A power amplifier arrangement for amplifying signals with multiple frequency bands. The power amplifier arrangement includes multiple inputs, multiple outputs, multiple main amplifiers, and multiple auxiliary amplifiers. Each of the multiple main amplifiers is configured as a narrow band amplifier for amplifying a signal within one frequency band of the multiple frequency bands, each auxiliary amplifier is configured as a wideband amplifier for amplifying signals within at least two frequency bands of the multiple frequency bands. The power amplifier arrangement further includes one or more input hybrid couplers and one or more output hybrid couplers.

A multiport amplifier MPA is provided with an N-input input network, INET, an N-output output network, ONET, and N amplifiers interposed between the INET and the ONET, the MPA comprising N wanted signal paths and N.(N1) null signal paths wherein N is divisible by 2, half of the N amplifier paths comprise a signal inversion with respect to the other half of the N amplifier paths, the INET and the ONET each comprise one or more quadrature hybrid couplers, QHC, wherein a pair of amplifier paths is arranged between the output of a first QHC in the INET and the input of a second QHC at the ONET, and each signal inversion is arranged in one of the amplifier paths of each pair of amplifier paths such that the ideal amplitude gain of at least one of the N.(Ni) null signal paths is zero.

A power amplifying converter comprises a multi-balanced-unbalanced converting unit, a plurality of power amplifying units, a plurality of dual-path power combining units and a differential power combining unit. The multi-balanced-unbalanced converting unit is provided with a first input/output end and a plurality of second input/output ends. Each of the power amplifying units is provided with a first input end electrically connected to the second input/output end, and a first output end. Each of the dual-path power combining units is provided with two second input ends electrically connected to the first output ends, and a second output end. The differential power combining unit is provided with two third input ends electrically connected to the second output ends, and a third output end. In this case, the multi-balanced-unbalanced converting unit is made up of a plurality of 1/12 wavelength transmission lines.

An amplifier architecture can include an input circuit for splitting a signal into first and second portions, and carrier and peaking amplification paths for receiving the first and second portions. The architecture can further include an output circuit having a balun transformer circuit with first and second coils, with the first coil between first and second ports, the second coil between third and fourth ports, the first and third ports coupled by a first capacitance, and the second and fourth ports coupled by a second capacitance. The first port can receive a first signal from the carrier amplification path, and the fourth port can receive a second signal from the peaking amplification path. The second port can provide a combination of the first signal and the second signal as an amplified signal. A termination circuit can be provided to couple the third port to a ground.

According to some aspects, a circuit is provided comprising a plurality of Josephson junctions arranged in series in a loop, at least one magnetic element producing magnetic flux through the loop, a plurality of superconducting resonators, each resonator coupled to the loop between a different neighboring pair of Josephson junctions of the plurality of Josephson junctions, a plurality of ports, each port coupled to at least one of the plurality of resonators at ends of the resonators opposite to ends at which the resonators are coupled to the loop, and at least one controller configured to provide input energy to each of the plurality of ports that causes the circuit to function as a circulator between the plurality of ports.

A multistage linear power amplifier receiving an input signal. The multistage linear power amplifier comprises a plurality of Class-AB amplifiers connected in a cascade configuration. The plurality of Class-AB amplifiers amplifies the input signal to generate an amplified input signal. At least one of the plurality of Class-AB amplifiers is biased such that the multistage linear power amplifier emulates a Class-C amplifier.

An RF amplifier utilizes first and second main amplifiers in a balanced amplifier configuration with first and second auxiliary amplifiers connected in parallel across the first and second main amplifiers, respectively. The main and the auxiliary amplifiers are biased such that the third-order nonlinearity components in the combined output current are reduced. A common or independent bias control circuit(s) control(s) the DC operating bias of the auxiliary amplifiers and establishes DC operating points on curves representing third-order nonlinear components within the drain current having a positive slope (opposite to the corresponding slope of the main amplifiers). This results in reduction of overall third-order nonlinear components in combined currents at the output. In another embodiment, a phase shift of an input to one auxiliary amplifier is used to provide a peak in minimization at a frequency associated with the phase shift.

In dividing units, signals propagating between input ports- and output ports and between input ports and output ports have phases shifted by 90 from phases of signals propagating between the input ports and the output port and between the input ports and the output ports. Amplifiers output amplified signals that are in phase to the dividing units. A combining and dividing unit outputs a combined signal obtained by combining signals from the output ports of the dividing units to an input port of a combining unit. A combining and dividing unit outputs a combined signal obtained by combining signals from the output ports of the dividing units to an input port of a combining unit.

Described herein is a reconfigurable asymmetrical load-modulated balanced amplifier. The reconfigurable asymmetrical load-modulated balanced amplifier can include a radio frequency (RF) input port, an RF output port, a peaking amplifier circuit operably coupled between the RF input and RF output ports, where the peaking amplifier circuit is a balanced amplifier that comprises a pair of asymmetrical power amplifiers, and a carrier amplifier circuit operably coupled to the RF input port.

A multiport amplifier MPA is provided with an N-input input network, INET, an N-output output network, ONET, and N amplifiers interposed between the INET and the ONET, the MPA comprising N wanted signal paths and N.Math.(N1) null signal paths wherein N is divisible by 2, half of the N amplifier paths comprise a signal inversion with respect to the other half of the N amplifier paths, the INET and the ONET each comprise one or more quadrature hybrid couplers, QHC, wherein a pair of amplifier paths is arranged between the output of a first QHC in the INET and the input of a second QHC at the ONET, and each signal inversion is arranged in one of the amplifier paths of each pair of amplifier paths such that the ideal amplitude gain of at least one of the N.Math.(Ni) null signal paths is zero.