FOURTH-ORDER NOTCH FILTER Russian patent published in 2021 - IPC H03H11/12 

FIELD: radio engineering.

SUBSTANCE: invention relates to the field of radio engineering, it can be used, for example, to filter interference and protect radio monitoring systems in the short-wave range. The filter contains device input (1) connected to signal source (2), device output (3) connected to load (4), the second-order input notch filter with first (5) and second (6) inputs, as well as main output (7), first operational amplifier (8), first resistor (9), second resistor (10), second operational amplifier (11), third resistor (12), common bus of power source (13), first capacitor (14), third operational amplifier (15), fourth (16), fifth (17), sixth (18) resistors, second capacitor (20), fourth operational amplifier (19), seventh (21), eighth (22), ninth (23), tenth (24) resistors, and eleventh resistor (25). Signal source (2), and load (4) are coordinated with common bus of power source (13). Output notch filter (26) is introduced into the device circuit, identical to the input notch filter in terms of the composition of the elements, the connections between them and the functional purpose of the inputs and outputs, as well as additional non-inverting amplifier (30). The input of second-order output notch filter (26) is coordinated with common bus of power source (13). The output of additional non-inverting amplifier (30) is connected to second input (6) of the second-order input notch filter.

EFFECT: technical result is that in the fourth-order notch filter, it is possible to adjust the delay band.

3 cl, 6 dwg