You can see a similar shape in the "Highpass" filter curve in the "Filters" chapter. It's more a radish than a bell. Period 1 would probably pass too much noise and make the detection worthless - but you can experiment with different settings and see for yourself. Our systems normally use 20 or 30 for the period.
Would it be ok to use optimize to find the best period or would it cause curve-fitting?
