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| Passband cutoff frequency:This parameter defines the bandwidth of the analysis. In this example, we have
chosen a bandwidth of 20kHz. This means that we will be able to analyze signals in the DC to 20kHz range.
(This covers most audio and vibration applications.)
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| Passband ripple: This example shows several dB of ripple, which is larger than you would normally want
in a high-quality front end. The ripple in the passband degrades the amplitude accuracy spec. To reduce this
ripple (all other things being equal) we would need to use a larger order filter.
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| Stopband rejection: About -80dB in this example. More is better. Dynamic range can never be better
than the amount of stopband rejection.
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| Efficiency: The 3rd and last important parameter relates to how steeply the response transitions from
the pass band to the stop band. Usually specified in terms of roll-off in dB/octave or dB/decade. A more
useful way of specifying this parameter I will call "efficiency".
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