How to select peak data and min data from noise in spectrum?

Hello Guys,

I want to take upside and downside noise signal from my spectrum (the dashed line) just like on this figure. Here, I attach the figure and the excel data. Please can anyone help me with this?.

Thank you, I waiting for your humbly answers

Answer 1

[Emmanuel J Rodriguez]

Hello!

This should do it:

%% Import data
x = xlsread('Spectrum.xlsx','Sheet1','A1:A2503');
y = xlsread('Spectrum.xlsx','Sheet1','B1:B2503');

%% Plot data
plot(x,y)
hold on;
%% Find peaks and dips in the signal
% Peaks
[pks, pks_locs] = findpeaks(y,x); % Finds peaks and their locations
plot(pks_locs, pks, '--k') % Plots a black dashed-line connecting peaks
% Dips
[dip, dip_locs] = findpeaks(-y, x); % Find dips and their locations
plot(dip_locs, -dip, '--k') % Plots a black dashed-line connecting dips
hold off;

Cheers,

Manny

[Sabella Huang]

Ok, It's work. Thanks for your help