Compact Structure for Implementing Elementary Fractional-Order Filter Functions.

A reconfigurable structure for implementing the fundamental fractional-order filter functions, as well as their inverse filter counterparts, is introduced in this work. This is performed by expressing the transfer function of the filter as a ratio of a synthetic impedance, which is approximated by a rational integer-order transfer function implemented by appropriately configured RC network, and an ohmic or capacitive impedance. An offered benefit is that keeping the synthetic impedance constant, the filter functions are implemented through an appropriate selection of the type of the other impedance. The provided simulation results confirm the validity of the presented concept.