Dear klystron,
Thank you very much for your suggestion.
Actually I have tried moving average, after that a similar signal pattern is generated. however, with unknown threshold, I still cannot identify the 'spike' or 'peak'. please see attachment. in the figure, blue curve is original signal, red curve is the one after moving average.
Would you please elaborate more about the 'peak detector', assuming that we know nothing about the threshold? thanks a lot.
best regards,
tenderne