An integrated passive die includes a substrate, an input node, an output node, and RF filtering circuitry. The RF filtering circuitry includes a number of LC tank circuits coupled between the input node and the output node. Each one of the LC tank circuits include an inductor and a capacitor. The inductor is formed by a metal trace over the substrate. The capacitor is coupled in parallel with the inductor over the substrate. The inductor and the capacitor are provided such that a resonance frequency of the combination of the inductor and the capacitor is less than a self-resonance frequency of the inductor.

A method for reducing a quantity of cable runs to antennas can include the step of providing a circuit of reactive elements coupled between an input terminal and at least two output terminals. The circuit can be used to separate a broadband signal into two or more disjoint expected frequency ranges. The circuit can match the impedance at the at least two output terminals to the impedance expected by the antennas. The elements of the circuit can have reactances and arrangement so that when a broadband RF signal is applied at the input terminal, two or more disjoint expected frequencies can be applied to the respective output terminals. The power at each output terminal can sufficiently match the antennas' expected power, and insertion losses can be minimized.

Systems, devices, and methods for tunable filters that are configured to support multiple frequency bands, such as within the field of cellular radio communication, can include a first resonator and a second resonator configured to block signals within one or more frequency ranges, and one or more coupling element connected to both the first resonator and the second resonator. The one or more coupling element can be configured to provide low insertion loss within a pass band.

A diplexer includes dielectric layers stacked in a lamination direction. The diplexer includes a reference surface extending in a direction orthogonal or substantially orthogonal to the lamination direction, a common terminal on the reference surface, a high-pass circuit including a capacitor, a low-pass circuit including an inductor, a common line connecting the common terminal and a branch portion, a first via connecting the branch portion and the capacitor in the high-pass circuit, and a second via connecting the branch portion and the inductor in the low-pass circuit. The first via extends along the lamination direction from a first layer where the branch portion is located to a second layer where the capacitor in the high-pass circuit is located.

A hybrid microwave attenuator is constructed by forming a circuit and a housing. The circuit has two ports, a resistive component configured to attenuate some frequencies in an input signal (transmitted signal), and a dispersive component configured to attenuate some frequencies within a frequency range. The resistive component and the dispersive component are arranged in a series configuration relative to one another between the two ports of the circuit. The housing includes a closable structure in which the circuit is positioned, the structure being formed of a material that exhibits at least a threshold level of thermal conductivity, where the threshold level of thermal conductivity is achieved at a cryogenic temperature range in which a quantum computing circuit operates. The housing further includes a pair of microwave connectors, the pair of connectors being thermally coupled to the housing.

A filter includes a first resonant circuit having one or more first resonant frequencies, a second resonant circuit having one or more second resonant frequencies different from the first resonant frequency, and a switch connected to the first resonant circuit and the second resonant circuit. The switch switches between a first state in which a radio-frequency signal of the first resonant frequency flows from an IN terminal to an OUT terminal via the first resonant circuit and a radio-frequency signal of the second resonant frequency flows from the IN terminal to ground via the second resonant circuit and a second state in which a radio-frequency signal of the first resonant frequency flows from the IN terminal to ground via the first resonant circuit and a radio-frequency signal of the second resonant frequency flows from the IN terminal to the OUT terminal via the second resonant circuit.

A hybrid microwave attenuator is constructed by forming a circuit and a housing. The circuit has two ports, a resistive component configured to attenuate some frequencies in an input signal (transmitted signal), and a dispersive component configured to attenuate some frequencies within a frequency range. The resistive component and the dispersive component are arranged in a series configuration relative to one another between the two ports of the circuit. The housing includes a closable structure in which the circuit is positioned, the structure being formed of a material that exhibits at least a threshold level of thermal conductivity, where the threshold level of thermal conductivity is achieved at a cryogenic temperature range in which a quantum computing circuit operates. The housing further includes a pair of microwave connectors, the pair of connectors being thermally coupled to the housing.

A variable-frequency LC filter (1A) includes a multilayer circuit board, a series arm capacitor (11) formed in the multilayer circuit board and disposed in a series arm path that connects an input electrode to an output electrode, and a parallel arm inductor (21) formed in the multilayer circuit board and disposed in a parallel arm path that connects a ground electrode to a node (N1) in the series arm path. When the multilayer circuit board is viewed in plan, of the series arm capacitor (11) and the parallel arm inductor (21), only the parallel arm inductor (21) overlaps with the ground electrode.

A switch component includes a common terminal, at least two selection terminals, a switching circuit that selectively connects the common terminal to each of the at least two selection terminals, and an inductor. One end of the inductor is connected to one of the at least two selection terminals. The switching circuit is integrated with the inductor.

According to one embodiment, a compact broadband radio frequency (RF) receiver circuit includes a low noise amplifier which includes a first amplifier stage, a second amplifier stage, an inter-stage network including a higher order filter network, where the inter-stage network is coupled between the first amplifier stage and the second amplifier stage, and a double resonance transformer network coupled to an output of the second amplifier stage. The RF receiver circuit includes a low pass filter and a mixer circuit coupled between the low noise amplifier and the low pass filter.