Digitizing Analog Filters with the Bilinear Transformation

The desirable properties of many filter types (such as lowpass, highpass, and bandpass) are preserved very well by the mapping called the bilinear transform.

---

Subsections

• Bilinear Transformation
• Frequency Warping
• Analog Prototype Filter
• Examples

---

Order a Hardcopy of Introduction to Digital Filters

Previous: Example: Second-Order Butterworth Lowpass
Next: Bilinear Transformation

---

written by Julius Orion Smith III
Julius Smith's background is in electrical engineering (BS Rice 1975, PhD Stanford 1983). He is presently Professor of Music and Associate Professor (by courtesy) of Electrical Engineering at Stanford's Center for Computer Research in Music and Acoustics (CCRMA), teaching courses and pursuing research related to signal processing applied to music and audio systems. See http://ccrma.stanford.edu/~jos/ for details.