A phase shifter for altering the phase of a radio frequency signal is disclosed herein. A Lange coupler is used having reflective ports that are coupled to artificial transmission lines. The artificial transmission lines provide a reflection transmission path, the length of which can be determined by digital control lines. Transistors placed along the length of the central trace provide independent paths to ground that serve to shorten the electrical length of the ATL. Accordingly, by selectively turning the transistors on/off, the electrical length of the ATL can be selected and thus the amount of phase delay introduced by the phase shifter.

A passive vector modulator (PVM) includes a divider that splits an input signal into a first divided signal and a second divided signal 90° apart in phase. The PVM includes a switched transformer phase shifter including primary windings to form first primary windings and second primary windings receiving the first divided signal and the second divided signal respectively. First secondary windings are coupled to the first primary windings, the first secondary windings being center-tapped and outputting first and second phase shifted output signals, phase shifted 180° and 0° respectively. Second secondary windings are coupled to the second primary windings, the second secondary windings being center-tapped and outputting third and fourth phase shifted signals, phase shifted 270° and 90° respectively. The PVM includes a switch configured to receive the phase shifted output signals. The switch selectively outputs one of the phase shifted output signals, or a combination, from the PVM.

The present disclosure is directed to a coil unit decoupling apparatus and a magnetic resonance system. The apparatus is connected to a first coil unit and a second coil unit in a magnetic resonance system, and is configured to separate, by using a distribution characteristic of a spatial quadrature field between the first coil unit and the second coil unit, a Helmholtz signal and an anti-Helmholtz signal from signals received from the first coil unit and the second coil unit, so as to implement decoupling between the first coil unit and the second coil unit. This facilitates the complexity of decoupling coil units being reduced.

The present disclosure is directed to a coil unit decoupling apparatus and a magnetic resonance system. The apparatus is connected to a first coil unit and a second coil unit in a magnetic resonance system, and is configured to separate, by using a distribution characteristic of a spatial quadrature field between the first coil unit and the second coil unit, a Helmholtz signal and an anti-Helmholtz signal from signals received from the first coil unit and the second coil unit, so as to implement decoupling between the first coil unit and the second coil unit. This facilitates the complexity of decoupling coil units being reduced.

A phase shift element includes an antenna, a first dielectric layer, a ground plane mounted to a first surface of the first dielectric layer, a reflecting circuit, and a single antenna-reflector line connected between the antenna and the reflecting circuit through the ground plane and the first dielectric layer. The antenna-reflector line is formed of a conducting material. The reflecting circuit is mounted to a second surface of the first dielectric layer. The first surface is opposite the second surface. The reflecting circuit is configured to reflect a signal received on the single antenna-reflector line from the antenna back to the antenna on the single antenna-reflector line. The reflecting circuit is further configured to be switchable between four different impedance levels that each provide a different phase shift when the signal is reflected by the reflecting circuit.

A phase shift element includes an antenna, a first dielectric layer, a ground plane mounted to a first surface of the first dielectric layer, a reflecting circuit, and a single antenna-reflector line connected between the antenna and the reflecting circuit through the ground plane and the first dielectric layer. The antenna-reflector line is formed of a conducting material. The reflecting circuit is mounted to a second surface of the first dielectric layer. The first surface is opposite the second surface. The reflecting circuit is configured to reflect a signal received on the single antenna-reflector line from the antenna back to the antenna on the single antenna-reflector line. The reflecting circuit is further configured to be switchable between four different impedance levels that each provide a different phase shift when the signal is reflected by the reflecting circuit.

Disclosed is a dual-band phase shifter in which series/parallel resonance circuits are applied to a polyphase filter to implement a phase shifter, which is a core block of a multi-channel RFIC for implementing a phased array antenna system. The dual-band phase shifter may be configured by converting a capacitor (C) of an LC circuit or a CL circuit in the RFIC into a series resonance circuit and converting an inductor (L) thereof into a parallel resonance circuit, so that a signal generator operating in one frequency band can operate in a dual-band.

Disclosed is a dual-band phase shifter in which series/parallel resonance circuits are applied to a polyphase filter to implement a phase shifter, which is a core block of a multi-channel RFIC for implementing a phased array antenna system. The dual-band phase shifter may be configured by converting a capacitor (C) of an LC circuit or a CL circuit in the RFIC into a series resonance circuit and converting an inductor (L) thereof into a parallel resonance circuit, so that a signal generator operating in one frequency band can operate in a dual-band.

Methods and apparatus for implementing a power efficient amplifier device through the use of a main (primary) and auxiliary (secondary) power amplifier are described. The primary and secondary amplifiers operate as current sources providing current to the load. Capacitance coupling is used to couple the primary and secondary amplifier outputs. In some embodiments the combination of primary and secondary amplifiers achieve high average efficiency over the operating range of the device in which the primary and secondary amplifiers are used in combination as an amplifier device. The amplifier device is well suited for implementation using CMOS technology, e.g., N-MOSFETs, and can be implemented in an integrated circuit space efficient manner that is well suited for supporting RF transmissions in the GHz frequency range, e.g., 30 GHz frequency range. The primary amplifier in some embodiments is a CLASS-AB or B amplifier and the secondary amplifier is a CLASS-C amplifier.

Methods and apparatus for implementing a power efficient amplifier device through the use of a main (primary) and auxiliary (secondary) power amplifier are described. The primary and secondary amplifiers operate as current sources providing current to the load. Capacitance coupling is used to couple the primary and secondary amplifier outputs. In some embodiments the combination of primary and secondary amplifiers achieve high average efficiency over the operating range of the device in which the primary and secondary amplifiers are used in combination as an amplifier device. The amplifier device is well suited for implementation using CMOS technology, e.g., N-MOSFETs, and can be implemented in an integrated circuit space efficient manner that is well suited for supporting RF transmissions in the GHz frequency range, e.g., 30 GHz frequency range. The primary amplifier in some embodiments is a CLASS-AB or B amplifier and the secondary amplifier is a CLASS-C amplifier.