April 2007, 06:50

- 17th April 2007, 12:43 #7

- Join Date
- Mar 2007
- Posts
- 4
- Helped
- 0 / 0
- Points
- 1,041
- Level
- 7

## matlab filter noise

use fdatool in Matlab

>> fdatool

br

- 17th April 2007, 16:02 #8

- Join Date
- Apr 2007
- Posts
- 7
- Helped
- 0 / 0
- Points
- 1,053
- Level
- 7

## matlab code for fir filter

Filtering noise through a simple Low Pass filter will be a naive method but its a good step if its your first try.

As a first step check out "fir1" in matlab.

bye.

- 17th April 2007, 16:02

- 18th April 2007, 17:18 #9

- Join Date
- Dec 2006
- Posts
- 32
- Helped
- 6 / 6
- Points
- 1,653
- Level
- 9

## filter noise matlab

Use FDATOOL in matlab. If you type

>> fdatool

in command window, Fda tool will be opened. There you can select FIR or IIR filter, order of filter and cutoff freq. of filter (either HPF, LPF or BPF). That code will automatically generate .m file for you.

1 members found this post helpful.

- 18th April 2007, 17:47 #10

- Join Date
- Jan 2007
- Posts
- 25
- Helped
- 10 / 10
- Points
- 1,490
- Level
- 8

## matlab fir filter

Hi,

Try this " help firwiener " and read how to use. This is easy step to filtering noise and no need to design in "fir" function learn it as benchmark, then u should design parameter of "fir1" for filtering by yourself.

- 20th April 2007, 18:36 #11

- Join Date
- Apr 2007
- Posts
- 14
- Helped
- 2 / 2
- Points
- 1,321
- Level
- 8

## matlab fir filter design

Originally Posted by**maomun**

tanks for help

- 20th April 2007, 19:24 #12
## fir filter in matlab

try using matlab for moving avg filters

2 members found this post helpful.

- 23rd April 2007, 09:39 #13
## matlab program for fir filter

give ur email id i 'll send the code to u as a .m file.

2 members found this post helpful.

- 24th April 2007, 06:54 #14

- Join Date
- Jun 2005
- Posts
- 186
- Helped
- 7 / 7
- Points
- 2,123
- Level
- 10

## matlab fdatool

you should know what type filter matched to your apllications, LPF,BPF,or HPF, then you should know what charateristic the filter have , such as cut off frequency , ripple wave in passband and attenuation! wish it helps !

- 30th September 2007, 08:00 #15

- Join Date
- Sep 2007
- Posts
- 2
- Helped
- 0 / 0
- Points
- 935
- Level
- 6

## fdatool matlab

Originally Posted by**ztanish**

send tat to my mail id tejaswi.subash@gmail.com

Added after 5 minutes:

Originally Posted by**cydi**

my email id is tejaswi.subash@gmail.com

Added after 29 seconds:

Originally Posted by**Unomano**

my email id is tejaswi.subash@gmail.com

thank you

Added after 10 seconds:

Originally Posted by**Unomano**

my email id is tejaswi.subash@gmail.com

thank you

Added after 1 minutes:

Originally Posted by**helios**

my email id is tejaswi.subash@gmail.com

Added after 49 seconds:

Originally Posted by**armess**

Originally Posted by**sprao**

- 9th August 2009, 12:57 #16

- Join Date
- Aug 2009
- Location
- chennai
- Posts
- 1
- Helped
- 0 / 0
- Points
- 596
- Level
- 5

## noise filtering matlab

clear all;

close all;

rp=input('enter the pass band ripple');

rs=input('enter the stop band ripple');

fp=input('enter the pass band ferquency');

fs=input('enter the stop band frequency');

f=input('enter the sampling frequency');

wp=2*fp/f;

ws=2*fs/f;

num=-20*log10(sqrt(rp*rs))-13;

dem=14.6*(fs-fp)/f;

n=ceil(num/dem);

n1=n+1;

if (rem(n,2)~=0);

n1=n;

n=n-1;

end

y=boxcar(n1);

b=fir1(n,wp,y);

[h,o]=freqz(b,1,256);

m=20*log10(abs(h));

subplot(2,2,1);

plot(o/pi,m);

- 9th August 2009, 14:03 #17

- Join Date
- Dec 2006
- Location
- Malaysia
- Posts
- 1,142
- Helped
- 395 / 395
- Points
- 19,911
- Level
- 34

## fir filter design matlab

Originally Posted by**pranchith**

thanks

- 9th August 2009, 17:16 #18

- Join Date
- Oct 2008
- Location
- Sindh, Pakistan
- Posts
- 896
- Helped
- 178 / 178
- Points
- 9,408
- Level
- 23

## fir in matlab

for good results you may want to use either Kaiser's or Blackman's window. The rectangular window wold not give good attenuation in the stop band

1 members found this post helpful.

- 24th November 2009, 07:41 #19

- Join Date
- Nov 2009
- Location
- N.I.T.,kurukhetra
- Posts
- 2
- Helped
- 0 / 0
- Points
- 548
- Level
- 4

## Re: Matlab code for FIR filter design

i want a matlab code for filter design using kaiser window

- 19th March 2010, 07:51 #20

- Join Date
- Jun 2009
- Location
- bangalore
- Posts
- 4
- Helped
- 0 / 0
- Points
- 649
- Level
- 5

## Re: Matlab code for AWGN filter

Hi all.

i have added AWGN to my speech signal, how to filter it out,?

how to know the frequency of the gaussian noise that i have added, plz do reply