A monolithic microwave integrate circuit (MMIC) presents as a power amplifier including a 9:1 overlay transformer and artificial low impedance transmission lines. The 9:1 overlay transformer effects the output impedance thereof. The artificial low impedance transmission lines behave as inductors without occupying an amount of space equivalent to that of an inductor having similar properties as the artificial low impedance transmission line.

A power amplifier is provided having an input for receiving a signal to be amplified that is associated with a fundamental frequency. An amplifier circuit of the power amplifier includes an active device for amplifying the input signal and an output for providing the amplified signal to a load. A load network is electrically interposed between the amplifier circuit and the output and includes fundamental frequency matching circuitry which presents an optimal resistance at the fundamental frequency. The load network further includes a parallel transmission line arrangement having, at the fundamental frequency, a one-eighth wavelength short-circuited stub and a one-eighth wavelength open-circuit stub. The fundamental frequency matching circuitry and the parallel transmission line arrangement cooperate such that the load network operatively presents an optimal resistance at the fundamental frequency, an open-circuit at a second harmonic frequency and a short-circuit at a third harmonic frequency.

A high-frequency power amplifier is configured to include plural island patterns (28) in which ends thereof are arranged in the vicinity of a transmission line (23) and other ends thereof are arranged in the vicinity of an end line (24a) in a transmission line (24), a wire (30) for connecting an end of an island pattern (28) and the transmission line (23), and a wire (31) for connecting another end of the island pattern (28) and the end line (24a) of the second transmission line (24), so that a mismatch of the impedance component having a resistance component and a reactance component can be compensated for by changing the number of first connecting members and the number of second connecting members, the first and second connecting members configured to connect an island pattern (28) to the transmission lines (23) and (24).

A packaged transistor amplifier includes a package having an input lead and an output lead; a transistor stage having a plurality of unit cell transistors that are electrically coupled to the input lead in parallel, each of the unit cell transistors having an output; a first output bond pad that is coupled to a first subset of the outputs of the unit cell transistors by a first feed network; a second output bond pad that is separate from the first output bond pad, the second output bond pad coupled to a second subset of the outputs of the unit cell transistors by a second feed network; a first output bond wire coupled between the first output bond pad and the output lead; and a second output bond wire coupled between the second output bond pad and the output lead. Related design methods are also provided.

A packaged transistor amplifier includes a package having an input lead and an output lead; a transistor stage having a plurality of unit cell transistors that are electrically coupled to the input lead in parallel, each of the unit cell transistors having an output; a first output bond pad that is coupled to a first subset of the outputs of the unit cell transistors by a first feed network; a second output bond pad that is separate from the first output bond pad, the second output bond pad coupled to a second subset of the outputs of the unit cell transistors by a second feed network; a first output bond wire coupled between the first output bond pad and the output lead; and a second output bond wire coupled between the second output bond pad and the output lead. Related design methods are also provided.

A power amplifier includes a carrier amplifier that operates from when an input signal is small, a peak amplifier that starts to operate when the input signal becomes large, a phase adjusting circuit that adjusts phases of an output of the carrier amplifier and an output of the peak amplifier, an impedance transforming line that transforms a load of the carrier amplifier when the input signal is small, and has a characteristic impedance close to an optimum load impedance of the carrier amplifier, and a circuit that is arranged between the output of the carrier amplifier and the impedance transforming line and reduces an output capacitance of the carrier amplifier.

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 (N?1) number of secondary amplifiers to amplify the remaining (N?1) number of output signals, except for the one output signal, from the N number of input networks, where the amplification order of the (N?1) 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.

Spatial power-combining devices for higher frequency operation and increased bandwidth applications are disclosed. The spatial power-combining device includes a center waveguide section with a plurality of amplifier assemblies. The plurality of amplifier assemblies forms an input end and an output end, and an input inner conductor is mechanically attached to the input end, and an output inner conductor is mechanically attached to the output end. A method for joining a plurality of amplifier assemblies together to provide a center waveguide with an input end including an input connector receptacle and an output end including an output connector receptacle is also disclosed.

Antenna waveguide transitions for solid state power amplifiers (SSPAs) are disclosed. An SSPA includes a waveguide channel that is configured to propagate an input signal, such as an electromagnetic signal, from an input port to a solid state amplifier for amplification. The waveguide channel is further configured to propagate an amplified signal from the solid state amplifier to an output port. Waveguide transitions to and from the solid state amplifier are bandwidth matched to the waveguide channel. Additionally, the waveguide transitions may be thermally coupled to the waveguide channel. The waveguide transitions may include antenna structures that have a signal conductor and a ground conductor. In this manner, the SSPA may have improved broadband coupling as well as improved thermal dissipation for heat generated by the solid state amplifier.

Apparatus and methods for multi-mode power amplifiers are provided herein. In certain configurations, a wireless device includes a multi-mode power amplifier including a plurality of amplification paths electrically connected in parallel with one another. The plurality of amplification paths includes a first amplification path including an input stage of a first stage type and an output stage of a second stage type, and a second amplification path including an output stage of the second stage type. The first stage type provides non-inverting gain and the second stage type provides inverting gain. The wireless device further includes a transceiver that provides a radio frequency signal to the multi-mode power amplifier, and that operates the multi-mode power amplifier in a selected power mode chosen from a plurality of power modes based on selectively activating one or more of the plurality of amplification paths.