A radiofrequency transmission line configured so as to allow a radiofrequency electrical signal to be transmitted between a first end and a second end, the transmission line including a main conductor and a ground plane electrically connected to an electrical ground of the transmission line. The ground plane includes a set of portions that are connected in series between the first end and the second end and a set of second capacitors, the set of portions including a set of second portions, each second capacitor being inserted between two contiguous second portions.

Fabrication of superconducting devices that combine or separate direct currents and microwave signals is provided. A method can comprise forming a direct current circuit that supports a direct current, a microwave circuit that supports a microwave signal, and a common circuit that supports the direct current and the microwave signal. The method can also comprise operatively coupling a first end of the direct current circuit and a first end of the microwave circuit to a first end of the common circuit. The direct current circuit can comprise a bandstop circuit and the microwave circuit can comprise a capacitor. Alternatively, the direct current circuit can comprise a bandstop circuit and the microwave circuit can comprise a bandpass circuit. Alternatively, the microwave circuit can comprise a capacitor and the direct current circuit can comprise one or more quarter-wavelength transmission lines.

A low frequency and direct current (DC) signal blocking device includes a dielectric substrate layer; a low frequency and DC signal blocking transmission line on a first surface of the substrate layer, where the low frequency and DC signal blocking transmission line has an input end and an output end; a metal layer on a second surface of the substrate layer, where there is at least one gap on the metal layer such that the metal layer is separated into at least a first sub-region and a second sub-region, where the gap is configured to block at least one of a low frequency signal and a DC signal; the substrate layer disposed between the low frequency and DC signal blocking transmission line and the metal layer; and a metal plate, wherein a dielectric layer is disposed between the metal plate and the metal layer.

A packaged RF power amplifier (RFPA) configured to increase video bandwidth is disclosed as well is a process for implementing a RF power device to increase video bandwidth. The RF power device including at least one transistor; an output matching circuit coupled to an output lead and to the at least one transistor; at least one bias feed circuit coupled to the at least one transistor; and at least one coaxial resonator coupled between the at least one transistor and the at least one bias feed circuit.

A filtering circuit includes at least two common-mode filters that are electrically coupled in series and magnetically coupled. The first common-mode filter includes first and second spiral inductors that are positively magnetically coupled and electrically isolated from each other. The second common-mode filter includes third and fourth spiral inductors that are positively magnetically coupled and electrically isolated from each other. The first and third spiral inductors are electrically connected in series and negatively magnetically coupled. Likewise, the second and fourth spiral inductors are electrically connected in series and negatively magnetically coupled.

A radio frequency power amplifier with harmonic control circuit as well as method for manufacturing the same are disclosed. According to an embodiment, a radio frequency power amplifier includes: a planar dielectric substrate, a first conductive layer and a second conducting layer. The first conductive layer is disposed on a first side of the planar dielectric substrate. The second conducting layer is disposed on a second side of the planar dielectric substrate. The first conductive layer has a pattern comprising one or more harmonic control circuits. The second conductive layer acts as a ground plane. The second side of the planar dielectric substrate is opposite to the first side of the planar dielectric substrate.

A converter (200) for converting a received radio frequency signal into a DC signal for powering a load (300). The converter (200) comprises a first rectifying arm (207) for generating a DC signal based on a first RF voltage input obtained from the received RF signal. A second rectifying arm (209) generates a DC signal based on a second RF voltage input obtained from the received RF signal. The received RF signal provides the voltage difference between the first RF voltage input and the second RF voltage input.

An isolator includes a conditioning circuit configured to filter signals communicated therethrough. The isolator also includes a coupling member comprising an anti-rotation feature. The anti-rotation feature is configured to prevent the conditioning circuit from rotating with respect to the coupling member to maintain a stable ground contact for the conditioning circuit. The isolator also includes a first annular circuit positioned around the coupling member. The isolator also includes a second annular circuit positioned around the coupling member and axially offset from the first annular circuit. The first and second annular circuits are configured to provide radio-frequency (RF) coupling with the coupling member.

An isolator includes a conditioning circuit configured to condition signals communicated therethrough. The isolator also includes a coupling member that includes an anti-rotation feature. The anti-rotation feature is configured to prevent the conditioning circuit from rotating with respect to the coupling member. The isolator also includes a coaxial circuit positioned around the coupling member. The coaxial circuit is configured to at partially attenuate direct current (DC) signals.

A radio-frequency signal grounding device for an antenna comprises: a substrate layer; a grounding transmission line on a first side of the substrate layer; a metal layer on a second side of the substrate layer, the metal layer including at least one gap such that the metal layer is divided into at least a first sub-region and a second sub-region, where the gap is configured to block at least one of a low frequency signal and a direct current signal; a metal plate; and a dielectric layer that is disposed between the metal plate and the metal layer. The radio-frequency signal grounding device can achieve good radio-frequency signal grounding and low frequency/direct current signal blocking within a limited space via a multi-coupling design.