A bandpass parametric amplifier circuit includes a plurality of unit cells. At least one unit cell includes a first inductor having a first node coupled to a center conductor and a second node coupled to ground. There is a first capacitor having a first node coupled to the center conductor and a second node coupled to ground. There is a second inductor having a first node coupled to the center conductor. A second capacitor has a first node coupled to a second node of the second inductor. The second capacitor and the second inductor are in series with the center conductor.

Amplifier circuitry is disclosed for receiving a differential signal and outputting a single-ended output signal. A travelling wave amplifier has a plurality of amplifier elements connected between an input transmission line and an output transmission line, each extending between first and second sides of the travelling wave amplifier. The input transmission line is configured to receive the first differential signal component at the first side and the output transmission line is configured to provide the single-ended output signal at the second side. A matched transmission line, which is configured to match at least some transmission properties of the input transmission line, receive the second differential signal component at the first end. A differential termination network is connected to both the input transmission line and matched and the matched transmission line and is configured to provide differential termination of signals received at the first and second termination inputs.

According to one embodiment, a low noise amplifier (LNA) circuit includes a first stage which includes: a first transistor; a second transistor coupled to the first transistor; a first inductor coupled in between an input port and a gate of the first transistor; and a second inductor coupled to a source of the first transistor, where the first inductor and the second inductor resonates with a gate capacitance of the first transistor for a dual-resonance. The LNA circuit includes a second stage including a third transistor; a fourth transistor coupled between the third transistor and an output port; and a passive network coupled to a gate of the third transistor. The LNA circuit includes a capacitor coupled in between the first and the second stages, where the capacitor transforms an impedance of the passive network to an optimal load for the first amplifier stage.

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.

Apparatus are provided for amplifier systems and related circuits are provided. An exemplary circuit includes a main amplifier arrangement, first impedance matching circuitry coupled between the output of the main amplifier arrangement and a first circuit output, a peaking amplifier arrangement, and second impedance matching circuitry coupled between the output of the peaking amplifier arrangement and a second output of the circuit. In one exemplary embodiment, the first impedance matching circuitry and the second impedance matching circuitry have different circuit topologies and different physical topologies.

According to one embodiment, a transmit/receive (T/R) switch includes a transmit switch, between a transmit port and an antenna port, a receive switch, between a receive port and the antenna port, a transmit inductor, coupled in parallel between the transmit switch the transmit port, and a receive inductor, coupled in parallel between the transmit switch the transmit port. The T/R switch can be co-designed with a power amplifier (PA) output matching circuit.

A power amplifier circuit includes external input and output terminals; a first power amplifier with first input and output terminals, the first input terminal being connected to the external input terminal, the first output terminal being connected to the external output terminal; a second power amplifier having second input and output terminals, the second input terminal being connected to the external input terminal, the second output terminal being connected to the external output terminal; a power supply terminal that receives a power supply voltage that is supplied to the first power amplifier and controllably supplied to the second power amplifier; and a switch having first and second terminals, the first terminal being connected to the power supply terminal, the second terminal being connected to the second power amplifier.

An amplifier circuit (200) for compensating an output signal provided at an output (212) of a circuit (210) is disclosed. The amplifier circuit (200) comprises an output transmission line (230) connected between the output (212) of the circuit (210) and an output port (240) and an amplifier (220). The amplifier (220) comprises multiple sub-amplifiers (221, 222, 223, 224), inputs of the multiple sub-amplifiers (221, 222, 223, 224) are coupled to an input transmission line (250) for receiving an error signal; and outputs of the multiple sub-amplifiers (221, 222, 223, 224) are coupled at respective places along the output transmission line (230) to inject a compensation signal to the output port (240). The error signal is derived from a reference input signal and the output signal of the circuit (210), and is amplified in the amplifier (220) into the compensation signal.

Aspects and examples described herein provide a radio-frequency switching circuit, switching device, and related methods. In one example, a radio-frequency switching device includes an input path configured to receive a radio-frequency signal, a plurality of output paths each configured to provide the radio-frequency signal, and a plurality of radio-frequency sub-networks each coupled to the input path and configured to direct the radio-frequency signal, each of the plurality of sub-networks including at least a first radio-frequency circuit having a first series of directly biased transistors, a second radio-frequency circuit having a second series of directly biased transistors, and a direct current blocking network interposed between the first radio-frequency circuit and the second radio-frequency circuit, each output path of the plurality corresponding to at least one of the plurality of radio-frequency sub-networks.

An embodiment of a module (e.g., an amplifier module) includes a substrate, a transmission line, and a ground plane height variation structure. The substrate is formed from a plurality of dielectric material layers, and has a mounting surface and a second surface opposite the mounting surface. A plurality of non-overlapping zones is defined at the mounting surface. The transmission line is coupled to the substrate and is located within a first zone of the plurality of non-overlapping zones. The ground plane height variation structure extends from the second surface into the substrate within the first zone. The ground plane height variation structure underlies the transmission line, a portion of the substrate is present between the upper boundary and the transmission line, and the ground plane height variation structure includes a conductive path between an upper boundary of the ground plane height variation structure and the second surface.