MICROWAVE FILTER Russian patent published in 2000 - IPC

FIELD: frequency-selective circuits of radio electronic equipment. SUBSTANCE: microwave filter has input and output transmission lines coupled with N resonators; inputs of each of N resonators, where N > 2, are coupled with input transmission line and output of each of N resonators is coupled with output transmission line; all resonators are electrically interconnected in series. Microwave filter may be physically built around microstrip, strip, and waveguide lines. In case of in-phase coupling between resonators and input and output lines, their lengths are multiples of half the respective resonant wavelengths nλ₁/2 and kλ₂/2, where λ₁ and λ₂ are lengths of respective resonant waves, n and k are numbers of natural number series that differ by (2m - 1), where m - number of natural number series, but in case resonators are coupled with output transmission line in phase opposition and input transmission line are coupled in-phase , their lengths are multiples of half the respective resonant wavelengths nλ₁/2 and kλ₂/2, where λ₁ and λ₂ - are lengths of respective resonant wavelengths, n and k are numbers of natural number series that differ by (2m - 2), where m is number of natural number series. Provision is made to reduce loss of useful signal brought in working passband and to obtain amplitude- frequency response pole. EFFECT: reduced size, low loss of useful signal, and high linearity of phase-frequency response in passband. 8 cl, 26 dwg