The integrated circuit includes a power amplifier intended to provide a signal in a fundamental frequency band, an antenna, and a matching and filtering network having a first section, a second section, and a third section. The three sections include LC arrangements configured to have an impedance matched to the power amplifier's output in the fundamental frequency band. The LC arrangements of the first section and the second section are configured to have resonant frequencies adapted to attenuate the harmonic frequency bands of the fundamental frequency band.

This application discloses a wireless communication apparatus and a signal processing method. The wireless communication apparatus includes a power amplifier and a bias circuit. The power amplifier includes a signal input port, a signal output port, a power supply port, and a bias port. The power amplifier is configured to: receive a power supply signal through the power supply port, receive a bias signal through the bias port, receive a radio frequency signal through the signal input port, and output a power amplified radio frequency signal. The bias circuit is configured to generate the bias signal. A timing feature of the bias signal is synchronized with a timing feature of a switch signal of a power amplifier, to compensate for a nonlinear change in the TDD scenario.

This application discloses example multi-phase-based Doherty power amplifier control methods and apparatus An example method includes obtaining a baseband signal and generating two vector signals based on the baseband signal, where the two vector signals each include a phase signal and amplitude signal, and the two vector signals are non-orthogonal signals. Amplitude control signals of a target power amplifier are obtained based on quantization encoding of amplitude signals of the two vector signals, where the target power amplifier includes a main and power amplifier, and the main and auxiliary power amplifier each include a plurality of working cells. Phase control signals of the target power amplifier are obtained based on phase signals of the two vector signals. Based on the phase control signals and the amplitude control signals, a plurality of working cells in the main power amplifier and the auxiliary power amplifier to output power signals are controlled.

A tracker module is provided that includes an external connection terminal, a tracker, and a variable low pass filter. The external connection terminal is connected to a power amplifier. The tracker supplies a power supply voltage to the power amplifier via the external connection terminal by using an envelope tracking method. The variable low pass filter is disposed on a path between the tracker and the external connection terminal. In the variable low pass filter, a first block includes at least one electronic component. A second block is a block that varies a cutoff frequency of the variable low pass filter. The second block is integrated with the tracker into one package. The first block is disposed separately from the tracker.

A radio frequency module is provided that includes a plurality of power amplifiers, an external connection terminal, a filter, and a switch. The amplifiers include a first power amplifier and a second power amplifier. The external connection terminal is connected to a tracker component configured to supply a power supply voltage to the power amplifiers. Moreover, the filter is not disposed on a first path between the external connection terminal and the first power amplifier, but instead it is disposed on a second path between the external connection terminal and the second power amplifier. The switch is configured to switch connection to the external connection terminal between the first path and the second path.

A radio-frequency circuit includes an amplifier circuit, a bias circuit, a bias control circuit, a comparing section, a signal input terminal, an antenna terminal, an attenuation circuit, and a control unit. The amplifier circuit includes a specific transistor. The bias circuit supplies a bias current or a bias voltage to the input terminal of the specific transistor. The bias control circuit supplies a control current or a control voltage to the bias circuit. The comparing section compares a threshold voltage with a power supply voltage of a power supply terminal connected to the output terminal of the specific transistor. The attenuation circuit is connected in a signal path between the signal input terminal and the antenna terminal and is capable of attenuating the radio-frequency signal. The control unit changes an attenuation of the attenuation circuit in accordance with a compared result of the comparing section.

A radio-frequency circuit includes an amplifier circuit, a bias circuit, a bias control circuit, a comparing section, a variable resistance circuit, and a control unit. The amplifier circuit includes a transistor that amplifies a radio-frequency signal input to an input terminal and outputs the radio-frequency signal from an output terminal. The bias circuit supplies a bias current or a bias voltage to the input terminal of the transistor. The comparing section compares a threshold voltage with a power supply voltage of a power supply terminal connected to the output terminal of the transistor. The variable resistance circuit is connected between the power supply terminal and the output terminal. The variable resistance circuit includes a parallel circuit made up of a resistive element and a switch element. The control unit changes a resistance value of the variable resistance circuit in accordance with a compared result of the comparing section.

Systems and methods for amplifying a signal is described. A circuit may convert an input radio frequency (RF) signal into a first RF signal with power level matching a power capacity of a first transistor of a first size in a carrier amplifier stage, a second RF signal with power level matching a power capacity of a second transistor of the first size in a peaking amplifier stage, and a third RF signal with third power level matching a power capacity of a third transistor of a second size in another peaking amplifier stage. The circuit may amplify the first, second, and third RF signals to generate first, second, and third amplified RF signals, respectively. The circuit may combine the first, second, and third amplified RF signals, into an output RF signal that is an amplified version of the input RF signal.

A method comprises obtaining a transmission signal to be power-amplified in a power amplifier (361) prior to transmission; separating the transmission signal into two or more polyphase components of the transmission signal; feeding one or more polyphase components of the transmission signal comprised in the two or more polyphase components to each of two or more parallel predistortion circuits (320,321,322); selecting a dedicated predistortion model and dedicated predistortion coefficients for each of the two or more parallel predistortion circuits (320,321,322); performing non-linear memory-based modeling on the transmission signal according to the selected dedicated predistortion models and coefficients using the one or more polyphase components; and combining output signals of the two or more parallel predistortion circuits (320,321,322) to form a predistorted transmission signal (y[n]) to be applied to the power amplifier (361).

A power amplifier structure includes at least one power amplifier circuit. The power amplifier circuit includes a transistor of a first type connected in series with a transistor of a second type connected between the same voltage supply. In a non-limiting nonexclusive example, an n-type transistor is connected in series with a p-type transistor connected between Vdd. The power amplifier structure can include two amplifier circuits configured in a differential amplifier structure. The differential amplifier structure includes two amplifier circuits operably connected in parallel between the same voltage supply.