Aspects of the disclosure relate to a radio frequency phase shifter. An example includes an amplification stage to produce an amplified voltage, the amplification stage having a first amplifier with a first input coupled to a first output of a hybrid coupler and a second amplifier with a complementary second input coupled to a complementary second output of the hybrid coupler. A vector modulation stage coupled to the amplification stage receives the amplified voltage and produces a modulated vector, the vector modulation stage has an in-phase section and a quadrature section to control the phase of the modulated vector in response to a phase control signal. A varactor coupled across the first input and the second input of the amplification stage adjusts the capacitance between the first input and the second input in response to a capacitance control signal.

An outphasing amplifier includes a first class-E power amplifier having an output coupled to a first conductor and an input receiving a first RF drive signal. A first reactive element is coupled between the first conductor and a second conductor. A second reactive element is coupled between the second conductor and a third conductor. A second class-E power amplifier includes an output coupled to a fourth conductor and an input coupled to a second RF drive signal, a third reactive element coupled between the second and fourth conductors. Outputs of the first and second power amplifiers are combined by the first, second and third reactive elements to produce an output current in a load. An efficiency enhancement circuit is coupled between the first and fourth conductors to improve power efficiency at back-off power levels. Power enhancement circuits are coupled to the first and fourth conductors, respectively.

An outphasing amplifier includes a first amplifier configured to amplify a first signal, a second amplifier configured to amplify a second signal of which a phase difference from the first signal changes, and a synthesizer that has a first transmission line through which a third signal output from the first amplifier passes, a second transmission line through which a fourth signal output from the second amplifier passes, a first coupling circuit that is separately provided from the first transmission line and is coupled to the first transmission line, a second coupling circuit that is separately provided from the second transmission line and coupled to the second transmission line, and a node that synthesizes the third signal having passed through the first transmission line and the fourth signal having passed through the second transmission line.

An apparatus is provided that includes circuitry for decomposing an input signal to multiple substantially constant-envelope components and an outphasing path for each substantially constant-envelope component. The apparatus also includes a modulator for discrete phase control in each outphasing path, an amplifier in each outphasing path and a combiner for combining output signals from the outphasing paths. A system and method are also provided.

A power supply modulation device includes a unit detecting, from a first digital signal, a first amplitude being the amplitude of a first analog signal provided to a first amplifier and detecting, from a second digital signal, a second amplitude being the amplitude of a second analog signal provided to a second amplifier; a unit that calculates a time differential value of a ratio of the first amplitude to a sum of the first amplitude and the second amplitude, and determines, on the basis of the time differential value, whether or not output impedance of a combining circuit that combines together the first analog signal amplified and the second analog signal changes along with a change in power of the combined signal; and a unit that controls a power supply voltage supplied to each of the first amplifier and the second amplifier, on the basis of the determination.

A tunable vector recombination amplifier comprises an input, an output, first and second amplifier circuit paths each including a respective phase shifter to receive a respective input signal from the input and to apply a respective phase shift to produce a respective phase-shifted signal, a respective interstage impedance matching network, and a respective amplifier connected between the respective phase shifter and interstage impedance matching network to receive and amplify the respective phase-shifted signal to produce a respective amplified signal, first and second controllable DC voltage sources each coupled to a respective amplifier and configured to provide a respective supply voltage to the respective amplifier, values of the supply voltages being independently controllable, and an output amplifier stage to receive, amplify, and vectorially combine the amplified signals to produce a combined signal having a specified phase determined by the phase shifts and supply-voltage values and a specified amplitude at the output.

The present disclosure generally relates to a high frequency amplifier, a system and a method for setting an operating state of a high frequency amplifier. The high frequency amplifier includes at least a first amplification circuit with a first frequency range, at least one second amplification circuit with a second frequency range, a hybrid coupler circuit with an isolated port, and a termination with at least one switch device. The hybrid coupler circuit is connected to output sides of the first amplification circuit and the second amplification circuit. The termination is connected with the isolated port. The high frequency amplifier has an operating range based on the first amplification circuit and the second amplification circuit. The high frequency amplifier has a load modulation in dependence of the first amplification circuit and the second amplification circuit. A first contact of the at least one switch device is directly coupled to ground.

An amplifier that is configured to amplify an RF signal includes a power combiner circuit. The power combiner circuit includes a first branch connected between a first RF input port and a summing node and a second branch connected between a second RF input port and the summing node. Each of the first and second branches includes an impedance inverter. The Chireix combiner is configured to present a Chireix load modulated impedance response to the first and second RF input ports. The power combiner circuit further includes compensation elements being configured to at least partially compensate for a reactance of the Chireix combiner circuit in a Doherty amplifier mode in which a signal is applied to the first RF input port and the second RF input port is electrically open.

An amplifier arrangement comprises N amplifier stages, wherein N is an integer equal or greater than four. The amplifier arrangement comprises a cascade of quarter wavelength transmission lines coupled between an output of an amplifier of a first amplifier stage and an output node of the amplifier arrangement, wherein the cascade comprises N−1 quarter wavelength transmission lines. An amplifier of the Nth stage is coupled to the output node, and remaining amplifiers between the first and Nth stages coupled to successive junctions in the cascade of quarter wavelength transmission lines. The amplifier arrangement is further configured such that the amplifier of the Nth stage is coupled to the output node via a connecting quarter wavelength transmission line, and whereby each of the remaining amplifiers of the N−2 stages closest to the output node is coupled by a respective connecting quarter wavelength transmission line to a respective junction of the cascade of quarter wavelength transmission lines.

A power amplifier includes an outphasing amplifier. The outphasing amplifier includes a first amplifier and a second amplifier, and is configured to provide a first amplified RF signal and a second amplified RF signal that is phase shifted from the first amplified RF signal. The power amplifier further includes an output circuit that is configured to combine RF power of the first and second amplified RF signals at a summing node. The output circuit includes a first branch connected between the first amplifier and a summing node and a second branch connected between the second amplifier and the summing node. The first and second branches are each configured to match an output impedance of the first and second amplifiers and to phase shift the first and second amplified RF signals for an outphasing operation using common reactive components for the match of the output impedance and the outphasing operation.