The present disclosure in some embodiments relates to a method of calibrating a power amplifier performance and an apparatus therefor, which provide an optimal calibration of the output characteristics of a power amplifier to all possible combinations in the input signal source by enabling individualized calibrations for changes in the output characteristics at room temperature and changing temperatures, thereby improving the performance of the power amplifier.

A radio frequency (RF) power amplifier circuit with a diode linearizer circuit. The power amplifier circuit has an input and an output, as well as a power amplifier transistor with a first terminal connected to the input, a second terminal connected to the output, and a third terminal. The linearizer circuit is connected to the third terminal and to ground, and has a non-linear current-voltage curve as well as a non-linear capacitance. The linearizer circuit reduces inter-modulation products in a current through the power amplifier transistor from the second terminal to the third terminal that corresponds to an input signal applied to the input.

Disclosed are a radio frequency power amplifier for inhibiting a harmonic wave and stray, a chip and a communication terminal. The radio frequency power amplifier comprises a power source, an LDO circuit, a harmonic inhibition unit, a stray inhibition unit, an amplifying unit, and a low-pass matching network. On the one hand, by means of the power source being connected to the harmonic inhibition unit, harmonic waves and stray of the power source at a resonant frequency are inhibited. Additionally, by means of the stray inhibition unit reducing the gain of the amplifying unit at a resonant frequency, output of stray is reduced. On the other hand, by means of the low-pass matching network being embedded at an output end of the radio frequency power amplifier, harmonic waves and the stray of a radio frequency signal amplified by the amplifying unit at different frequencies is effectively inhibited.

A transistor circuit includes a transistor having a gate terminal and first and second conduction terminals, a first circuit configured to convert an AC input signal of the transistor circuit to a gate bias voltage and to apply the gate bias voltage to the gate terminal of the transistor, a second circuit configured to convert the AC input signal of the transistor circuit to a control voltage, and a switching circuit configured to apply a first voltage to the first conduction terminal of the transistor in response to the control voltage.

Disclosed examples include differential amplifier circuits and variable neutralization circuits for providing an adjustable neutralization impedance between an amplifier input node and an amplifier output node, including neutralization impedance T circuits with first and second impedance elements in series between the amplifier input and output, and a third impedance element, including a first terminal connected to a node between the first and second impedance elements, and a second terminal connected to a transistor. The transistor operates according to a control signal to control the neutralization impedance between the amplifier input node and the amplifier output node.

A transistor circuit includes a transistor having a gate terminal and first and second conduction terminals, a first circuit configured to convert an AC input signal of the transistor circuit to a gate bias voltage and to apply the gate bias voltage to the gate terminal of the transistor, a second circuit configured to convert the AC input signal of the transistor circuit to a control voltage, and a switching circuit configured to apply a first voltage to the first conduction terminal of the transistor in response to the control voltage.

A linearization circuit reduces intermodulation distortion in an amplifier that includes a first stage and a second stage. The linearization circuit receives a first signal that includes a first frequency and a second frequency and generates a difference signal having a frequency approximately equal to the difference of the first frequency and the second frequency, generates an envelope signal based at least in part on a power level of the first signal, and adjusts a magnitude of the difference signal based on the envelope signal. When the amplifier receives the first signal at an input terminal, the first stage receives the adjusted signal, and the second stage does not receive the adjusted signal, intermodulation between the adjusted signal and the first signal cancels at least a portion of the intermodulation between the first frequency and the second frequency from the output of the amplifier.

A linearization circuit that reduces intermodulation distortion in an amplifier output receives a first signal that includes a first frequency and a second frequency and generates a difference signal having a frequency approximately equal to the difference of the first frequency and the second frequency. The linearization circuit generates an envelope signal based at least in part on a power level of the first signal and adjusts a magnitude of the difference signal based on the envelope signal. When the amplifier receives the first signal at an input terminal and the adjusted signal at a second terminal, intermodulation between the adjusted signal and the first signal cancels at least a portion of the intermodulation products that result from the intermodulation of the first frequency and the second frequency.

Envelope-tracking control techniques are disclosed for highly-efficient radio frequency (RF) power amplifiers. In some cases, a III-V semiconductor material (e.g., GaN or other group III material-nitride (III-N) compounds) MOSFET including a high-k gate dielectric may be used to achieve such highly-efficient RF power amplifiers. The use of a high-k gate dielectric can help to ensure low gate leakage and provide high input impedance for RF power amplifiers. Such high input impedance enables the use of envelope-tracking control techniques that include gate voltage (Vg) modulation of the III-V MOSFET used for the RF power amplifier. In such cases, being able to modulate Vg of the RF power amplifier using, for example, a voltage regulator, can result in double-digit percentage gains in power-added efficiency (PAE). In some instances, the techniques may simultaneously utilize envelope-tracking control techniques that include drain voltage (Vd) modulation of the III-V MOSFET used for the RF power amplifier.

A radio frequency (RF) power amplifier circuit with a diode linearizer circuit. The power amplifier circuit has an input and an output, as well as a power amplifier transistor with a first terminal connected to the input, a second terminal connected to the output, and a third terminal. The linearizer circuit is connected to the third terminal and to ground, and has a non-linear current-voltage curve as well as a non-linear capacitance. The linearizer circuit reduces inter-modulation products in a current through the power amplifier transistor from the second terminal to the third terminal that corresponds to an input signal applied to the input.