Patent ID: 9647306
Date: 2017-05-09
CPC Classifications: H01P

Claim:
1. A radio-frequency (RF) filter, comprising: a first coaxial resonator in a first orientation and having an input tab on a first side of the filter defined by N coaxial resonators; an N-th coaxial resonator in the first orientation and having an output tab on the first side of the filter; a second coaxial resonator in a second orientation opposite the first orientation so as to form a first interdigitation with the first coaxial resonator; an (N−1)th coaxial resonator in the second orientation so as to form a second interdigitation with the N-th coaxial resonator; at least two coaxial resonators in the first orientation and coupled between the second and (N−1)th coaxial resonators; the N coaxial resonators configured to provide slot coupling between adjacent ones of the N coaxial resonators, the first and second interdigitations configured to provide enhancement of the slot coupling between the first and second coaxial resonators and between the (N−1)th and N-th coaxial resonators.