Abstract: Embodiments of radio frequency (RF) systems include a plurality of power amplifiers having a primary winding and a secondary winding. Each of the power amplifiers may be configured to process signals of different frequency bands. The primary winding for one power amplifier can be detuned while another power amplifier is being used in a transmit mode. By detuning the power amplifier, power coupling from the transmitting power amplifier can be reduced or eliminated.

Abstract: Embodiments of radio frequency (RF) systems include a plurality of power amplifiers having a primary winding and a secondary winding. Each of the power amplifiers may be configured to process signals of different frequency bands. The primary winding for one power amplifier can be detuned while another power amplifier is being used in a transmit mode. By detuning the power amplifier, power coupling from the transmitting power amplifier can be reduced or eliminated.

Abstract: Embodiments of radio frequency (RF) systems include a plurality of power amplifiers having a primary winding and a secondary winding. Each of the power amplifiers may be configured to process signals of different frequency bands. The primary winding for one power amplifier can be detuned while another power amplifier is being used in a transmit mode. By detuning the power amplifier, power coupling from the transmitting power amplifier can be reduced or eliminated.

Abstract: Embodiments of radio frequency (RF) systems include a plurality of power amplifiers having a primary winding and a secondary winding. Each of the power amplifiers may be configured to process signals of different frequency bands. The primary winding for one power amplifier can be detuned while another power amplifier is being used in a transmit mode. By detuning the power amplifier, power coupling from the transmitting power amplifier can be reduced or eliminated.

Abstract: A high power tunable capacitor is disclosed. In an exemplary embodiment, an apparatus includes a capacitor coupled to an input signal, a body contacted switch coupled to the capacitor, the body contacted switch coupled to a body bias signal, and a floating body switch coupled between the body contacted switch and a ground, the floating body switch configured to decouple the body bias signal from the ground.

Abstract: A high power tunable capacitor is disclosed. In an exemplary embodiment, an apparatus includes a capacitor coupled to an input signal, a body contacted switch coupled to the capacitor, the body contacted switch coupled to a body bias signal, and a floating body switch coupled between the body contacted switch and a ground, the floating body switch configured to decouple the body bias signal from the ground.

Abstract: A power amplifier system can include a plurality of driver amplifiers and a plurality of power amplifiers, where each driver amplifier and power amplifier includes at least one respective input port and at least one respective output port. The power amplifier system also includes a shared inductive device that provides common interstage matching between the respective output ports of the plurality of driver amplifiers and the respective input ports of the plurality of power amplifiers. The shared inductive device can be a shared inductor or a shared transformer.

Abstract: Systems and methods are provided for a transformer or balun function with reference enhancement. The systems and methods may include a transformer having at least a primary winding and a secondary winding for reference enhancement, where the primary winding includes a center tap, where the secondary winding includes a first port and a second port, and an electrical connection that electrically connects the second port and the center tap of the primary winding to provide a common reference for the primary winding and the secondary winding. The primary winding of the transformer may be configured to receive differential outputs of a power amplifier, and the transformer may be configured to convert the differential outputs from a balanced signal to an unbalanced signal available at the first port of the secondary winding.

Abstract: Systems and methods for providing a self-mixing adaptive bias circuit that may include a mixer, low-pass filter or a phase shifter, and a bias feeding block. The self-mixing adaptive bias circuit may generate an adaptive bias signal depending on input signal power level. As the input power level goes up, the adaptive bias circuit increases the bias voltage or bias current such that the amplifier will save current consumption at low power operation levels and obtain better linearity at high power operation levels compared to conventional biasing techniques. Moreover, the adaptive bias output signal can be used to cancel the third-order intermodulation terms (IM3) to further enhance the linearity as a secondary effect.

