An apparatus includes a filter. The filter includes a metal structure forming a cavity and includes a ceramic block, which is suspended in the cavity. The ceramic block has two removed portions, the removed portions removed from two opposing sides of the ceramic block. The ceramic block further has one or more slots that that span a region of ceramic between the two removed portions and connects chambers formed by the two regions with chambers formed by the one or more slots, wherein a combined structure of the ceramic block, cavity, and metal structure supports multiple fundamental TM modes and one fundamental TE mode. The filter comprises multiple coupling structures to couple radio frequency signals into and out of the filter. The apparatus may include multi-cavity filters including one and typically multiple ones of the filters.

An RF filter includes: an electrical conductor defining an outer sphere; a dielectric material defining an inner sphere disposed within the conductor outer sphere; and at least a first electrical probe and a second electrical probe. Each probe extends through the conductor and is electrically insulated from it. A spherical shape of one or both of the inner and outer spheres is interrupted by: a) a first localized discontinuity in said spherical shape disposed along a first axis passing through a geometric center of the one or both of the inner and outer spheres; and b) a second localized discontinuity in said sphere form disposed along a second axis passing through the geometric center, the second axis perpendicular to the first axis. There can be more than these two discontinuities, implemented as chamfers, tuning screws, and the like. Series and parallel coupling of the spheres is detailed.

A non-contact frequency automatic tuning filter with an antileakage chamber includes a first casing with a first cavity formed at a first opening of the first casing, a moving part, and a second cavity. The second cavity has a second casing, a chamber formed in the second casing, and second and third openings penetrating through the second casing. The moving part is plugged from the third opening into the first cavity or from the third opening into a space between the third opening and the first cavity. The second opening proximate to the moving part constitutes a part of the chamber. The second casing has a spacing portion proximate to the moving part for separating the moving part and chamber. The first and second casings are not in contact with the moving part. The invention can prevent leakage of electromagnetic waves and unstable frequency shifting.

This application relates to components of communications devices, and in particular, to a dielectric resonator and a dielectric filter, a transceiver, and a base station to which the dielectric resonator is applied. Embodiments of this application provide a dielectric resonator and a dielectric filter, a transceiver, and a base station to which the dielectric resonator is applied. The dielectric resonator includes a metal cavity and a dielectric block that is disposed in the metal cavity and that is made from a solid-state dielectric material; where sizes of the dielectric block meet c<b<a, where a, b, and c are respectively the sizes of the dielectric block in three dimensions in a three-dimensional coordinate system; a hole is disposed on the dielectric block; and a surface of the dielectric block is not metalized and is not in contact with the metal cavity.

A triple-band bandpass filter with at least one cavity resonator. Each cavity resonator has the same three orthogonal resonances modes corresponding to three unique resonance frequencies. The three unique resonance frequencies define the passbands of the filter. The filter has an input probe coupled to an input cavity resonator. The filter has an output probe coupled to an output cavity resonator. The input and output probes are shaped to concurrently couple signal waveforms in each of the resonance modes. Coupling probes that can be used as input or output probes are also provided. An inter-cavity coupling operable to concurrently transmit signal waveforms in each of the resonance modes is also provided. The inter-cavity coupling can be used to transmit signals between adjacent cavity resonators in the filter.

A radio-frequency filter with at least one dielectric multi-mode resonator is provided. The resonator includes a metal housing with a top surface, a bottom surface, four sectors between the top and bottom surfaces, and including a resonator cavity therein. The resonator further includes a dielectric body positioned inside the cavity, the dielectric body having a first thickness between the top and bottom surfaces of the cavity, wherein there is a gap between the sectors of the housing and the dielectric body, the dielectric body including a hollow on the surface facing the top surface of the housing and on the surface facing the bottom surface of the housing, the dielectric body thus having a second thickness at the location of the hollows, the second thickness being smaller than the first thickness.

A non-contact frequency automatic tuning filter with an antileakage chamber includes a first casing with a first cavity formed at a first opening of the first casing, a moving part, and a second cavity. The second cavity has a second casing, a chamber formed in the second casing, and second and third openings penetrating through the second casing. The moving part is plugged from the third opening into the first cavity or from the third opening into a space between the third opening and the first cavity. The second opening proximate to the moving part constitutes a part of the chamber. The second casing has a spacing portion proximate to the moving part for separating the moving part and chamber. The first and second casings are not in contact with the moving part. The invention can prevent leakage of electromagnetic waves and unstable frequency shifting.

Waveguides in accordance with embodiments of the invention are disclosed. In one embodiment, a dual-mode circular waveguide includes a cavity, a first end wall including a first handedness-preserving metasurface positioned at a first end of the cavity, and a second end wall including a second handedness-preserving metasurface positioned at a second end of the cavity.

The present application provides a dielectric filter, including a body part, a dielectric resonator, a cavity is formed in the body part, and a support kit is disposed at a bottom of the cavity. The dielectric resonator, including a dielectric body and at least two adjusting holes disposed on the dielectric body, is contained in the cavity and is disposed on the support kit. The dielectric body has a first mirror plane and a second mirror plane, which are perpendicular to each other and penetrate through the top plane and the bottom plane of the dielectric body, and any two of the at least two adjusting holes are not mirror symmetric relative to the first mirror plane or the second mirror plane.

A multi-mode waveguide is provided, the waveguide configured to support at least two degenerate modes of electromagnetic fields. The waveguide comprises an input node configured to couple electromagnetic fields into the waveguide. An output node is configured to couple electromagnetic fields out of the waveguide. A perturbation is configured to couple the two degenerate modes within the waveguide. The input node and the output node are positioned such that coupled degenerate modes clockwise and counter-clockwise propagating waves within the waveguide with at least two transmission minima. A waveguide device comprising a plurality of such multi-mode waveguides is also provided, the waveguide device having a plurality of transmission minima.