Filter Analysis and Ripple

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Sam
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Joined: Sat Apr 28, 2018 6:49 pm

Filter Analysis and Ripple

Post by Sam » Tue Mar 15, 2011 4:34 pm

In tweaking my amplifilter, I suddenly got a response that showed 2 dB of ripple in Filter Analysis, even though I couldn't see much ripple. It turns out that if you have a bit of ripple on one side of the peak and a bit on the other side, the entire span of what lies between them is considered ripple. So you have to apply some common sense to the ripple measurement.



Ripple can be precisely defined when you are dealing with mathematical formulas for filter response, but if you are looking at an arbitrarily wiggly response, it is hard to come up with an algorithm that always does what you want. The algorithm used by Filter Analysis is geared toward ripple on relatively flat peaks, with no additional ripple down the sides.



Sam W.

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