A high frequency amplifier 1 includes an input terminal P.sub.IN, an output terminal P.sub.OUT, a transistor 5 configured to amplify an RF signal applied to the input terminal P.sub.IN, a matching circuit 9 for a fundamental of the RF signal and a reflection circuit 7 for a harmonic relative to the fundamental, the matching circuit 9 and the reflection circuit 7 being connected in series between the transistor 5 and the output terminal P.sub.OUT, an extraction circuit 13 configured to extract a harmonic appearing at the output terminal P.sub.OUT, processing circuits 15, 17 configured to adjust a phase and intensity of the harmonic extracted by the extraction circuit 13, and a multiplexing circuit 19 configured to multiplex the harmonic processed by the processing circuits 15, 17 to the harmonic reflected by the reflection circuit 7 and give the multiplexed harmonic to the transistor 5.

Embodiments of a method and a device are disclosed. In an embodiment, a Doherty amplifier module includes a substrate including a mounting surface, and further includes a first amplifier die, a second amplifier die, and a third amplifier die on the mounting surface. The first amplifier die is configured to amplify a first radio frequency (RF) signal along a first signal path, the second amplifier die is configured to amplify a second RF signal along a second signal path, and the third amplifier die is configured to amplify a third RF signal along a third signal path. A side of the first amplifier die including a first output terminal faces a side of the second amplifier die including a second output terminal. The second signal path is parallel to the first signal path, and the third signal path is orthogonal to the first and second signal paths.

An amplifier includes a driver stage amplifier transistor and a final stage amplifier transistor, which are integrated in a semiconductor die. The driver stage amplifier transistor has a driver stage input, a driver stage output, and an output impedance, and the driver stage amplifier transistor is configured to operate using a first bias voltage at the driver stage output. The final stage amplifier transistor has a final stage input, a final stage output, and an input impedance. The final stage input is electrically coupled to the driver stage output. The final stage amplifier transistor is configured to operate using a second bias voltage at the final stage output, and the second bias voltage is at least twice as large as the first bias voltage.

An amplifier includes a driver stage amplifier transistor and a final stage amplifier transistor, which are integrated in a semiconductor die. The driver stage amplifier transistor has a driver stage input, a driver stage output, and an output impedance, and the driver stage amplifier transistor is configured to operate using a first bias voltage at the driver stage output. The final stage amplifier transistor has a final stage input, a final stage output, and an input impedance. The final stage input is electrically coupled to the driver stage output. The final stage amplifier transistor is configured to operate using a second bias voltage at the final stage output, and the second bias voltage is at least twice as large as the first bias voltage.

A multiple-stage amplifier includes a driver stage transistor characterized by a first power density, and a final stage transistor characterized by a second power density that is larger than the first power density. A first drain bias circuit is coupled to a first drain terminal of the driver stage transistor, and is configured to provide a first drain bias voltage to the first drain terminal. A second drain bias circuit is coupled to a second drain terminal of the final stage transistor, and is configured to provide a second drain bias voltage to the second drain terminal, where the second drain bias voltage equals the first drain bias voltage. An interstage impedance matching circuit is coupled between the first drain terminal and a gate terminal of the final stage transistor. The multiple-stage amplifier may be included in a Doherty power amplifier, a transceiver, and/or a transceiver array.

A load-insensitive power amplifier power detector that excludes the use of couplers is disclosed. The load-insensitive power amplifier power detector may include a voltage sampling circuit in electrical communication with a collector of a power amplifier and configured to sample a first voltage from the power amplifier. The load-insensitive power amplifier power detector may include a current sampling circuit in electrical communication with the collector of the power amplifier and configured to sample an output current from the power amplifier. Further, the load-insensitive power amplifier power detector may include a current-to-voltage converter connected between the voltage sampling circuit and an output of the load-insensitive power amplifier power detector. The current-to-voltage converter may be configured to convert the output current to obtain a second voltage. Moreover, a combination of the first voltage and the second voltage may form a detector voltage corresponding to an incident power of the power amplifier.

A power amplifying module includes a first input terminal, a second input terminal, a first power amplifier, a stage matching circuit, a bypass line, and a second power amplifier. The first input terminal receives a first input signal in a first operation mode. The second input terminal receives a second input signal in a second operation mode which is different from the first operation mode. The first power amplifier amplifies the first input signal and outputs a first amplified signal. The stage matching circuit is disposed downstream of the first power amplifier and receives the first amplified signal. The bypass line outputs the second input signal to the inside of the stage matching circuit not through the first power amplifier. The second power amplifier is disposed downstream of the stage matching circuit, and amplifies the first amplified signal or the second input signal and outputs a second amplified signal.

Provided is an amplification circuit that includes: a low-noise amplifier that includes an FET as an amplification element and that amplifies a radio-frequency signal inputted to the gate of the FET; an input matching network that matches the input impedance of the low-noise amplifier; and a switch that is serially connected between ground and a node on a line connecting the input matching network and the gate of the FET to each other.

Disclosed is power amplifier circuitry having a bipolar junction power transistor with a base, a collector, and an emitter. The power amplifier circuitry includes bias correction sub-circuitry configured to generate a compensation current substantially opposite in phase and substantially equal in magnitude to an error current passed by a parasitic base-collector capacitance inherently coupled between the base and collector, wherein the bias correction sub-circuitry has a compensation output coupled to the base and through which the compensation current flows to substantially cancel the error current.

A wireless access point is configured to regularly monitor the status of WLAN, WAN and ePDG data links to determine whether the current connections are sufficient to support VoWiFI services. When a device connects to the WLAN of the hub and attempts to switch from its VoLTE service to VoWiFi via the hub, the hub is configured to determine whether the current conditions can satisfy a VoWiFi connection. If the VoWiFi service can support the connection, the request is routed to the ePDG associated with the mobile device's subscriber LTE network. However, if the current conditions cannot satisfactorily support a VoWiFi connection such that incoming calls may be missed or the quality of active calls would not be clear, then the hub is configured to block the request so that the client device will time out and remain connected to VoLTE.