A broadband, dual-polarized, cavity-backed slot antenna (CBSA) array is presented for enabling full-duplex wireless communication. The antenna consists of a thin rectangular cavity appropriately loaded with metallic septa to excite multiple resonances of similar desired field distribution to achieve consistent radiation characteristics over a wide bandwidth. Four pairs of orthogonal radiating slots are cut out on one of the broad-walls of the cavity; all of which are fed by two orthogonal slots on the opposite broad-wall of the cavity. The cavity is fed by an end-launch coaxial-to-waveguide transition to excite one of the channels. The other channel is excited by a two-pronged microstrip line symmetrically crossing over the other cavity feeding slot. Due to the out-of-phase coupling from the two prongs of the microstrip line to the other port, this type of excitation is shown to provide an unpredicted level of isolation between the two channels over a wide bandwidth.

A dual-mode dielectric resonator using two dissimilar modes is described, the dissimilar modes supported by a ridge waveguide resonator and a ¼-wavelength (¼λ) metalized cylindrical resonator within a single, metal-coated dielectric block. Each ridge waveguide resonator and cylindrical resonator form a dual-mode resonator pair. Coupling control posts set between the ridge waveguide resonator and cylindrical resonator can adjust their coupling. Multiple pairs of ridge waveguide/cylindrical resonators are fabricated in the same dielectric block to form a coupled resonator bandpass filter, including an 8-pole or 10-pole dielectric resonator filter, for 5G or other applications. Transmission zeros can be introduced by a metalized blind hole extending vertically between two ridge waveguide resonators or a microstrip extending between two dual-mode resonator pairs between which there exists no partial-width or full-width dielectric window.

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.

In examples, systems and methods for waveguide antenna arrays with integrated filters are described. An example waveguide antenna array element a waveguide section has a first end and second end. The waveguide section is configured to propagate electromagnetic energy. The waveguide antenna array element also includes a feed configured to launch an electromagnetic wave into the first end of the waveguide section. The waveguide antenna array element also includes a waveguide filter having at least one waveguide cavity coupled to the second end of the waveguide section. The waveguide filter is configured to pass a first set of electromagnetic frequencies and reject a second set of electromagnetic frequencies. Yet further, the waveguide antenna array element includes an antenna coupled to the waveguide filter configured to radiate a portion of the electromagnetic energy passed by the waveguide filter.

A broadband, dual-polarized, cavity-backed slot antenna (CBSA) array is presented for enabling full-duplex wireless communication. The antenna consists of a thin rectangular cavity appropriately loaded with metallic septa to excite multiple resonances of similar desired field distribution to achieve consistent radiation characteristics over a wide bandwidth. Four pairs of orthogonal radiating slots are cut out on one of the broad-walls of the cavity; all of which are fed by two orthogonal slots on the opposite broad-wall of the cavity. The cavity is fed by an end-launch coaxial-to-waveguide transition to excite one of the channels. The other channel is excited by a two-pronged microstrip line symmetrically crossing over the other cavity feeding slot. Due to the out-of-phase coupling from the two prongs of the microstrip line to the other port, this type of excitation is shown to provide an unpredicted level of isolation between the two channels over a wide bandwidth.

A bandpass filter has a plurality of resonant cavities. The plurality of resonant cavities are arranged into a sequence of adjacent resonant cavities. Each resonant cavity is configured to define the same fundamental resonant frequency. The filter includes a plurality of coupling irises, with one of the coupling irises positioned between each pair of adjacent resonant cavities. Each resonant cavity includes a plurality of cavity sections. Each resonant cavity includes a capacitive iris positioned coupling the cavity sections to one another. The frequency of secondary resonance modes varies amongst the resonant cavities in the plurality of resonant cavities.

A resonator includes a housing having a cavity therein; a plurality of resonance plates which are arranged radially around a center of the cavity with a predetermined interval therebetween; and a plurality of legs each of which supports one of the plurality of resonance plates, respectively. A center of each of the plurality of legs is deviated from a center of a corresponding resonance plate.

In examples, systems and methods for waveguide antenna arrays with integrated filters are described. An example waveguide antenna array element a waveguide section has a first end and second end. The waveguide section is configured to propagate electromagnetic energy. The waveguide antenna array element also includes a feed configured to launch an electromagnetic wave into the first end of the waveguide section. The waveguide antenna array element also includes a waveguide filter having at least one waveguide cavity coupled to the second end of the waveguide section. The waveguide filter is configured to pass a first set of electromagnetic frequencies and reject a second set of electromagnetic frequencies. Yet further, the waveguide antenna array element includes an antenna coupled to the waveguide filter configured to radiate a portion of the electromagnetic energy passed by the waveguide filter.

Disclosed is a multimode microwave filter including a resonator in which a cavity is formed to generate a resonant mode and a plurality of irises formed on a side surface of the resonator, in which the cavity of the resonator has a rhombus-shaped cross section.

A resonator includes a housing having a cavity therein; a plurality of resonance plates which are arranged radially around a center of the cavity with a predetermined interval therebetween; and a plurality of legs each of which supports one of the plurality of resonance plates, respectively. A center of each of the plurality of legs is deviated from a center of a corresponding resonance plate.