A wireless electric field power transmission system comprises: a transmitter comprising a transmitter antenna, the transmitter antenna comprising at least two conductors defining a volume therebetween; and at least one receiver, wherein the transmitter antenna transfers power wirelessly via electric field coupling when the at least one receiver is within the volume.

A radio-frequency power amplifier with envelope tracking, having a power RF amplifying device for amplifying a RF signal and a switching DC/DC converter for providing the power RF amplifying device with a DC power supply at a voltage level (VSUPP) proportional to an envelope of the RF signal, wherein the switching DC/DC converter has a reversed buck topology. Advantageously the switching device is a N-type GaN Field Effect Transistor having its drain connected to the ground.

Systems and method for improving operation of a radio frequency system are provided. One embodiment includes instructions to execute a coarse calibration to associate a first output power with a first operational parameter set; instruct the radio frequency system to transmit a signal based at least in part on the first operational parameter set and a base detrough function; determine performance metrics resulting from transmission of the signal; determine changes in the performance metrics resulting from operating the radio frequency based at least in part on the first operational parameter set and each of a plurality of augmented detrough functions; and associate a second operational parameter set with a second output power, in which the second operational parameter set includes one of the plurality of augmented detrough functions selected based at least in part on the changes that reduce margin between the performance metrics and performance metric thresholds.

An amplifier circuitry for an envelope modulator including: a linear amplifier configured to receive an input representing an envelope of a signal to be amplified; a charge storage device coupled to the amplifier for providing an amplified envelope signal for driving a load, the amplifier and charge storage device configured to receive a supply voltage; wherein the amplifier circuitry is configured such that responsive to the voltage of the input envelope signal reaching or exceeding a defined threshold value, an input voltage based on the voltage of the received envelope signal is provided to the amplifier to enable the charge storage device to supply a charge above the supply voltage such that the output voltage of the load driven by the amplifier circuitry is increased above the supply voltage. An envelope modulator incorporates the modulator and a method for amplifying an envelope signal utilizes the modulator.

Various methods and circuital arrangements for biasing one or more gates of stacked transistors of an amplifier are presented, where the amplifier can have a varying supply voltage that varies according to a control voltage. The control voltage can be related to a desired output power of the amplifier and/or to an envelope signal of an input signal to the amplifier. Particular biasing for selectively controlling the stacked transistors to operate in either a saturation region or a triode region is also presented. Benefits of such controlling, including increased linear response of an output power of the amplifier, are also discussed.

A high power class D amplifier/modulator for use in Radio Frequency ranges that is capable of digital modulation schemes at high efficiencies is disclosed. The new amplifier design features an envelope tracker unit that uses digital pulse-width modulation (PWM) generation to create analog I and Q phase high voltage signal components and sign bits. The I and Q phase signal components and sign bits are fed into an Fs/4 modulator stage to produce an analog output that is an high power RF signal modulated by the analog input signal.

Embodiments of the present disclosure a digital predistortion system and method based on envelope tracking, and a radio frequency system, so as to reduce complexity of the digital predistortion system based on envelope tracking. The system includes: a digital predistorter, a digital-to-analog converter, a frequency mixer, a power amplifier, and a power supply apparatus; where a value range of a predistortion signal that is obtained when the digital predistorter uses a first processing manner is within a first interval, and in this case, a value of a supply voltage generated by the power supply apparatus is a constant; a value range of the predistortion signal that is obtained when the digital predistorter uses a second processing manner is within a second interval, and in this case, a change of the supply voltage generated by the power supply apparatus tracks a change of an envelope signal of the predistortion signal.

A high-frequency signal processing apparatus and a wireless communication apparatus can achieve a decrease in power consumption. For example, when an indicated power level to a high-frequency power amplifier is equal to or greater than a second reference value, envelope tracking is performed by causing a source voltage control circuit to control a high-speed DCDC converter using a detection result of an envelope detecting circuit and causing a bias control circuit to indicate a fixed bias value. The source voltage control circuit and the bias control circuit indicate a source voltage and a bias value decreasing in proportion to a decrease in the indicated power level when the indicated power level is in a range of the second reference value to the first reference value, and indicate a fixed source voltage and a fixed bias value when the indicated power level is less than the first reference value.

An RF transmitter arrangement using analog pre-distortion is disclosed. The arrangement includes lower bandwidth circuitry, an analog pre-distorter, and a non-linear amplifier chain. The lower bandwidth circuitry is configured to generate an analog signal. The analog pre-distorter is configured to apply a non-linear distortion to the analog original signal based on a coupled feedback signal in order to generate an RF output signal. The non-linear amplifier chain is configured to amplify the RF output signal to generate a transmission signal relative to the analog original signal. The coupled feedback signal is derived from the transmission signal.

A radio frequency amplification stage comprising: an amplifier for receiving an input signal to be amplified and a power supply voltage; and a power supply voltage stage for supplying said power supply voltage, comprising: means for providing a reference signal representing the envelope of the input signal; means for selecting one of a plurality of supply voltage levels in dependence on the reference signal; and means for generating an adjusted selected power supply voltage, comprising an ac amplifier for amplifying a difference between the reference signal and one of the selected supply voltage level or the adjusted selected supply voltage level, and a summer for summing the amplified difference with the selected supply voltage to thereby generate the adjusted supply voltage.