Apparatuses, methods of assembling a resonator, and methods of tuning a resonator are provided. An example apparatus may include at least one resonator comprising a resonator hole defined within the resonator and defining an inner wall of the at least one resonator, a tuning cover comprising at least one hollow rod, and a tuning element comprising a bottom flanged portion. The tuning element may be configured to be inserted into the at least one hollow rod and the bottom flanged portion is configured to cover at least a bottom portion of the hollow rod. The bottom flanged portion of the tuning element is configured to be positioned between the at least one hollow rod and the inner wall of the at least one resonator.

A cavity-type radio frequency filter is disclosed. the radio frequency filter having a cavity structure including an enclosure, a resonant element, a cover, a frequency tuning screw, and a resilient fixing member. The enclosure has a hollow inside and an open surface on one side to have a cavity. The resonant element is positioned in the hollow of the enclosure. The cover has a screw hole having a preset diameter at a position corresponding to the resonant element, and is configured to seal the open surface of the enclosure. The frequency tuning screw is configured to be screwed into the screw hole of the cover, and it has an upper end formed at least partially with a latching abutment that protrudes outwardly.

Adaptive RF filters based on modulated resonators are provided. The filter architecture is based on time-interleaved commutation of passive RF resonators. The architecture can behave as a two-port filter network, with a fully tunable instantaneous filter bandwidth. The filters are applicable as miniaturized, environment-aware RF signal processing components and can be used in mobile communications.

An in-line resonator filter has a linear array of three or more conductors. A first pair of adjacent conductors has inductive main coupling and oppositely signed capacitive main coupling, while a second pair of non-adjacent conductors has inductive cross-coupling. The first and second pairs have one conductor in common. Between the second pair of non-adjacent conductors, there is no direct ohmic connection that provides the corresponding inductive cross-coupling. The oppositely signed capacitive main coupling compensates for at least a portion of the inductive main coupling between the first pair of adjacent conductors. The in-line resonator filter is able to provide one or more transmission zeros without requiring any discrete bypass connectors that provide direct ohmic connection between pairs of non-adjacent conductors. As such, the in-line resonator filters can be smaller, less complex, and less susceptible to damage.

A ceramic resonator radio frequency filter includes a printed circuit board, one or more first coaxial resonators disposed on the printed circuit board, and one or more second coaxial resonators disposed over the one or more first coaxial resonators so that the one or more first coaxial resonators and one or more second coaxial resonators are arranged in a stacked configuration. The one or more first coaxial resonators and second coaxial resonators electrically connected to the printed circuit board.

The present disclosure relates to a radio frequency filter having a cavity structure, and including a housing having internally a hollow space and an open side to provide at least one cavity, at least one resonance element located in the hollow space of the housing, a cover configured to have at least one groove which is internally threaded, recessed at a predetermined diameter and depth at a position corresponding to the resonance element, and has a bottom portion that is thinner than other portions, and to close the open side of the housing, and at least one frequency tuning screw configured to threadedly mate with the groove of the cover. When the frequency tuning screw threadedly mates with the groove, a bottom surface of the groove is depressed by the frequency tuning screw toward the resonant element.

A tunable probe includes a first resonator, a second resonator spaced from the first resonator, and a cross-couple extending from the first resonator to the second resonator. The cross-couple includes a first substrate and a second substrate disposed between the first and second resonator to create a capacitance between the first and second resonators. The cross-couple further includes a wire connecting the first and second substrates and a dielectric surrounding the wire.

A multi-mode resonator includes: a housing having a cavity therein; and a plurality of resonance ribs which are arranged radially around a center of the cavity with a predetermined interval therebetween. Each of the plurality of resonance ribs includes a body having a lower end and an upper end. The lower end of each of the plurality of resonance ribs is fixed to a bottom surface of the housing, and the body of the each of the plurality of resonance ribs is bent so that the upper end of each of the plurality of resonance ribs points to the center of the cavity.

The present disclosure relates to a coupling structure of a filter. One example coupling structure of the filter includes at least two resonant cavities. Each resonant cavity includes an internal space surrounded by a resonant cavity wall, a resonant cavity bottom plate, and a resonant cavity lid. The at least two resonant cavities are sequentially connected. Each resonant cavity of the at least two resonant cavities includes one resonator. A coupling rib assembly is between every two resonant cavities of the at least two resonant cavities. The coupling rib assembly includes a first coupling rib and a second coupling rib, where the first coupling rib is connected to the resonant cavity wall and the resonant cavity bottom plate to block two adjacent resonant cavities from each other, and the second coupling rib is connected to the resonant cavity bottom plate and intersects with the first coupling rib.

The present invention is a high Q tunable co-axial filter, which maintains a constant absolute bandwidth and a constant Q over the tuning range. The present filter can be tuned by a single rotational mechanism irrespective of the filter order. A plurality of tunable resonators is aligned on a common filter axis. Each resonator has a casing having an inner wall and a cavity. The resonators are coupled by an iris opening. A pair of end plates completes the filter casing. A rotating rod placed on the common axis of the resonated, that has a tuning post attached to it, and each post located in each resonator, is used to tune the filter.