Abstract: This invention relates to a power amplifier device comprising an amplifier component (A) operable to receive an input signal (s;) and to provide an amplified output signal (so), according to a control signal (ctrl), an envelope tracking modulator (ET), providing the control signal (ctrl) according to a static voltage (V s) and a dynamic voltage (V D), a power supply (S) providing said static and dynamic voltages according to measurements performed by a power sensor (PS) on the amplified output signal, so that the static voltage (Vs) is determined as a mean value of the output signal (So) over a predetermined time duration.

Abstract: A variable capacitance cell includes a hybrid coupler including a first port, a second port, a third port, and a fourth port. A first variable capacitance is connected to the second port. The first variable capacitance includes one or more first variable micro-electromechanical system (MEMS) capacitor. A second variable capacitance is connected to the third port. The second variable capacitance includes one or more second variable MEMS capacitors. Control signals are applied to the first and second variable capacitances to selectively change the capacitances of the first and second variable capacitances, thereby modifying a phase difference between a signal input at the first port and a signal output from the fourth port.

Abstract: A variable capacitance cell includes a hybrid coupler including a first port, a second port, a third port, and a fourth port. A first variable capacitance is connected to the second port. The first variable capacitance includes one or more first variable micro-electromechanical system (MEMS) capacitor. A second variable capacitance is connected to the third port. The second variable capacitance includes one or more second variable MEMS capacitors. Control signals are applied to the first and second variable capacitances to selectively change the capacitances of the first and second variable capacitances, thereby modifying a phase difference between a signal input at the first port and a signal output from the fourth port.

Abstract: This invention relates to a power amplifier device comprising an amplifier component (A) operable to receive an input signal (s;) and to provide an amplified output signal (so), according to a control signal (ctrl), an envelope tracking modulator (ET), providing the control signal (ctrl) according to a static voltage (V s) and a dynamic voltage (V D), a power supply (S) providing said static and dynamic voltages according to measurements performed by a power sensor (PS) on the amplified output signal, so that the static voltage (Vs) is determined as a mean value of the output signal (So) over a predetermined time duration.