How to Design a Moving average filter?

Hi everyone im kinda new with filter design in Matlab and in need of some help..

So basically i need to reduce the noise in an record and playback system based on DSP TMS320c6713.

Right now im stuck in writing the code for Moving average filter (exponential or simple). so can somebody help me out or give me some examples please.. I've been reading a lot and still dont seem to understand much!! Thanks in advance..

[pankaj jood]

M = movmean(A,k) M = movmean(A,[kb kf]) M = movmean(___,dim) M = movmean(___,nanflag) M = movmean(___,Name,Value)

Answer 1

[Wayne King]

To implement a simple causal moving average filter in MATLAB, use filter()

Ten-point moving average filter

B = 1/10*ones(10,1);
out = filter(B,1,input);

Adjust as needed for a different number of time steps.

[mohsen]

Thank you Wayne.. could u tell me how this works please? i have no idea!!

[Wayne King]

It is mathematically equivalent to

y(n) = 1/N(x(n)+x(n-1)+x(n-2)+....x(n-N))

so for each n, y(n) is the average of the preceding n points.

Obviously at the beginning of the output, y(n), it is an average of fewer points because you don't have N points in the past.

[nani kalyan]

i am having 24000 values, so how can i filter hese all value please will you say me the code to enter in MATLAB SCRIPT.

[Image Analyst]

You can use Wayne's code. I'm going to adapt it slightly to give an odd number for the filter width so there's not a time shift between the output signal and the input signal.

windowWidth = 11; % Whatever you want.
kernel = ones(windowWidth,1) / windowWidth;
out = filter(kernel, 1, yourInputSignal);

[3011]

What code shall I use if I want to develop a simple non-causal moving average filter? what alterations should will there be?

[Christopher Bitikofer]

I think using filtfilt would work... I'm trying to figure something similar out

[Osman Atay Öztürk]

windowWidth = 11; % Whatever you want.

kernel = ones(windowWidth,1) / windowWidth;

out = filter(kernel, 1, yourInputSignal);

How can I know this window width?