The present disclosure provides a radio frequency duplexer circuit and a radio frequency substrate. The radio frequency duplexer circuit includes a first terminal, a second terminal, a third terminal, a low-pass filter, and a high-pass filter. The low-pass filter includes N first filter sub-circuits coupled in series and a first tuning sub-circuit. Among the N first filter sub-circuits coupled in series, a first end of a 1.sup.st first filter sub-circuit is coupled to the first terminal, and a second end of a N.sup.th first filter sub-circuit is coupled to the second terminal. The high-pass filter includes M second filter sub-circuits coupled in series and a second tuning sub-circuit. Among the M second filter sub-circuits coupled in series, a first end of a 1.sup.st second filter sub-circuit is coupled to the first terminal, and a second end of a M.sup.th second filter sub-circuit is coupled to the third terminal.

A circuit device includes a semiconductor device and an impedance matching network. The impedance matching network includes a superconductor material forming at least one inductor of the circuit device, and the superconductor material exhibits a kinetic inductance per unit square when in a superconducting state. The impedance matching network is configured to transform an impedance of the semiconductor device to match a predetermined second impedance during operation of the circuit device.

A high-order filter with a capacitive inner tapping technique is disclosed. The filter includes an inductor and a first resonant circuit including a first portion of the inductor and a first capacitor. The first resonant circuit is configured to attenuate first frequency components of an input signal above a cutoff frequency to generate a filtered signal. The filter further includes a second resonant circuit coupled in parallel with the first resonant circuit and including the first portion of the inductor and a second capacitor. The second resonant circuit is configured to attenuate the first frequency components of the input signal to generate the filtered signal. A third resonant circuit includes a second portion of the inductor and a third capacitor, wherein the third resonant circuit is configured to attenuate second frequency components of the filtered signal above the cutoff frequency to generate an output signal.

A high-order filter with a capacitive inner tapping technique is disclosed. The filter includes an inductor and a first resonant circuit including a first portion of the inductor and a first capacitor. The first resonant circuit is configured to attenuate first frequency components of an input signal above a cutoff frequency to generate a filtered signal. The filter further includes a second resonant circuit coupled in parallel with the first resonant circuit and including the first portion of the inductor and a second capacitor. The second resonant circuit is configured to attenuate the first frequency components of the input signal to generate the filtered signal. A third resonant circuit includes a second portion of the inductor and a third capacitor, wherein the third resonant circuit is configured to attenuate second frequency components of the filtered signal above the cutoff frequency to generate an output signal.

A system of at least two units that transmit and/or receive a signal at a first or a second frequency, respectively, each of the units being individually connected to the antenna, which is common to a first branch and to a second branch, respectively. The first branch or the antenna includes first passive electronics preventing passage of the signal at the second frequency to the first unit and allowing passage of the signal at the first frequency to the antenna. The second branch or the antenna includes second passive electronics preventing passage of the signal at the first frequency to the second unit and allowing passage of the signal at the second frequency to the antenna.

A matching circuit, a radio frequency front-end power amplification circuit, and a mobile communication device are provided. The matching circuit is configurable for the radio frequency front-end power amplification circuit, including a first impedance matcher, a first bandpass filter, a first wave trap, and a first matching unit. An impedance of the first impedance matcher is a first preset impedance at a first frequency, the first bandpass filter is bridged between a front end of the first impedance matcher and ground, the first bandpass filter enables a signal of the first frequency to pass through, and suppresses at least one of a signal of a second frequency and a signal of third harmonic generation of the first frequency. The second frequency is lower than the first frequency. The first wave trap is bridged between a rear end of the first impedance matcher and the ground.

Disclosed are example embodiments of a circuit comprising a first inductor-capacitor (LC) loop, a second LC loop having at least one of a series connection or parallel connection to the first LC loop, and a gyrator coupled between the first LC loop and the second LC loop. In an example, the first LC and the second LC loop each include an inductive element (L) and a capacitive (C) element coupled to each other in series. In another example, the first LC and the second LC loop each include an inductive element (L) and a capacitive (C) element coupled to each other in parallel.

A band pass filter includes: a resonator including a first inductor and a first capacitor coupled in series between a first port and a second port; a second capacitor coupled in parallel to the resonator; and a third capacitor connected between one end of the second capacitor and the ground to perform a low pass filter function.

An on-chip microwave filter circuit includes a substrate formed of a first material that exhibits at least a threshold level of thermal conductivity, wherein the threshold level of thermal conductivity is achieved at a cryogenic temperature range in which a quantum computing circuit operates. The filter circuit further includes a dispersive component configured to filter a plurality of frequencies in an input signal, the dispersive component including a first transmission line disposed on the substrate, the first transmission line being formed of a second material that exhibits at least a second threshold level of thermal conductivity, where the second threshold level of thermal conductivity is achieved at a cryogenic temperature range in which a quantum computing circuit operates. The dispersive component further includes a second transmission line disposed on the substrate, the second transmission line being formed of the second material.

A multilayer circuit board with an LC resonant circuit that has an electronic component package including the multilayer circuit board with the LC resonant circuit are provided. The multilayer circuit board with the LC resonant circuit configured by alternately laminating conductive layers and insulating resin layers on both sides of a core substrate includes a first set of wiring lines, a set of vias, and a second set of wiring lines. The first set of wiring lines configures both ends of the LC resonant circuit and is formed in a first one of the conductive layers. The set of vias extends through the insulating resin layers. The second set of wiring lines is connected to an input/output terminal of the LC resonant circuit and is formed in a second one of the conductive layers. The first set of wiring lines is connected to the second set of wiring lines.