A transmitting device including: a modem configured to generate a baseband signal and an envelope data corresponding to the baseband signal; a supply modulator including a first switched-mode power supplier and a second switched-mode power supplier, the supply modulator configured to provide a modulated voltage to an output node based on the envelope data; and a power amplifier configured to amplify a carrier wave signal by using the modulated voltages, the carrier wave signal being associated with the baseband signal, wherein the first switched-mode power supplier includes: a pulse input node to receive a pulse signal generated in association with the envelope data; and a plurality of stages sequentially connected between the pulse input node and the output node, the plurality of stages configured to adjust the modulated voltage by filtering certain frequency band of the pulse signal, and the plurality of stages includes at least one variable impedance.

Spatially combining signals may include receiving a number of RF input signals at a number of RF input connectors. At least one of the RF input signals is a variable envelope signal. A variable envelope signal is converted into two or more outphased constant envelope signals. The two or more outphased constant envelope signals are amplified. The amplified outphased constant envelope signals are radiated. At a spatial combiner aperture, the radiated amplified outphased constant envelope signals are combined to create a combined signal. The combined signal is output onto an output RF connector.

Spatially combining signals may include receiving a number of RF input signals at a number of RF input connectors. At least one of the RF input signals is a variable envelope signal. A variable envelope signal is converted into two or more outphased constant envelope signals. The two or more outphased constant envelope signals are amplified. The amplified outphased constant envelope signals are radiated. At a spatial combiner aperture, the radiated amplified outphased constant envelope signals are combined to create a combined signal. The combined signal is output onto an output RF connector.

An envelope tracking current bias circuit of a power amplifier circuit including a power amplifier includes a first current source circuit configured to generate a first bias current based on a reference voltage, a second current source circuit configured to generate a second bias current based on an envelope voltage of an input signal, and a bias current generator configured to generate a first envelope tracking bias current based on the first bias current and the second bias current, and supply the first envelope tracking bias current to the power amplifier circuit to reduce amplitude modulation-phase modulation (AM-PM) distortion of the power amplifier circuit.

A power amplifier bias circuit with embedded envelope detection includes a bias circuit stage coupled to an envelope detector circuit to increases a bias provided to a power amplifier as a function of an incoming envelope signal. The envelope detector circuit includes a first source/emitter follower transistor, a current source, and a filter to generate a baseband envelope signal. The current source is coupled to an output node of the first source/emitter follower transistor and the filter is also coupled to the output node of the first source/emitter follower transistor. The bias circuit stage includes one or more replica transistors that replicate transistors of the power amplifier or power amplifier core stage, an envelope detector replica transistor and a replica of the current source of the envelope detector circuit.

Control systems and methods for power amplifiers operating in envelope tracking mode are presented. A set of corresponding functions and modules are described and various possible system configurations using such functions and modules are presented.

An envelope detecting circuit is for generating an envelope signal of an input RF signal described. The envelope detecting circuit includes an input terminal, an output terminal, a transistor, and an integrating circuit. The transistor, which is operated in the class B or the class C mode, receives the input RF signal from the input terminal, amplifies the input RF signal, and outputs an amplified signal. The integrating circuit, which is provided between the transistor and the output terminal, provides a series circuit of a resistor and a capacitor between the bias supply and the ground. The transistor receives the bias through the resistor. The capacitor holds bottom levels of the amplified signal.

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.

Spatially combining signals may include receiving a number of RF input signals at a number of RF input connectors. At least one of the RF input signals is a variable envelope signal. A variable envelope signal is converted into two or more outphased constant envelope signals. The two or more outphased constant envelope signals are amplified. The amplified outphased constant envelope signals are radiated. At a spatial combiner aperture, the radiated amplified outphased constant envelope signals are combined to create a combined signal. The combined signal is output onto an output RF connector.

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.