In filters usually you can find two different specifications: number of poles and dB/octave.(adsbygoogle = window.adsbygoogle || []).push({});

I know that the poles gives you the transfer functions using this equation for a low pass filter

[tex]H(f)=1/\sqrt{1+(f/f_{C})^{2P}}[/tex]

Where P is the number of poles of the filter. But how can I translate this into the dB/octave. I suppose that there is a rule of thumb but I cannot find it. Can anybody indicate to me this rule or give a reference where I could find it?

Thanks in advance

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# Filter specifications, conversion between them

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