Design of Higher-Order Fractional Filters With Fully Controllable Frequency Characteristics

Abstract

Higher-order fractional filters with fully controllable frequency characteristics are realized in this work, after fitting the filter’s magnitude response data using a minimum-phase state-space model. Subsequently, rational integer-order transfer functions are derived and implemented using as active elements: a) Operational Transconductance Amplifiers (OTAs) and b) a Field Programmable Analog Array (FPAA) device. The realized filters enjoy electronic adjustability of their type, order, and characteristic frequencies while being easily validated on the digitally programmable FPAA platform.

Keywords

• Fractional-order filters
• approximation techniques
• Butterworth filters
• Chebyshev filters
• operational transconductance amplifiers
• field programmable analog arrays