It is disclosed an amplifier for driving a capacitive load, comprising an input terminal adapted to receive an input voltage signal, an output terminal adapted to drive the capacitive load, a linear amplification stage, switching amplification stage, a capacitor, a first switch and a measurement and control circuit. The measurement and control circuit is configured to: measure the value of the current generated at the output from the linear amplification stage and generate a driving voltage signal of the switching amplification stage; generate the first switching signal to open the first switch and generate an enabling signal to enable the operation of at least part of the switching amplification stage; generate the first switching signal to close the first switch and generate the enabling signal to disable the operation of the switching amplification stage; generate the first switching signal to open the first switch.

A Doherty amplifier includes a carrier amplifier, a peaking amplifier, and a phase compensation circuit. The carrier amplifier 11 includes a main amplifying element and a parasitic element, and the peaking amplifier includes an auxiliary amplifying element and a parasitic element. The phase compensation circuit has a negative electrical length that allows a total electrical length of a signal transmission path starting from an output source of the main amplifying element to a power combiner to become 180N90 where N is a positive integer. In addition, a signal transmission path starting from an output source of the auxiliary amplifying element to the power combiner has an electrical length of 180M180 where M is a positive integer.

A signal processing circuit reduces die size and power consumption for each antenna element. The signal processing circuit includes a first set of ports, a third port, a first path, a second path and a first transistor. The first path is between a first port of the first set of ports and the third port. The second path is between a second port of the first set of ports and the third port. The first transistor is coupled between the first path and the second path. The first transistor is configured to receive a control signal to control the first transistor to adjust an impedance between the first path and the second path.

A power amplifier module includes first and second amplifiers, a first bias circuit, and an adjusting circuit. The first amplifier amplifies a first signal. The second amplifier amplifies a second signal based on an output signal from the first amplifier. The first bias circuit supplies a bias current to the first amplifier via a current path on the basis of a bias drive signal. The adjusting circuit includes an adjusting transistor having first, second, and third terminals. A first voltage based on a power supply voltage is supplied to the first terminal. A second voltage based on the bias drive signal is supplied to the second terminal. The third terminal is connected to the current path. The adjusting circuit adjusts the bias current on the basis of the power supply voltage supplied to the first amplifier.

A multistage power amplifier includes a first amplification circuit disposed in a front stage of the multistage power amplifier, a first bias circuit configured to output a first bias current, a bias path circuit, an envelope detection circuit, and an alternating current (AC) path circuit. The envelope detection circuit is configured to output a direct current (DC) detection voltage based on an envelope signal of a radio frequency (RF) signal input to the first amplification circuit. The AC path circuit is configured to branch an AC signal from an input terminal of the first amplification circuit and transfer the AC signal to the first bias circuit, upon the first amplification circuit operating in a high power driving region based on the DC detection voltage. The first bias circuit is configured to compensate for the first bias current based on the AC signal transferred through the AC path circuit.

A signal processing method and system includes a baseband signal baseband signal processing module configured to perform slow envelope processing on a first signal, to obtain an envelope value E(n) of the first signal on which the slow envelope processing has been performed, obtain a phase value (n) based on E(n), where (n) and E(n) are in a linear relationship, and separate the first signal into a second signal and a third signal based on (n), where a phase difference between the second signal and the third signal is 2 (n), an amplifier configured to amplify the second signal and the third signal, and a synthesizer is configured to combine the amplified second signal and third signal to obtain a fourth signal.

A PA module includes: a multilayer substrate having a ground pattern layer connected to a ground of a power source; amplifier transistors disposed on the multilayer substrate; a bypass capacitor having one end connected to the collector of the amplifier transistor; a first wiring line connecting the emitter of the amplifier transistor and the ground pattern layer to each other; a second wiring line connecting the emitter of the amplifier transistor and the ground pattern layer to each other; a third wiring line connecting the other end of the bypass capacitor and the ground pattern layer to each other; and a fourth wiring line formed between the amplifier transistor and the ground pattern layer and between the bypass capacitor and the ground pattern layer and connecting the first wiring line and the third wiring line to each other.

Provided is a power amplification module that includes: a first transistor, a first signal being inputted to a base thereof; a second transistor, the first signal being inputted to a base thereof and a collector thereof being connected to a collector of the first transistor; a first resistor, a first bias current being supplied to one end thereof and another end thereof being connected to the base of the first transistor; a second resistor, one end thereof being connected to the one end of the first resistor and another end thereof being connected to the base of the second transistor; and a third resistor, a second bias current being supplied to one end thereof and another end thereof being connected to the base of the second transistor.

Various embodiments disclose a method and a device including: an antenna, a switching regulator, communication chip including an amplifier and a linear regulator operably connected to the amplifier and the switching regulator, the communication chip configured to transmit a radio-frequency signal from the electronic device through the antenna, and control circuitry configured to control the communication chip such that the linear regulator provides the amplifier with a voltage corresponding to an envelope of an input signal input to the amplifier, the input signal corresponding to the radio-frequency signal.

An amplifying apparatus is provided, which includes a power-source main line, a plurality of amplifying control devices which include an amplifier, a power-source branch line, an over current protector. The amplifier amplifies a high-frequency signal. The power-source branch line is branched from the power-source main line. The over current protector disposed for the power-source branch line is connected to the amplifier and configured to disconnect the power-source branch line based on drive current flowing through the amplifier from the power-source branch line. The power-source main line is common to the plurality of amplifying control devices.