ACTIVE FILTER WITH DUAL RESPONSE

摘要

Based on an active low-pass filter structure comprising a main conductor line between an input port and an output port, consisting of an input conductor section, an output conductor section, and an inductance network in series between the input and output sections, the inductance network being coupled to the LC resonators, an LC resonator connected to each junction point between two network inductances, and at least one negative resistance in series with one of the resonators, a dual response filter is formed by providing an auxiliary conductor line, wherein an input end of the filter is connected to an electrical ground, forming a resonator with its own resonant frequency less than the cut-off frequency fc of the low-pass filter, the auxiliary line extending from this end along and away from the main line. The resonator forms by coupling a rejection filter around the resonant frequency within the bandwidth in the low-pass filter.

主权项

1. Active filter with dual response, comprising a main conductive line between an input port and an output port, including an input conductive section, an output conductive section, and an inductance network in series between the input and output conductive sections, the inductance network being coupled to the LC resonators, an LC resonator connected to each junction point between two network inductances, and at least one negative resistance in series with one of the resonators, the main line, the LC resonators and the negative resistances forming an active low-pass filter with a cut-off frequency fc, wherein the filter comprises a conductive auxiliary line, having one end at the filter input side is connected to an electrical ground, and forming a resonator with a resonant frequency fr less than the cut-off frequency fc of the low-pass filter, the auxiliary line extending from said end, along and being away from the main line, and forming by coupling a rejection filter around the said resonant frequency in the low-pass filter bandwidth.