Hi, 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 ! David |