A balanced amplifier system having input and output quadrature couplers or equivalents thereof and two amplifiers there between. An RF signal is presented to a first input of an input quadrature coupler such that an amplified RF signal is output at a first output of the output quadrature coupler. A RF control signal is presented to a second input of the quadrature coupler such that an amplified control signal is outputted at the other output of the output quadrature coupler. The system is configured to reflect the amplified signal back into the second port of the output quadrature coupler in order to vary an impedance seen by the amplifiers of the balanced amplifier.

There is provided an amplifier device comprising a first directional coupler (12: 30, 32) and a second directional coupler (14: 30′, 32′) connected together so as to create separate upstream (16) and downstream (18) paths in which amplifier means (24, 24′) are located, wherein the first and second directional couplers (12, 14: 30, 32; 30′, 32′) are configured to have different signal loss characteristics, one of the directional couplers having low signal loss characteristics for upstream signals and the other directional coupler having low signal loss characteristics for downstream signals. The signal loss characteristics are preferably the coupling loss of each directional coupler (12, 14: 30, 32; 30′, 32′). The first and second directional couplers may each comprise a microstrip directional coupler (30; 30′) connected to a ferrite directional coupler (50; 50′).

An amplifier package includes a plurality of input leads, a plurality of transistor amplifiers having inputs respectively coupled to one of the plurality of input leads, and a quadrature hybrid coupler within the amplifier package and coupled between the plurality of input leads and the plurality of transistor amplifiers, wherein the quadrature hybrid coupler is configured to divide an input signal received from a first of the plurality of input leads between the plurality of transistor amplifiers.

An envelope tracking (ET) power amplifier apparatus is provided. The multi-mode power amplifier apparatus includes a pair of power amplifiers configured to amplify a radio frequency (RF) signal(s) and an output circuit that outputs the amplified RF signal(s) to a signal output(s). In examples disclosed herein, a control circuit can cause the multi-mode power amplifier apparatus to operate in different power management modes by changing a load impedance coupled to the signal output(s). In a non-limiting example, the control circuit can change a power management mode of the multi-mode power amplifier apparatus based on modulation bandwidth of the RF signal(s). As a result, the multi-mode power amplifier apparatus can operate across a wide range of modulation bandwidth without compromising efficiency and performance.

Systems and apparatuses are disclosed that include an RF generator configured to generate RF signals having a wavelength. Amplifiers are configured to receive and amplify the RF signals from the RF generator and are separated from each other by a separation distance in a range between about 0.2 times the wavelength and about 10.0 times the wavelength. A power management system is configured to control one or more of the amplifiers based on information received that is associated with the RF signals.

Circuits and methods for achieving good amplifier AM-AM and AM-PM metrics while achieving good power, PAE, linearity, and EVM performance. Embodiments compensate for a non-linear distortion profile (e.g., an AM-PM and/or AM-AM profile) in an amplifier by pre-processing an input signal, such as a radio-frequency signal, to alter the non-linear distortion profile of the input signal so as to compensate for the non-linear distortion profile imposed by a coupled device, such as an amplifier. An inventive aspect includes linearizing an output from an amplifier having a first non-linear distortion profile, including passing an input signal having a second non-linear distortion profile through a reflective hybrid coupler to a non-linear termination circuit, and reflecting a modified input signal from the non-linear termination circuit back through the reflective hybrid coupler as an output signal, the output signal having a third non-linear distortion profile shaped to compensate for the first non-linear distortion profile.

An average power tracking (APT) power amplifier apparatus is provided. In a non-limiting example, the APT power amplifier apparatus includes multiple sets of power amplifier circuits configured to amplify a radio frequency (RF) signal(s) for transmission in different polarizations (e.g., vertical and horizontal). In examples disclosed herein, the APT power amplifier apparatus can be configured to employ a single power management integrated circuit (PMIC) to provide an APT voltage to all of the power amplifier circuits for amplifying the RF signal(s). By employing a single PMIC in the APT power amplifier apparatus, it is possible to reduce footprint, power consumption, and costs of the APT power amplifier apparatus.

This application is generally related to methods and systems for improving amplifier performance. For example, the system includes two or more gain and phase modulators. The system also includes two or more component amplifiers operably coupled to, and downstream of, the power splitter, where each of the two or more component amplifiers is operably coupled to a respective one of the two or more gain and phase modulators. The system further includes a power combiner operably coupled to, and downstream of, the two or more component amplifiers, configured to output a power signal. The system even further includes a Walsh generator configured to generate and transmit first and second Walsh codes to each of the two or more gain and phase modulators. The first Walsh code is orthogonal to the second Walsh code. A first set of the first and second Walsh codes is inverted with respect to a second set of the first and second Walsh codes.

A radio frequency (RF) front end for wireless communications, in particular for use in a half duplex (HD) and/or full duplex (FD) transceiver. The RF front end is based on a quadrature balanced power amplifier (QBPA). The RF front end includes an antenna port for outputting a transmit signal to and receiving a receive signal from an antenna, and a receive port for outputting the receive signal to a signal processing section. Further, the QBPA is configured to receive a transmit input signal at a first port, receive a cancellation input signal at a fourth port, and receive the receive signal at a second port coupled to the antenna port.

A method for making a wideband Doherty amplifier with reduced plan width, adapted to transport a radio-frequency signal at a frequency value comprised within a frequency range defined between a minimum frequency value and a maximum frequency value, the amplifier including: a signal source adapted to generate an input signal; a hybrid coupler or a splitter network adapted to receive the input signal and divide it into first and second output signals phase-shifted by 90°; a carrier amplifier adapted to receive as input the first output signal; a peak amplifier adapted to receive as input the second output signal; an output network arranged between the carrier and peak amplifiers and a delivery node adapted to be connected to a load, the output network including a recombination node adapted to receive the signals output by the carrier amplifier and the peak amplifier, and a transmission line implemented as a printed circuit track applied to an insulating substrate, wherein capacitors are inserted on the track which are adapted to compensate for the non-ideality characteristics of the semiconductor used for making the line.