Bessel filter

Started by ddeneef February 6, 2002

I need to use a 5th order Bessel filter in Simulink, and I found
the "analog filter design" block in the DSP Blockset menu. This
block uses the "besself" function to perform this operation.
But with this function I don't have an attenuation of -3 dB at the
cutoff frequency : the attenuation at Wn increases when the filter
order increases.
How can I correct this in order to have -3 dB at the cutoff
frequency ?

Thank you for your help !