Embodiments of the disclosure generally relate to a multi-channel Doherty power amplifier, a multi-antenna transmitter, and a method for turning on the multi-channel Doherty amplifier. The multi-channel Doherty power amplifier includes: multiple input ports and the same number of output ports corresponding to multiple channels, the multiple channels having the same characteristics for radio signal amplification and transmission; multiple private peaking amplifiers corresponding to the multiple channels; and a common Doherty core shared by the multiple private peaking amplifiers. The multiple private peaking amplifiers and the common Doherty core are configured to amplify identical multi-channel signal for multiple inputs and multiple outputs, thus higher saving ratio and better channel performance (output power, linearity, efficiency, power gain etc.) consistency would be greatly improved.

A power amplifier having: a plurality of N amplifier modules, where N is an integer greater than one; an M:N power splitter having M inputs, where M is an integer less than N, and N outputs, each one of the N outputs being coupled to an input of a corresponding one of the plurality of N power amplifiers; a plurality of M delay lines, each one the M delay lines having an output coupled to a corresponding one of the M inputs of the M:N power splitter, each one of the plurality of M delay lines being coupled to a common input of the power amplifier.

A sequenced transmit muting wideband power amplifier is provided that includes at least one pre-driver stage having at least a first pre-driver and a second pre-driver. A mute switch selectively establishes a communication path between the first and second pre-drivers or couples the second pre-driver to a termination resistor. A pre-driver switch selectively activates/deactivates the first and second pre-drivers. A driver stage is in communication with the pre-driver stage and includes a first driver. A final amplifier stage is in communication with the driver stage and includes at least one second driver. At least one S-NBS switch is configured to selectively activate/deactivate the first driver and second driver. A controller is configured to activate the at least one pre-driver switch, the mute switch, the at least one S-NBS switch to selectively place the amplifier in one of a transmit mode and a mute mode.

A Radio Frequency (RF) circuit including a receive path, a transmit path, a switching circuit, and an output configured to receive RF signals from an antenna in a receive mode of operation, and to provide RF signals to the antenna in a transmit mode of operation. The receive path is configured to be coupled between a low-noise amplifier and the output. The switching circuit is located in the receive path and is configured, in the receive mode, to selectively couple the low-noise amplifier to the output and to pass the received RF signals from the output to the low-noise amplifier. The transmit path is configured to be coupled between a power amplifier and the output, to provide, in the transmit mode, signals from the power amplifier to the output, bypassing the switching circuit, and to have, in receive mode of operation, an off-state impedance of at least 200+j*13 Ohm.

An impedance converter includes an insulating layer; a first wire provided on a first surface of the insulating layer and extending in a first direction; a second wire provided on a second surface of the insulating layer and extending in the first direction and face the first wire, the second surface being located on a side opposite to the first surface; a third wire provided on the first surface and extending in a second direction orthogonal to the first direction; a fourth wire provided on the second surface and extending in the second direction and face the third wire; a fifth wire provided on the first surface and extending in the second direction; and a sixth wire provided on the second surface and extending in the second direction and face the fifth wire.

A power amplifier includes a 3-dB coupler which splits a first signal into a second signal and a third signal lagging behind the second signal by 90°, a carrier amplifier, a peak amplifier, and a hybrid coupler. The carrier amplifier amplifies the second signal and outputs a fourth signal when the first-signal power level is a first level or higher. The peak amplifier amplifies the third signal and outputs a fifth signal when the first-signal power level is a second level or higher, which is higher than the first level. The hybrid coupler includes a first transmission line receiving the fourth signal at its first terminal, and a second transmission line receiving the fifth signal at its first terminal and being open at its second terminal. The first transmission line outputs, from its second terminal, an amplified first signal obtained by combining the fourth and fifth signals.

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 sequenced transmit muting wideband power amplifier is provided that includes at least one pre-driver stage having at least a first pre-driver and a second pre-driver. A mute switch selectively establishes a communication path between the first and second pre-drivers or couples the second pre-driver to a termination resistor. A pre-driver switch selectively activates/deactivates the first and second pre-drivers. A driver stage is in communication with the pre-driver stage and includes a first driver. A final amplifier stage is in communication with the driver stage and includes at least one second driver. At least one S-NBS switch is configured to selectively activate/deactivate the first driver and second driver. A controller is configured to activate the at least one pre-driver switch, the mute switch, the at least one S-NBS switch to selectively place the amplifier in one of a transmit mode and a mute mode.

A Radio Frequency (RF) circuit including a receive path, a transmit path, a switching circuit, and an output configured to receive RF signals from an antenna in a receive mode of operation, and to provide RF signals to the antenna in a transmit mode of operation. The receive path is configured to be coupled between a low-noise amplifier and the output. The switching circuit is located in the receive path and is configured, in the receive mode, to selectively couple the low-noise amplifier to the output and to pass the received RF signals from the output to the low-noise amplifier. The transmit path is configured to be coupled between a power amplifier and the output, to provide, in the transmit mode, signals from the power amplifier to the output, bypassing the switching circuit, and to have, in receive mode of operation, an off-state impedance of at least 200+j*13 Ohm.