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.

System and method for efficient operation of power amplifiers in dynamic carrier systems. In one example, the method includes determining a composite RMS power and peak power for a carrier configuration of an RF transmitter, determining a number of active banks of power amplifiers as a function of composite RMS power and peak power, and determining a number of active power amplifiers within a bank of power amplifiers as a function of composite RMS power and peak power. The method also includes activating a first bank of power amplifiers and/or a second bank of power amplifiers based on the determined number of active banks of power amplifiers and activating a subset of a one or more first power amplifiers of the first bank of power amplifiers and a one or more second power amplifiers of the second bank of power amplifiers based on the determined number of active power amplifiers.

An envelope tracking (ET) power amplifier apparatus is provided. The ET power amplifier apparatus includes a pair of power amplifiers configured to amplify a pair of radio frequency (RF) signals based on a pair of ET voltages. In one aspect, each of the RF signals is split before amplification and recombined after amplification. As such, the power amplifiers can operate based on half the peak power of the RF signals to help improve operating efficiency of the power amplifiers. In another aspect, the RF signals are pre-processed prior to amplification to form a pair of composite RF signals with similar average power such that the power amplifiers can operate based on substantially similar ET voltages. As a result, it may be possible to employ a single ET integrated circuit (ETIC) to provide the ET voltages, thus helping to reduce cost and footprint of the ET power amplifier apparatus.

Circuit for wireless communication are provided, the circuits comprising: a first quadrature hybrid having a first in port, a first iso port, a first cpl port, and a first thru port; a first mixer having a first input coupled to the first cpl port and having an output; a second mixer have a first input coupled to the first cpl port and having an output; a third mixer having a first input coupled to the first thru port and having an output; a fourth mixer having a first input coupled to the first thru port and having an output; and a first complex combiner having inputs coupled to the output of the first mixer, the output of the second mixer, the output of the third mixer, and the output of the fourth mixer that provides first I and Q outputs based the output of the first mixer and the output of the second mixer.

Described herein are systems and methods that manage polarization in coherent optical receivers by using analog signal processing that eliminates the need for ultra-fast, power-hungry ADCs and DSPs and that would require digitization of the full-bandwidth signal path and result in bulky and expensive circuit designs. Various embodiments of the invention provide polarization correction by using an analog polarization correction circuit that implements the equivalent of two matrix operations. This is accomplished by using analog electronics that comprises a combination of variable and unity gain amplifiers to align polarizations of input signals to generate a polarization-corrected output signal that is further aligned with the polarization frame of reference of the receiver.

An active digital electronic tuner (AET) uses a digital PIN diode electronic tuner, an adjustable directional coupler, two circulators and a power amplifier to create a compact load pull tuner device able of generating octave frequency band virtual reflection factors |Gamma|1 at milli-second tuning speed.

An electronic device is disclosed. The electronic device may include an antenna for transmitting and receiving a signal in an RF frequency band, and an RF circuit for processing the signal in the RF frequency band. The RF circuit may include an Rx path for transferring a first signal received through the antenna, a Tx path for transferring a second signal output from an amplifier to the antenna, and a coupler for transferring at least a part of the second signal obtained in the Tx path to the Rx path. In addition, various embodiments understood from the specification are possible.

System and method for efficient operation of power amplifiers in dynamic carrier systems. In one example, the method includes determining a composite RMS power and peak power for a carrier configuration of an RF transmitter, determining a number of active banks of power amplifiers as a function of composite RMS power and peak power, and determining a number of active power amplifiers within a bank of power amplifiers as a function of composite RMS power and peak power. The method also includes activating a first bank of power amplifiers and/or a second bank of power amplifiers based on the determined number of active banks of power amplifiers and activating a subset of a one or more first power amplifiers of the first bank of power amplifiers and a one or more second power amplifiers of the second bank of power amplifiers based on the determined number of active power amplifiers.

The present invention relates to a four-way Doherty amplifier. The invention further relates to a mobile telecommunications base station. The invention proposes a new Doherty combiner topology that allows peak efficiencies to be reached at deeper back-off levels than conventional Doherty combiners.

Beamforming channels of a satellite are calibrated using a low power, spread spectrum calibration signal. The power of the calibration signal is below the noise level of a user signal in an active channel, allowing channels to be calibrated while active. When calibrating the transmit side circuitry, a two-stage calibration can be used, first calibrating the output hybrid matrix, then calibrating the whole of the transmit side. To improve performance, the dwell time spend calibrating a channel can be based on the power of the user signal in the channel. A transmit probe can be used to inject a calibration signal into the receive antennae and a receive probe can be used to extract the calibration signal from the transmit antennae. To reduce frequency of calibrations, the calibrations can be based on path-to-path differences. These techniques are also applied to multiport amplifiers (MPAs).