ACTIVE FILTER NETWORKS

摘要

A band-pass filter consists of a number of circuits resistively coupled together to form a ladder network between an input and an output. Each circuit includes a positive impedance converter terminated so as to provide an impedance inversely proportional to the square of the complex frequency, prefer-ably a capacitatively-terminated positive impedance converter is used wherein the impedance conversion ratio is proportional to the complex frequency. The in-put and output of the filter are resistively terminated such that all reactive elements of the filter are contained with the said circuits. Preferably the capacitors all have the same capacitance value.