Abstract: A resonant cavity filter includes a filter housing defining an internal cavity therein, a resonating element in the internal cavity of the filter housing, and a coupling transmission line extending adjacent a periphery of the resonating element in the internal cavity of the filter housing. The resonating element is rotatable relative to the coupling transmission line to vary an electromagnetic coupling therebetween. Related devices and methods of operation are also discussed.

Abstract: Filters include a housing having an input port and an output port and a plurality of resonant cavities within the housing. Each resonant cavity may include a respective notch resonator. The filter may further include a bandpass filter that includes a plurality of bandpass resonators, the bandpass filter extending between the input port and the output port. The bandpass filter may replace a transmission line that is included in conventional filters.

Abstract: Radio frequency (RF) switches are provided. An RF switch includes a first RF transmission line and a second RF transmission line that are capacitively coupled to each other. Moreover, the RF switch includes a third RF transmission line having a signal trace that is electrically isolated from the first and second RF transmission lines. Related methods of operating filter devices are also provided.

Abstract: Radio frequency (RF) switches are provided. An RF switch includes a first RF transmission line and a second RF transmission line that are capacitively coupled to each other. Moreover, the RF switch includes a third RF transmission line having a signal trace that is electrically isolated from the first and second RF transmission lines. Related methods of operating filter devices are also provided.

Abstract: Filters include a housing having an input port and an output port and a plurality of resonant cavities within the housing. Each resonant cavity may include a respective notch resonator. The filter may further include a bandpass filter that includes a plurality of bandpass resonators, the bandpass filter extending between the input port and the output port. The bandpass filter may replace a transmission line that is included in conventional filters.

Abstract: A resonant cavity filter includes a filter housing defining an internal cavity therein, a resonating element in the internal cavity of the filter housing, and a coupling transmission line extending adjacent a periphery of the resonating element in the internal cavity of the filter housing. The resonating element is rotatable relative to the coupling transmission line to vary an electromagnetic coupling therebetween. Related devices and methods of operation are also discussed.

Abstract: Filter devices that include a movable radio frequency (RF) transmission line are provided. A filter device that includes a movable RF transmission line also includes a plurality of resonators. The movable RF transmission line is configured to move between a first position and a second position relative to the resonators. Electromagnetic coupling between the movable RF transmission line and the resonators is reduced at the second position relative to the first position. Related methods of operating filter devices are also provided.

Abstract: In-line filters may include a tubular metallic housing defining a single inner cavity that extends along a longitudinal axis and a plurality of resonators that are spaced apart along the longitudinal axis within the single inner cavity, each resonator having a stalk. The stalks of first and second of the resonators that are adjacent each other are rotated to have different angular orientations.

Abstract: In-line filters may include a tubular metallic housing defining a single inner cavity that extends along a longitudinal axis and a plurality of resonators that are spaced apart along the longitudinal axis within the single inner cavity, each resonator having a stalk. The stalks of first and second of the resonators that are adjacent each other are rotated to have different angular orientations.

Abstract: The present invention provides filter assemblies, tuning elements and a method of tuning a filter. A filter assembly includes a housing having a top cover, a bottom cover and at least one sidewall, the top cover, the bottom cover and the at least one sidewall defining an internal cavity, the housing configured to receive first through third radio frequency (“RF”) transmission lines; a top metal sheet mounted within the internal cavity that has a plurality of openings that form a first hole pattern; and a bottom metal sheet mounted within the internal cavity that has a plurality of openings that form a second hole pattern. The top and bottom metal sheets are vertically spaced-apart from each other in a vertically stacked relationship within the internal cavity. The top metal sheet and the bottom metal sheet each include at least one resonator.

Abstract: In-line filters may include a tubular metallic housing defining a single inner cavity that extends along a longitudinal axis and a plurality of resonators that are spaced apart along the longitudinal axis within the single inner cavity, each resonator having a stalk. The stalks of first and second of the resonators that are adjacent each other are rotated to have different angular orientations.

Abstract: The present invention provides filter assemblies, tuning elements and a method of tuning a filter. A filter assembly includes a housing having a top cover, a bottom cover and at least one sidewall, the top cover, the bottom cover and the at least one sidewall defining an internal cavity, the housing configured to receive first through third radio frequency (“RF”) transmission lines; a top metal sheet mounted within the internal cavity that has a plurality of openings that form a first hole pattern; and a bottom metal sheet mounted within the internal cavity that has a plurality of openings that form a second hole pattern. The top and bottom metal sheets are vertically spaced-apart from each other in a vertically stacked relationship within the internal cavity. The top metal sheet and the bottom metal sheet each include at least one resonator.

