Hi,
To remove high frequency noise, pass the signal through low pass filter.
Low pass filter can be of averaging filter, butterworth filter, Chebyshev filter etc..
Please refer the below example code for low pass filter with butterworth and averaging filter (averaging FIR filter)
load('data_f.mat');
plot(flow_S);
%% butterworth filter low pass filtering
%[b,a] = butter(3,0.1,"low");
%% normal average filter in place of butterworth filter
b = (1/20)*ones(1,20);
a = 1;
%% filtering
out = filter(b,a,flow_S);
hold on
plot(out);
