An amplifier package may include a transistor, an output impedance matching circuit and one or more radial stub harmonic traps coupled to a control terminal of the transistor or to an output terminal of the transistor. The output impedance matching circuit and the radial stub harmonic traps may be formed on a single substrate or separate substrates, which may be formed from gallium nitride. Each radial stub harmonic trap may provide a low resistance path to ground for signal energy above a fundamental operating frequency of the amplifier, such as harmonic frequencies thereof.

An example embodiment relates to a radiofrequency (RF) power amplifier pallet, and further relates to an electronic device that includes such a pallet. The RF power amplifier pallet may include a coupled line coupler that includes a first line segment and a second line segment that is electromagnetically coupled to the first line segment. A first end of the first line segment may be electrically connected to an output of an RF amplifying unit. The RF power amplifier pallet may further include a dielectric filled waveguide having an end section of the first dielectric substrate, an end section of the second dielectric substrate, and a plurality of metal wall segments covering the end sections of the first and second dielectric layers. The plurality of metal wall segments may be arranged spaced apart from the first line segment and electrically connected to a first end of the second line segment.

System includes first and second amplifying circuits that are configured to receive input signals having a fundamental frequency. The system also includes first and second transmission lines that are configured to receive voltage and current waveforms from the first and second amplifying circuits, respectively. The system also includes a capacitively-compensated transmission line resonator (CC-TLR) that is configured to be electrically connected to a load having a load impedance. The CC-TLR is configured to receive and combine RF power from the first and second transmission lines. The CC-TLR has a compensation capacitance that causes the CC-TLR to present an open circuit at the fundamental frequency and present a short circuit at harmonic frequencies. Optionally, a characteristic impedance (Z.sub.0) of the first and second transmission lines and a load impedance (Z.sub.L) are unequal, and the first and second transmission lines cause a load impedance transformation.

An amplifier has an N number of input networks connected to an input terminal to receive an input signal, a first amplifier to amplify one output signal from the N number of input networks, a (N1) number of secondary amplifiers to amplify the remaining (N1) number of output signals, except for the one output signal, from the N number of input networks, where the amplification order of the (N1) number of secondary amplifiers is determined based on the power level of each output signal from the N number of input networks when the first amplifier is operational, an N number of output networks which are arranged, and a first bias network to supply a D.C. bias voltage to at least one of the N number of output networks. An electrical length of the first bias network is less than 90 degrees.

An on-chip transformer circuit is disclosed. The on-chip transformer circuit comprises a primary winding circuit comprising at least one turn of a primary conductive winding arranged as a first N-sided polygon in a first dielectric layer of a substrate; and a secondary winding circuit comprising at least one turn of a secondary conductive winding arranged as a second N-sided polygon in a second, different, dielectric layer of the substrate. In some embodiments, the primary winding circuit and the secondary winding circuit are arranged to overlap one another at predetermined locations along the primary conductive winding and the secondary conductive winding, wherein the predetermined locations comprise a number of locations less than all locations along the primary conductive winding and the secondary conductive winding.

An amplifier includes amplification stages connected in parallel between an input point and an output point and a feedback circuit, wherein the amplification stages each include a transistor configured to amplify a signal supplied from the input point, a harmonic processing unit configured to process harmonics present in an amplified signal output from an output node of the transistor, a connection point between the output node and the harmonic processing unit, and a transmission line connecting the connection point and the output point, wherein the feedback circuit feeds back a signal at the output point or a midway point of the transmission line of a given one of the amplification stages to a first end of a resistor connected to the connection point of the given one of the amplification stages, a second end of the resistor being connected to the connection point of another one of the amplification stages.

A method for transforming the impedance of a radio-frequency transmission line of a printed circuit from a first impedance value to a second impedance value, the radio-frequency transmission line being adapted to transport a radio-frequency signal at a frequency value comprised in a frequency range defined between a minimum frequency value and a maximum frequency value, wherein the following steps are envisaged: dividing the radio-frequency transmission line into a plurality of circuit sections each one of the circuit sections including a first and a second impedance connected in parallel with each other by two circuit branches placed at a maximum distance (d.sub.max) from each other, wherein the circuit sections have respective third impedance values that gradually increase, respectively decrease, from the first impedance value to the second impedance value; determining the maximum distance between the circuit branches in such a way as to avoid any undesired frequency values within the frequency range; setting a fourth impedance value of one of the two impedances; calculating a fifth impedance value of the other one of the two impedances, such that the impedance value of the circuit section is the third respective impedance value.

A digital power amplifier comprising two or more individually activatable amplifiers. The outputs of the amplifiers are connected causing an activated amplifier of the two or more amplifiers to load modulate another activated amplifier of the two or more amplifiers.

A power amplifier (PA) system is provided for multi-mode multi-band operations. The PA system includes one or more amplifying modules, each amplifying module including one or more banks, each bank comprising one or more transistors; and a plurality of matching modules, each matching module being configured to be adjusted to provide impedances corresponding to frequency bands and conditions. A controller dynamically controls an input terminal of each bank and adjusts the matching modules to provide a signal path to meet specifications on properties associated with signals during each time interval.

An embodiment of an amplifier includes a first amplifier with a first output terminal, a second amplifier with a second output terminal, and a plurality of microstrip transmission lines electrically connected to the amplifiers. The transmission lines include an impedance inverter line electrically connected between the first and second output terminals, and an output line electrically connected between the second output terminal and an output of the amplifier, where the output line forms a portion of an output impedance transformer. The amplifier also includes a directional coupler formed from a main line and a coupled line positioned in proximity to the main line, where the main line is formed from a portion of one of the transmission lines. The amplifier may also include a module substrate with a plurality of metal layers, where the main line and the coupled line are formed from different portions of the metal layers.