Design of bandpass filter with Yulewalk

Hello, i am trying to implement the filter attached in the picture but i cannot get the correct result (as seen in the other picture) as the Yulewalk function does not accept negative magnitudes. Can someone please help me?

Answer 1

[Wayne King]

yulewalk() accepts magnitudes so you cannot use negative values. However, it looks like you have specifications in dB so small positive values (magnitudes) end up as negative values. You just need to convert the dB values to magnitudes.

Use db2mag() to convert your dB values to magnitudes and then use those as input to yulewalk()

Answer 2

[George Lazaridis]

ok, i did it with db2mag() and i get this. Which frequency bands should i specify? i specify the following: freq = [0 1 2 12 16 30 Fs/2]*2/Fs. Maybe this is wrong? Because the slope after 16 is not as steep as i want it to be...