Find turning point of noisy signal

Hello all

I would like calculate transport delay time between desired and measured signal. I tried many methods like diff or two times diff or ischange or etc. However, I could find any robust solution to catch the red point (the point where the signal starts to rise).

Could you please give me idea how can I can detect this point without using Signal Processing Tool box? Thanks in advance

Answer 1

[Image Analyst]

Try findchangepts. If it doesn't work well then first try to denoise your signal by running it through movmedian.

Another option is to just set a threshold where if the signal exceeds it, it's begun to rise.

threshold = 5; % Whatever it might be.
index = find(y > threshold, 1, 'first')
tStart = t(index)
yStart = y(index)