Aspects of this disclosure relate to detecting power associated with an individual carrier of a carrier aggregated signal. In an embodiment, an aggregated carrier including at least a first carrier and a second carrier is provided. An indication of power of the first carrier of the aggregated carrier is detected. Separately from detecting the indication of power of the first carrier, an indication of power of the second carrier of the aggregated carrier is detected. The power associated with a radio frequency (RF) signal provided to an RF source associated with the first carrier can be adjusted based on the indication of power of the first carrier.

A multimode directional coupler is provided. In some embodiments, the multimode directional coupler is configured to receive a primary signal and a secondary signal at a first port of a primary waveguide. The primary signal is configured to propagate through the primary waveguide and be outputted at a second port of the primary waveguide. The multimode directional coupler also includes a secondary waveguide configured to couple the secondary signal from the primary waveguide with no coupling of the primary signal into the secondary waveguide. The secondary signal is configured to propagate through the secondary waveguide and be outputted from a port of the secondary waveguide.

Envelope trackers providing compensation for power amplifier output load variation are provided herein. In certain configurations, a radio frequency (RF) system includes a power amplifier that amplifies an RF signal, an output detector coupled to an output of the power amplifier and that generates an output detection signal, an input detector coupled to an input of the power amplifier and that generates an input detection signal, and an envelope tracker that generates a power amplifier supply voltage for the power amplifier based on an envelope of the RF signal. The envelope tracker compensates the power amplifier for output load variation based on the output detection signal and the input detection signal.

Circuits and methods for achieving high linearity, high efficiency power amplifiers, including digital predistortion (DPD) and pulse cancellation in switched-state RF power amplifier systems are described.

Circuits and methods for achieving high linearity, high efficiency power amplifiers, including digital predistortion (DPD) and pulse cancellation in switched-state RF power amplifier systems are described.

A transmission chain receives an incident signal to be transmitted having a first power and a first bandwidth. A first modulator frequency shifts a first signal derived from the incident signal to generate a first shifted signal at a modulation output. A power amplifier coupled to the modulation output amplifies an intermediate signal to generate an amplified output signal. A predistortion-signal-generating circuit generates, from the incident signal and from the amplified output signal in a second bandwidth that is larger than the first bandwidth, a predistortion signal having a second power lower than the first power. A second modulator frequency shifts a second signal derived from the predistortion signal to generate a second shifted signal for combination with the first shifted signal at said modulation output to produce the intermediate signal.

A power amplifier with adjustable voltage standing wave ratio is described which comprises an amplifier unit, a coupler configured to obtain an incident power and a coupled reflected power, and a power control unit. The power control unit is configured to control the amplifier unit. The power control unit has two power detectors configured to provide actuating variables which correspond to the incident power and the reflected power, respectively. The power control unit comprises two digital potentiometers which are configured to variably weight the actuating variables wherein the power control unit is configured to determine a control variable for the amplifier unit based on the actuating variables such that a predetermined power level related to a set value of the voltage standing wave ratio is not exceeded by the incident power and/or the reflected power. Further, a radio frequency electronic device and a method are described.

Apparatus and methods for power detection with enhanced dynamic range are provided. In certain embodiments, a front end system includes a power amplifier that amplifies a radio frequency (RF) input signal to generate an RF output signal, a directional coupler that generates a sensed RF signal based on sensing the RF output signal from the power amplifier, and a power detector that processes the sensed RF signal to generate a detection signal indicating an output power of the power amplifier. Additionally, the power detector includes two or more detection paths providing different amounts of gain to the sensed RF signal from the directional coupler.

Envelope trackers providing compensation for power amplifier output load variation are provided herein. In certain configurations, a radio frequency (RF) system includes a power amplifier that amplifies an RF signal, an output detector coupled to an output of the power amplifier and that generates an output detection signal, an input detector coupled to an input of the power amplifier and that generates an input detection signal, and an envelope tracker that generates a power amplifier supply voltage for the power amplifier based on an envelope of the RF signal. The envelope tracker compensates the power amplifier for output load variation based on the output detection signal and the input detection signal.

A digital microwave radio system includes a splitter that splits a common baseband input into two baseband outputs, first and second transmitters, each transmitter electrically connected to a baseband output of the splitter via a mixer, a common local oscillator electrically connected to the mixer of the first transmitter and the mixer of the second transmitter via an adjustable phase shifter, respectively, and a combiner. The common local oscillator is configured to up-convert each baseband output into a radio-frequency signal using a corresponding mixer. The combiner combines the two radio-frequency signals into a 0-degree phase-shift output and a 180-degree phase-shift output, respectively. A phase error control loop adjusts the phase shifter to minimize the 180-degree phase-shift radio-frequency output. A combiner gain control loop adjusts the output power level of the two transmitters in accordance with an actual power detector reading at the 0-degree phase-shift radio-frequency output.