Abstract: The present invention provides filter assemblies, tuning elements and a method of tuning a filter. A filter assembly includes a housing having a top cover, a bottom cover and at least one sidewall, the top cover, the bottom cover and the at least one sidewall defining an internal cavity, the housing configured to receive first through third radio frequency (“RF”) transmission lines; a top metal sheet mounted within the internal cavity that has a plurality of openings that form a first hole pattern; and a bottom metal sheet mounted within the internal cavity that has a plurality of openings that form a second hole pattern. The top and bottom metal sheets are vertically spaced-apart from each other in a vertically stacked relationship within the internal cavity. The top metal sheet and the bottom metal sheet each include at least one resonator.

Abstract: In-line filters may include a tubular metallic housing defining a single inner cavity that extends along a longitudinal axis and a plurality of resonators that are spaced apart along the longitudinal axis within the single inner cavity, each resonator having a stalk. The stalks of first and second of the resonators that are adjacent each other are rotated to have different angular orientations.

Abstract: A method for compensating a temperature drift of a microwave filter comprises: measuring a first frequency response of a microwave filter at a first temperature; determining values of elements of an equivalent circuit corresponding to the microwave filter such that a first modelled frequency response computed using the equivalent circuit matches the first measured frequency response to obtain a first model modelling the microwave filter at the first temperature: measuring a second frequency response of the microwave filter at a second temperature; determining values of elements of the equivalent circuit corresponding to the microwave filter anew such that a second modelled frequency response computed using the equivalent circuit matches the second measured frequency response to obtain a second model modelling the microwave filter at the second temperature; and adjusting an overall temperature drift of the microwave filter to adjust the temperature drifts of the resonant filter elements.

Abstract: A microwave filter comprises at least one resonant filter element resonating at a resonant frequency and having a housing, a resonant filter cavity arranged in the housing and a resonator element arranged in the housing. At least two tuning elements are arranged on the housing of the resonant filter element and each extend into the cavity with a shaft portion, wherein the two tuning elements are movable with respect to the housing to adjust the length of the shaft portion extending into the housing and wherein the at least two tuning elements are constituted and designed such that by adjusting the length of the shaft portion of each tuning element extending into the housing a temperature drift of the resonant frequency is adjustable.

Abstract: The present invention provides filter assemblies, tuning elements and a method of tuning a filter. A filter assembly includes a housing having a top cover, a bottom cover and at least one sidewall, the top cover, the bottom cover and the at least one sidewall defining an internal cavity, the housing configured to receive first through third radio frequency (“RF”) transmission lines; a top metal sheet mounted within the internal cavity that has a plurality of openings that form a first hole pattern; and a bottom metal sheet mounted within the internal cavity that has a plurality of openings that form a second hole pattern. The top and bottom metal sheets are vertically spaced-apart from each other in a vertically stacked relationship within the internal cavity. The top metal sheet and the bottom metal sheet each include at least one resonator.

Abstract: The present invention provides filter assemblies, tuning elements and a method of tuning a filter. A filter assembly includes a housing having a top cover, a bottom cover and at least one sidewall, the top cover, the bottom cover and the at least one sidewall defining an internal cavity, the housing configured to receive first through third radio frequency (“RF”) transmission lines; a top metal sheet mounted within the internal cavity that has a plurality of openings that form a first hole pattern; and a bottom metal sheet mounted within the internal cavity that has a plurality of openings that form a second hole pattern. The top and bottom metal sheets are vertically spaced-apart from each other in a vertically stacked relationship within the internal cavity. The top metal sheet and the bottom metal sheet each include at least one resonator.

Abstract: A method for compensating a temperature drift of a microwave filter comprises: measuring a first frequency response of a microwave filter at a first temperature; determining values of elements of an equivalent circuit corresponding to the microwave filter such that a first modelled frequency response computed using the equivalent circuit matches the first measured frequency response to obtain a first model modelling the microwave filter at the first temperature: measuring a second frequency response of the microwave filter at a second temperature; determining values of elements of the equivalent circuit corresponding to the microwave filter anew such that a second modelled frequency response computed using the equivalent circuit matches the second measured frequency response to obtain a second model modelling the microwave filter at the second temperature; and adjusting an overall temperature drift of the microwave filter to adjust the temperature drifts of the resonant filter elements.

Abstract: A microwave filter comprises at least one resonant filter element resonating at a resonant frequency and having a housing, a resonant filter cavity arranged in the housing and a resonator element arranged in the housing. At least two tuning elements are arranged on the housing of the resonant filter element and each extend into the cavity with a shaft portion, wherein the two tuning elements are movable with respect to the housing to adjust the length of the shaft portion extending into the housing and wherein the at least two tuning elements are constituted and designed such that by adjusting the length of the shaft portion of each tuning element extending into the housing a temperature drift of the resonant frequency is adjustable.