The outphasing power combiner circuit includes a transformer having a primary coil coupled to a first power amplifier (PA) and a second PA, and a secondary coil. The secondary coil supplies a current to an antenna based on a first direction of a first phase of a first amplified constant-envelope signal in the primary coil with respect to a second phase of a second amplified constant-envelope signal in the primary coil. The outphasing power combiner circuit further includes load impedance coupled between a median point of the primary coil and ground. The load impedance dissipates the current based on a second direction of the first phase of the first amplified constant-envelope signal in the primary coil with respect to the second phase of the second amplified constant-envelope signal in the primary coil, which results in improved power efficiency.

Methods and systems for power amplification of time varying envelope signals are disclosed herein. In one embodiment, a plurality of signals with constant envelope generated from the decomposition of the quantized version of a time varying envelope signal are individually amplified and then summed to form a desired time-varying envelope signal. Amplitude, phase and frequency characteristics of one or more of the constituent signals are controlled to provide the desired phase, frequency, and/or amplitude characteristics of the desired time varying envelope signal. In another embodiment, a time-varying envelope signal is decomposed into in-phase and quadrature components that are quantized and decomposed into a plurality of quasi constant or constant envelope constituent signals. The constituent signals are amplified, and then summed to construct an amplified version of the original time-varying envelope signal. The signal amplifiers may be Class A, B, AB, C, D, Class F or Class S amplifiers to provide high amplification efficiency.

Ringing of a signal after passing through a low pass filter in an LINC type linear amplifier is remedied. A linear amplifying device includes the linear amplifier including the low pass filter for removing high-frequency components; and an origin avoiding circuit which receives an original input signal and is provided upstream of the linear amplifier. If the original input signal is sampled in the vicinity of an origin, the origin avoiding circuit modifies a sampled value so at to replace the sampled value with a fixed value, and supplies the modified input signal to the linear amplifier.

A method and an apparatus are provided for calibrating digital pre-distortion (DPD) of an electronic device. A respective signal is received, by each of a first plurality of receiving antennas, from each of a second plurality of transmitting antennas. A DPD function is determined for each of the second plurality of transmitting antennas based on the received signals. A combined DPD function of the second plurality of transmitting antennas is determined based on the DPD functions and phase shifter settings associated with the second plurality of transmitting antennas.

Embodiments of this application disclose a signal processing circuit, a radio frequency signal transmitter, and a communications device, and relate to the field of electronic device technologies, to improve power amplification efficiency of the signal processing circuit. The signal processing circuit includes: a splitter, a radio frequency signal converter, a first branch power amplifier, a second branch power amplifier, and a combiner. The splitter is connected to the radio frequency signal converter, the radio frequency signal converter is connected to the first branch power amplifier and the second branch power amplifier, and the first branch power amplifier and the second branch power amplifier are connected to the combiner.

The present invention relates to an amplifying device and to an amplifying system comprising the same. According to the present invention, an amplifier line-up is presented comprising four amplifying units which is operable in a Doherty mode and an outphasing mode. By integration of Chireix compensating elements in the matching networks used in the amplifying units a bandwidth improvement can be obtained.

According to an aspect, there is provided a method for power-amplification of a transmission signal, comprising: obtaining the transmission signal with phase and amplitude modulation; generating a power-amplified polar signal for approximating a power-amplified transmission signal by power-amplifying a first constant-envelope signal with one of two or more first amplification factors based on the transmission signal; generating an outphasing) pair of a first power-amplified outphasing signal and a second power-amplified outphasing signal based on the transmission signal; and combining the power-amplified polar signal, the first power-amplified outphasing signal and the second power-amplified outphasing signal to provide the power-amplified transmission signal.

A circuit includes an amplifier to amplify an input signal and generate an output signal. The circuit also includes a tuning network to tune frequency response of the amplifier. The tuning network includes at least one tunable capacitor, which includes at least one micro-electro mechanical system (MEMS) capacitor. The amplifier could include a first die, the at least one MEMS capacitor could include a second die, and the first die and the second die could be integrated in a single package. The at least one MEMS capacitor could include a MEMS superstructure over a control structure, which is to control the MEMS superstructure and tune the capacitance of the at least one MEMS capacitor.

An all digital outphasing transmitter includes, at least one decomposition unit for decomposing an input signal to generate a first sub-signal and a second sub-signal; at least one outphasing signal generator to convert said first sub-signal to an outphasing signal; at least one delta sigma modulator to convert said second sub-signal to a delta sigma modulated signal; at least one mixing unit for mixing the outphasing signal and delta sigma modulated signal to generate a first and second mixed signal; at least one first amplifier for amplifying the first mixed signal; at least one second amplifier for amplifying the second mixed signal; at least one combiner for combining the first and second amplified mixed signals to generate a delta sigma modulated output signal and at least one band pass filter for filtering the delta sigma modulated output signal to recover the input signal envelope back on to the output signal.

An all digital outphasing transmitter includes, at least one decomposition unit for decomposing an input signal to generate a first sub-signal and a second sub-signal; at least one outphasing signal generator to convert said first sub-signal to an outphasing signal; at least one delta sigma modulator to convert said second sub-signal to a delta sigma modulated signal; at least one mixing unit for mixing the outphasing signal and delta sigma modulated signal to generate a first and second mixed signal; at least one first amplifier for amplifying the first mixed signal; at least one second amplifier for amplifying the second mixed signal; at least one combiner for combining the first and second amplified mixed signals to generate a delta sigma modulated output signal and at least one band pass filter for filtering the delta sigma modulated output signal to recover the input signal envelope back on to the output signal.