# how to use the hanning window to smooth the photon signal

28 views (last 30 days)

Show older comments

windowLength = 91;

hannWindow = hann(windowLength);

smooth_data = conv2(data, hannWindow, 'same');

is the code correct? Because when i increase the windowlength, the smooth_data will increase as well

##### 0 Comments

### Answers (2)

Alexander
on 19 Feb 2024

I can't see this effect you mentioned. smooth_data remains the same size as data (I assume data = Photoncounts1). What do you expect? I never used windowing in the manner you have done it in the code above. Usually I multiplied the data with the window (or parts of the window) in the time domain to get rid of the step function and having a clear transient effect before a fft. Just an example:

clear;

N = 1024;

x = 0:N-1;

Whann = hann(N)';

y = rand(1,N); % Create some data

subplot(211);

plot(x,y);title('Original');grid minor;

subplot(212);

plot(x,y.*Whann);title('Windowed');grid minor;

##### 3 Comments

Alexander
on 20 Feb 2024

Star Strider
on 19 Feb 2024

That appears to be some sort of spectrum. I am not certain what you want to do with it, however windowing it is not likely to produce any benefit at this point.

load('photon.mat')

% whos

figure

stairs(Photoncounts1)

grid

xlabel('Bin (?) Frequency (?)')

ylabel('Counts')

title('Photons')

xlim([0 600])

If this is a Fourier transform, the time to window the data was before calculating the transform.

.

##### 6 Comments

### See Also

### Categories

### Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!