Aspects and embodiments relate to a cavity resonator assembly and filters formed from such cavity resonator assemblies. One aspect provides a resonator assembly comprising: a first resonator cavity, a first resonant member, and a first signal feed; a second resonator cavity, a second resonant member, and a second signal feed. The first resonant member is located within the first resonator cavity, arranged to receive a signal from the first signal feed and configured to resonate within the first cavity at a first fundamental frequency. The second resonant member is located within the second resonator cavity, arranged to receive a signal from the second signal feed and configured to resonate within the second cavity at a second fundamental frequency. At least a portion of the second cavity is housed within the first resonant member, and the first resonator cavity surface from which the first resonant member extends is offset from a second resonator cavity surface from which the second resonant member extends. Aspects and embodiments may provide resonator assemblies which offer a reduction in size compared to a typical dual band resonant structure. That is to say, arrangements may be such that limited additional physical space is required for a dual resonant structure compared to a single resonant structure. Aspects and embodiments may provide for increased flexibility and scalability when building filters from resonant structures compared to conventional filtering solutions.

A resonator, a filter, a duplexer, and a multiplexer are disclosed. In an embodiment a resonator includes a resonant cavity casing having a resonant cavity and an open end, a cover covering the open end and being connected to the resonant cavity casing and a resonance tube located inside the resonant cavity. The resonator further includes a tuning rod disposed inside the resonance tube and a dielectric material located in the resonant cavity, wherein the dielectric material is located in a capacitance area formed between a top of the resonance tube and the cover, wherein the tuning rod is rotatable relative to the dielectric material, and wherein surfaces of the tuning rod and the dielectric material face each other and comprise non-circular structures so that an overlapping of the surfaces is changeable to adjust a frequency when the tuning rod is rotated relative to the dielectric material.

A multi-band RF monoblock filter including at least three RF signal filters defined in the monoblock of dielectric material by resonators defined in part by through-holes extending through the block. In one embodiment, two of the RF signal filters are in a co-linear and side-by-side relationship and the third filter is in a parallel and side-by side relationship with one of the two other RF signal filters. A pattern of conductive material defines two end and one interior RF signal input/output on the block top surface. The end RF signal input/outputs are located at opposite ends of the block and the central RF signal input/output is located between the two co-linear and side-by-side RF filters. An RF signal is transmitted through the one end RF signal input/output, the two parallel and side-by-side RF signal filters, and the central RF signal input/output and also through the other end RF signal input/output, one of the co-linear and side-by-side RF filters, and the central RF signal input/output.

The present application is directed to a filter and methods of transmitting a signal through the filter. The filter includes a pair of adjoined blocks of dielectric material. A top surface of each block has a conductive patterned region. The filter also includes plural spaced apart through-holes extending through each block from the top surface to a bottom surface. The through-holes are partially surrounded by the patterned region. The filter also includes a peripheral window disposed between the adjoined blocks to permit a coupling between adjacent through-holes of the adjoined blocks. The filter also includes an in-line window and/or a crenellation located within a block of the pair of blocks and disposed between adjacent through-holes of the block to limit or tune coupling between the adjacent through-holes. The application is also directed to a system including a printed circuit board and a filter.

The present application is directed to an enclosure for hermetically sealing ceramic filters. The enclosure includes a container body with a hollow cavity for receiving electronic components. A container lid is hermetically sealed to the body to maintain a controlled environment. A connector allows for communicating between the electronic components received within the enclosure and other electronic components located outside the enclosure. The enclosure also includes a filter having a block of dielectric material with a top surface including a patterned region, a bottom surface, and side surfaces. A through-hole extends through the block from the top surface to the bottom surface. The through-hole is partially surrounded by the patterned region. A wall extends from the top surface, and has an inner surface, an outer surface, and a roof. The application is also directed to a system including a printed circuit board and a filter provided in the enclosure.

A ceramic monoblock RF filter for the transmission of an RF signal comprising a block of dielectric material including opposed top and bottom surfaces, opposed longitudinal side surfaces, and opposed transverse side surfaces. A plurality of spaced apart through-hole resonators extend through the block and terminate in openings in the top and bottom surfaces of the block. A second plurality of grounded RF signal blocking through-holes extend through the block and terminate in respective openings in the top and bottom surfaces of the block. The grounded through-holes are located and positioned in a relationship off-set and on opposite sides of the first plurality of through-hole resonators for blocking the coupling of the RF signal between RF signal input/outputs and selected ones of the first plurality of resonators and also between non-adjacent ones of the first plurality of resonators.

An input/output apparatus of a multiplexer is provided, including: a main tap and at least two branch taps of the main tap, where each of the at least two branch taps is configured to couple to a different resonant cavity in the multiplexer, and the at least two branch taps include a first branch tap and a second branch tap; a coupling polarity of the first branch tap is opposite to that of the second branch tap; and a coupling calculation frequency of the second branch tap is closest to a coupling calculation frequency of the first branch tap. The input/output apparatus of the multiplexer enables two channels with closest frequencies to use different coupling polarities. Because the coupling polarities are different, signals naturally do not interfere with each other, and signal interference between channels is eliminated in principle. The embodiments of the present disclosure further provide a corresponding multiplexer.

A filter includes a substrate; a signal line formed on the substrate and including an input terminal and an output terminal at either end of the signal line; and a first pair of resonant lines connected between the signal line and a ground portion, wherein the first pair of resonant lines are connected to the signal line at the same point.

A method for servicing a duplexer having a cavity resonator defining an opening covered by an RF plate. The RF plate defines an opening through which a pass-band tuning pipe extends and is secured thereto. A collar is attached to one end of the pipe, and at least one steel set screw extends into the interior of the collar, the at least one end having a soft (e.g., brass) tip. A tuning plunger is slidingly positioned within the pass-band tuning pipe. A rod is attached to a first end of the tuning plunger and extends through the collar, the rod being fabricated from a material harder than the tip of the at least one set screw. The at least one set screw is configured for tightening down on the rod to secure the rod and tuning plunger in place. A trimmer capacitor is positioned in the RF plate.

Methods and devices suitable for monitoring the frequency of microwave tunable filters in real time. The frequency readout relies on the natural response of such a filter when excited by a pulse. Methods of measuring an operating frequency of a pole in a tunable filter include measuring a number of cycles in a natural response in the filter when the filter is excited by an electric current pulse, and determining a resonance frequency based on the number of cycles measured in the natural response. Such a method can provide the operating frequency information in a binary digital format, making it relatively easy to read and process. A measuring resonator may be mounted to the filter resonator and connected by a common actuator.