A power amplifying device includes a first amplification circuit amplifying a first signal having a first frequency component and a second frequency component; a second amplification circuit amplifying a second signal received through an output node of the first amplification circuit; a filter circuit connected between a ground node of the first amplification circuit and a common ground to pass the first and second frequency components to the common ground through the ground node; and an inverting circuit that phase-inverts a signal including second harmonic components of the first and second frequency components that are received through the ground node of the first amplification circuit and provide the phase inverted signal to the output node of the first amplification circuit.

A RF-digital hybrid mode power amplifier system for achieving high efficiency and high linearity in wideband communication systems is disclosed. The present invention is based on the method of adaptive digital predistortion to linearize a power amplifier in the RF domain. The present disclosure enables a power amplifier system to be field reconfigurable and support multi-modulation schemes (modulation agnostic), multi-carriers and multi-channels. As a result, the digital hybrid mode power amplifier system is particularly suitable for wireless transmission systems, such as base-stations, repeaters, and indoor signal coverage systems, where baseband I-Q signal information is not readily available.

A RF-digital hybrid mode power amplifier system for achieving high efficiency and high linearity in wideband communication systems is disclosed. The present invention is based on the method of adaptive digital predistortion to linearize a power amplifier in the RF domain. The present disclosure enables a power amplifier system to be field reconfigurable and support multi-modulation schemes (modulation agnostic), multi-carriers and multi-channels. As a result, the digital hybrid mode power amplifier system is particularly suitable for wireless transmission systems, such as base-stations, repeaters, and indoor signal coverage systems, where baseband I-Q signal information is not readily available.

A method, system and apparatus for modelling a power amplifier and pre-distorter fed by one of a wideband signal and an intra-band carrier aggregated signal are disclosed. According to one aspect, a method includes receiving the one of the wideband signal and the intra-band carrier aggregated signal and generating a discrete base band equivalent, BBE, Volterra series based on the received signal, where the series has distortion products grouped according to determined shared kernels. The shared kernels are determined based on a transformation of a real-valued continuous-time pass band Volterra series without pruning of kernels.

Methods, systems and apparatus for modelling a power amplifier and pre-distorter fed by a multi-band signal are disclosed. According to one aspect, a method includes receiving a multi-band signal and generating a discrete base band equivalent, BBE, Volterra series based on the received multi-band signal, where the series has distortion products grouped according to determined shared kernels. The shared kernels are determined based on a transformation of a real-valued continuous-time pass band Volterra series without pruning of kernels.

A semiconductor apparatus includes a semiconductor chip including a first semiconductor layer formed over a substrate, a second semiconductor layer formed over the first semiconductor layer, and a gate electrode, a source electrode, and a drain electrode formed over the second semiconductor layer. The gate electrode is formed in a comb shape having a plurality of tooth parts. An interval between the tooth parts becomes narrower from a center part toward a peripheral part of the semiconductor chip. The source electrode is formed on one of two sides of each of the tooth parts in the gate electrode, and the drain electrode is formed on another of the two sides. The source electrodes and the drain electrodes formed between the tooth parts in the gate electrode have respective areas that are substantially the same in a plan view.

Various digital pre-distortion systems for use in transmitters are disclosed. The digital pre-distortion system comprises an observing path, which performs either undersampling or radio frequency sampling of the output of a power amplifier. Undersampling may be performed at a rate, which causes aliasing to occur in the undersampled frequency domain. Both undersampling and radio frequency sampling reduces the complexity of the digital pre-distortion system by removing any down mixing modules or anti-aliasing modules, while maintaining reasonable performance of the digital pre-distortion systems.

Method and device(s) for supporting performance of machine learning based CFR and DPD on multiple digital input signals relating to different frequency bands, respectively, in order to signal condition said signals before power amplification and subsequent transmission in said frequency bands by a wireless communication network. The device(s) obtain said multiple digital input signals as complex valued signals. The device(s) perform feature construction that takes said multiple digital input signals as input and provides constructed feature signals according to predefined constructed feature types as output. Said predefined constructed feature types relate to at least the following per complex valued sample of the obtained complex valued multiple digital input signals the real part of the sample, the imaginary part of the sample and at least one of the absolute value of the sample and the phase of the sample.

Provided a similar combination and cancellation power amplifier circuit including a combiner main circuit implemented by connecting an output of a main signal and branch similar input combination and cancellation parallel circuit or main signal and branch similar input combination and cancellation series circuit to a main power amplifier circuit. An output of a main signal and branch similar input combination combiner circuit in the main signal and branch similar input combination and cancellation parallel circuit or main signal and branch similar input combination and cancellation series circuit is connected to an input of the main power amplifier circuit, to implement a branch similar input combination and main signal combiner main circuit.