A Doherty amplifier includes a peaking amplifier, a carrier amplifier, and a combining node electrically connected to the carrier amplifier and the peaking amplifier. The Doherty amplifier includes a harmonic control circuit coupled to the combining node. The harmonic control circuit includes an inductor and a capacitor and the inductor and capacitor are connected in series between the first current conducting terminal and a ground reference node. An inductance value of the inductor of the harmonic control circuit and a capacitance value of the capacitor of the harmonic control circuit are selected to terminate second order harmonic components of a fundamental frequency of a signal generated by the carrier amplifier.

An active balun circuit includes first and second transistors having emitters electrically coupled to each other and configured to output differential signals and a circuit element coupled between the connection point of the emitter of the first transistor and the emitter of the second transistor and a reference potential. The impedance of the circuit element at a particular frequency of the input signal appears significantly larger than impedances at other frequencies. An input signal from an input terminal is inputted to the base of the first transistor. The reference potential is applied to the base of the second transistor. A supply voltage is applied to the collector of the first transistor and the collector of the second transistor. A signal from the collector of the first transistor and a signal from the collector of the second transistor are outputted as the differential signals.

An amplitude and phase control device includes a signal dividing unit to divide a transmission signal into first and second signals and output the first and second signals to a Doherty amplifier, an error calculating unit to acquire, from the Doherty amplifier, a synthesized signal of first and second signals amplified by the Doherty amplifier, multiply the synthesized signal by a reciprocal of a gain of the Doherty amplifier, and calculate an error between a synthesized signal after being multiplied by the reciprocal and the transmission signal, and a controlling unit to control an amplitude of each of the first signal and the second signal output from the signal dividing unit depending on the error calculated by the error calculating unit, and control a phase difference between the first signal output from the signal dividing unit and the second signal output from the signal dividing unit depending on the error.

According to at least one example of the disclosure, a power amplifier is provided comprising a first power switch of a first type being configured to receive an input signal and provide an amplified output signal to an output connection configured to be coupled to a load, and a second power switch of a second type different than the first type, the second power switch being configured to improve a linearity of the power amplifier and being coupled to the output connection.

An apparatus for detecting difference in operating characteristics of a main circuit by using a replica circuit is presented. In one exemplary case, a sensed difference in operating characteristics of the two circuits is used to drive a tuning control loop to minimize the sensed difference. In another exemplary case, several replica circuits of the main circuit are used, where each is isolated from one or more operating variables that affect the operating characteristic of the main circuit. Each replica circuit can be used for sensing a different operating characteristic, or, two replica circuits can be combined to sense a same operating characteristic.

An embodiment of a dual-path amplifier includes a power splitter connected to first and second power amplifiers respectively connected to first and second transmission lines connected to a power combiner having a phase-offset deficit at the second harmonic frequency 2f0, where the first and second transmission lines are designed to provide a complementary phase offset at 2f0 substantially equal to the phase-offset deficit such that the two amplified signals will be combined at the power converter with a total phase offset at 2f0 of about 180 degrees in order to reduce harmonic distortion in the amplified output signal, without substantially diminishing the output power at the fundamental frequency f0. In certain PCB-based implementations, the transmission lines include metal traces and lumped elements providing different impedance transformations that achieve the complementary phase offset, where the metal traces may have significantly different physical and electrical characteristics.

An amplifier includes a package that includes a carrier amplifier having a carrier amplifier input and output, a peaking amplifier having a peaking amplifier input and output, and corresponding input and output leads. The package includes a first integrated passive device including a first capacitor structure. The first integrated passive device includes a first contact pad coupled to the peaking amplifier output and a second contact pad coupled to the peaking output lead. The package includes a second integrated passive device including a second capacitor structure. The second integrated passive device includes a third contact pad coupled to the carrier amplifier output and a fourth contact pad coupled to the carrier output lead. The amplifier includes input circuitry a combining node configured to combine a carrier output signal and a peaking output signal.

Provided are a matching network, an antenna circuit and an electronic device. The matching network includes a first inductor, a second inductor, and a third inductor, the first inductor having two ends serving as a pair of output terminals, the second inductor having two ends serving as a first pair of input terminals, and the third inductor having two ends serving as a second pair of input terminals, where a first coupling coefficient between the first inductor and the second inductor is greater than a second coupling coefficient between the first inductor and the third inductor. According to the matching network, the matching network can present a rather large resistance value conversion ratio even with a rather small area taken by inductors, the circuit design can be more flexible, and the signal interference can be lowered.

Provided is a method of processing an input signal of an amplifier in an electronic device, the method including obtaining a pre-distorter configured to pre-distort an input signal of the amplifier by using a pretrained neural network model to pre-distort the input signal of the amplifier based on signals input to and output from the amplifier, which are obtained while the amplifier operates in a plurality of different environments, and a plurality of pieces of environmental information corresponding to the plurality of different environments, obtaining an input signal for the amplifier, obtaining information about an environment of the amplifier, pre-distorting the input signal by using the pre-distorter based on the obtained environmental information to prevent an output signal in response to the input signal to be processed by the amplifier from being distorted, and inputting the pre-distorted input signal to the amplifier.

Apparatus and methods for load modulated power amplifiers are provided. In certain embodiments, a load modulated power amplifier system includes a power amplifier that receives a radio frequency signal at an input and provides an amplified radio frequency signal at an output, and a controllable load impedance coupled to the output of the power amplifier. The controllable load impedance receives an envelope signal that changes in relation to an envelope of the radio frequency signal, and the envelope signal is operable to control an impedance of the controllable load impedance to modulate a load at the output of the power amplifier.