relation between cuttoff frequency and damping ratio of a second order transfer function(filter) and pt by pt butterworth highpass filter

[Chaudhery]

Hi

I am working on a flight simulator. I have to use a PtbyPt butterworth highpass filter. What i have studied in literature is a second order filter in s domain with a cuttoff frequency W and a damping ratio z. I want to implement this second order filter using pt by pt butterworth filter VI but it demends a low cuttoff and a high cuttoff frequency whereas I have W and z. How can I relate high and low cuttoff frequencies to W and z of 2nd order transfer function.

[nyc_(is_out_of_here)]

---

@Chaudhery wrote:

Hi

I am working on a flight simulator. I have to use a PtbyPt butterworth highpass filter. What i have studied in literature is a second order filter in s domain with a cuttoff frequency W and a damping ratio z. I want to implement this second order filter using pt by pt butterworth filter VI but it demends a low cuttoff and a high cuttoff frequency whereas I have W and z. How can I relate high and low cuttoff frequencies to W and z of 2nd order transfer function.

---

And this is related to LabVIEW how????

[Chaudhery]

I am using labview for implementation and Pt by Pt filter vi for filtering.

[johnsold]

A high pass filter does not have low and high cutoff frequencies.  The Butterworth type filter has a specified transfer function so you do not have control the damping. You can only set the cutoff frequency and the order of the filter.

Most books of filter theory have the equations, plots of frequency response, and transfer functions.

Please post your design equations or a link to the reference where you obtained them and why you think the Butterworth filter is the correct filter for your project.

Lynn