The present invention is a tunable bandpass filter to provide a constant absolute bandwidth across a tuning range, comprising of a pair of resonators to determine a filter center frequency, each said resonator has a rectangular waveguide cavity, wherein said filter center frequency depends on the dimensions of said rectangular waveguide cavity; a pair of side walls attached to said pair of resonators to form a filter housing; a tuning element movably attached to at least one of said pair of side walls and extending in said filter housing and movable orthogonally to said pair of resonators, and wherein said dimensions of said rectangular waveguide cavity change by moving said tuning element, thereby said filter center frequency is changed.

A waveguide filter includes a fundamental waveguide unit. The fundamental waveguide unit may have an irregular hexagonal metal structure. One wall of the irregular hexagonal metal structure may form a connection to one or more walls of another fundamental waveguide unit having an irregular hexagonal metal structure. A fundamental waveguide unit may include a hollow irregular hexagonal metal structure which includes a resonant cavity that receives an electromagnetic signal and propagates the signal through the resonant cavity.

Example dielectric filters, transceiver devices, and base stations are described. One example dielectric filter includes a dielectric block whose surface is covered with a metal layer, where the dielectric block includes at least two resonant cavities. The dielectric block is provided with a via hole, the via hole is located between two adjacent resonant cavities, and an inner wall of the via hole is covered with a metal layer. A first partition ring is disposed on the surface of the dielectric block and is surrounding at least one opening of the via hole, and the dielectric block is exposed in an area enclosed by an inner edge of the first partition ring and an outer edge of the first partition ring.

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.

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.

The invention relates to a method of manufacturing a dielectric filter. The method comprises the steps of: (a) preparing a ceramic substrate; (b) applying a conductive paste on the ceramic substrate, wherein the conductive paste comprises, (i) 100 parts by weight of a conductive powder, (ii) 0.1 to 10.0 parts by weight of a glass frit comprising silicon oxide, boron oxide, aluminum oxide and an alkaline metal oxide, and (iii) an organic vehicle; and (c) firing the applied conductive paste.

The present disclosure presents a dual-channel filter based on a dielectric resonator, which includes a metal cavity, a dielectric resonator, two tuning metal probes, and four feeding metal probes. The dielectric resonator is disposed at the center of the metal cavity. The four feeding metal probes are disposed around the metal cavity, and coupled to the dielectric resonator. The two tuning metal probes are connected to the metal cavity, and respectively located at a central position directly above and below the dielectric resonator. The dual-channel filter integrates two channel filters with good isolation between them, and has two input ports and two output ports.

The present disclosure relates to a filter for filtering wavelengths of an electromagnetic signal to provide a filtered signal. The filter includes: at least one commensurate-line structure (CLS); and, at least one stub-modified commensurate-line structure (SMCLS) arranged to provide a corresponding at least one transmission zero in the filtered signal.

The present disclosure relates to a filter for filtering wavelengths of an electromagnetic signal to provide a filtered signal. The filter includes: at least one commensurate-line structure (CLS); and, at least one stub-modified commensurate-line structure (SMCLS) arranged to provide a corresponding at least one transmission zero in the filtered signal.

This application provides a dielectric resonator, including a dielectric body disposed in a hollow conductive housing, where the dielectric body includes a first end face and a second end face that are disposed opposite to each other and a circumferential surface connected between the first end face and the second end face. The first end face is provided with a first groove, the second end face is provided with a second groove, the first end face and the second end face are in contact with an inner wall of the conductive housing, and extension directions of the first groove and the second groove are different. This application further provides a filter. This application can implement single-sided installation of the dielectric resonator, so that an objective of miniaturization is achieved and assembly becomes easy. In addition, coupling between resonance modes can be enhanced because the extension directions of the first groove and the second groove are different.