The present application discloses embodiments that relate to an electromagnetic apparatus. In one aspect, the present apparatus includes a circuit board configured to propagate an electromagnetic signal. The apparatus also includes a waveguide configured to propagate an electromagnetic signal. The apparatus further includes a coupling port configured to couple a signal between the circuit board and the waveguide, where the coupling port has dimensions based on a desired impedance of the port.

According to various embodiments, a quadrature hybrid coupler included as part of a phase shifter is used to provide variable phase shift to an input signal. The quadrature hybrid coupler includes an input port, an output port, and two terminated ports. The phase shifter includes one or more static lumped elements connected to the QHC to reduce at least one electrical dimension of the QHC to substantially less than a quarter wavelength. The phase shifter also include one or more variable lumped elements connected to the QHC to provide a variable phase shift to the input signal between the input port and the output port of the QHC.

This invention refers to hybrid coupler with the sum port and difference port located on the same side. The hybrid coupler can be efficiently integrated into the high frequency circuit with its simple structure, using common material. To achieve this purpose, the hybrid coupler in this invention consists of the following parts: sum port, difference port, output port 1, output port 2, connection line 1, connection line 2 and microstrip line.

An electronic switch for switching between signal outputs comprises a 6-way symmetric hybrid ring combiner. Each port within the 6-way symmetric hybrid ring combiner is positioned at /4 wavelength increments around a circumference of the 6-way symmetric hybrid ring combiner.

A magnet-less multi-port ring combiner comprises a set of ports extending from the circumference of the magnet-less multi-port ring combiner. The set of ports are positioned at increments around the circumference of the magnet-less multi-port ring combiner. The set of ports comprise a first input port configured to receive a first input signal and a second input port configured to receive a second input signal, wherein the first input signal is 180 out-of-phase with the second input signal. The N-way magnet-less multi-port combiner comprises more than four ports.

A feeding network of a dual-beam antenna and a dual-beam antenna are disclosed. The feeding network includes: a cavity, including an upper grounding metal plate and a lower grounding metal plate; a printed circuit board PCB, disposed inside the cavity, where a splitting network circuit and a phase-shift circuit in the feeding network are integrated into the PCB, and arrangement of the PCB and the cavity enables a wire on the PCB to have a strip line structure as a whole; and at least two radio-frequency signal input ports, where the at least two radio-frequency signal input ports are connected to the splitting network circuit on the PCB.

A feeding network of a dual-beam antenna and a dual-beam antenna are disclosed. The feeding network includes: a cavity, including an upper grounding metal plate and a lower grounding metal plate; a printed circuit board PCB, disposed inside the cavity, where a splitting network circuit and a phase-shift circuit in the feeding network are integrated into the PCB, and arrangement of the PCB and the cavity enables a wire on the PCB to have a strip line structure as a whole; and at least two radio-frequency signal input ports, where the at least two radio-frequency signal input ports are connected to the splitting network circuit on the PCB.

A device and a method for creating and/or maintaining an obstruction free upper respiratory passages. The device is configured to fit under the chin of a subject adjacent to the subject's neck at an external location corresponding approximately with the subject's internal soft tissue associated with the neck's anterior triangle. The device is capable of exerting negative pressure on the surface of a subject's neck, displacing the soft tissue forward and enlarging the airway.

The disclosed systems, structures, and methods are directed to an orbital angular momentum (OAM) receiver. The OAM receiver includes at least two receiver antenna elements to receive radiated OAM signal beams containing superposed order modes and to generate antenna element output signals based on the received OAM signal beams. The receiver antenna elements are positioned tangentially along a circular locus and spatially separated by a distance. A variable ratio combining unit operates to switch between the antenna output signals based on a high-rate periodic waveform that emulates unidirectional movement by the antenna elements to produce a pseudo-Doppler frequency shift. The variable ratio combining unit further modulates the antenna output signals based on the periodic waveform to impart a fractional pseudo-Doppler shift to each OAM mode and combines the modulated antenna element output signals in accordance with the fractional pseudo-Doppler shift to facilitate separation of the OAM modes.

A directional coupler includes: a first waffle-iron ridge waveguide extending from one end to other end; a second waffle-iron ridge waveguide extending from one end to the other end; a first bypass waveguide connecting a first site of the first waffle-iron ridge waveguide and a first site of the second waffle-iron ridge waveguide; and a second bypass waveguide connecting a second site of the first waffle-iron ridge waveguide and a second site of the second waffle-iron ridge waveguide.