Abstract: A SPDT or SPMT switch may include a transformer having a primary winding and a secondary winding, where a first end of the secondary winding is connected to a single pole port, where a first end of the primary winding is connected to a first throw port; a first switch having a first end and a second end, where the first end is connected to ground; and a second switch, where a second end of the secondary winding is connected to both a second end of the first switch and a first end of the second switch, where a second end of the second switch is connected to a second throw port, where the first switch controls a first communication path between the single pole port and the first throw port, and where the second switch controls a second communication path between the second throw port and the single pole port.

Abstract: A power amplifier system can include a plurality of driver amplifiers and a plurality of power amplifiers, where each driver amplifier and power amplifier includes at least one respective input port and at least one respective output port. The power amplifier system also includes a shared inductive device that provides common interstage matching between the respective output ports of the plurality of driver amplifiers and the respective input ports of the plurality of power amplifiers. The shared inductive device can be a shared inductor or a shared transformer.

Abstract: Systems and methods are provided for a transformer or balun function with reference enhancement. The systems and methods may include a transformer having at least a primary winding and a secondary winding for reference enhancement, where the primary winding includes a center tap, where the secondary winding includes a first port and a second port, and an electrical connection that electrically connects the second port and the center tap of the primary winding to provide a common reference for the primary winding and the secondary winding. The primary winding of the transformer may be configured to receive differential outputs of a power amplifier, and the transformer may be configured to convert the differential outputs from a balanced signal to an unbalanced signal available at the first port of the secondary winding.

Abstract: Systems and methods are provided for positive and negative feedback of cascode transistors for a power amplifier. The systems and methods may include a first cascode stage comprising a first common-source device and a first common-gate device; a second cascode stage comprising a second common-source device and a second common-gate device; a first degenerative element or block provided for the first common-source device; a second degenerative element or block provided for the second common-source device; a first positive feedback block or element that connects a first gate of the first common-source device with a second drain of the second common-source device; and a second positive feedback block or element that connects a second gate of the second common-source device with a first drain of the first common-source device.

Abstract: An integrated power amplifier can include a carrier amplifier, where the carrier amplifier is connected to a first quarter wave transformer at the input of the carrier amplifier.

Abstract: Systems and methods are provided for power amplifiers with discrete power control. The systems and methods may include a plurality of unit power amplifiers; a plurality of primary windings, wherein each primary winding is connected to at least one respective output port of a respective one the plurality of unit power amplifiers; a secondary winding inductively coupled to the plurality of primary windings, where the secondary winding provides an overall output; a bias controller, where the bias controller provides a respective bias voltage based at least in part on a level of output power to one or more of the plurality of unit power amplifiers; and a switch controller, where the switch controller operates to activate or deactivate at least one of the plurality of unit power amplifiers via a respective control signal.

Abstract: Systems and methods for providing an adaptive bias circuit that may include a differential amplifier, low-pass filter, and common source amplifier or common emitter amplifier. The adaptive bias circuit may generate an adaptive bias output signal depending on input signal power level. As the input power level goes up, the adaptive bias circuit may increase the bias voltage or bias current of the adaptive bias output signal. A power amplifier (e.g., a differential amplifier) may be biased according to the adaptive bias output signal in order to reduce current consumption at low power operation levels.

Abstract: A power amplifier system in accordance with an example embodiment can utilize a transformer having a primary winding inductively coupled to a secondary winding, where the primary winding includes a center tap between a first port and a second port, where the secondary winding includes a third port and a fourth port, where the primary winding receives a first output from a first amplifier, where the center tap receives a second output from a second amplifier.

Abstract: Embodiments of the invention may provide for power amplifier systems and methods. The systems and methods may include a power amplifier that generates a first differential output signal and a second differential output signal, a primary winding comprised of a plurality of primary segments, where a first end of each primary segment is connected to a first common input port and a second end of each primary segment is connected to a second common input port, where the first common input port is operative to receive the first differential output signal, and where the second common input port is operative to receive the second differential output signal, and a single secondary winding inductively coupled to the plurality of primary segments.

Abstract: A SPDT or SPMT switch may include a transformer having a primary winding and a secondary winding, where a first end of the secondary winding is connected to a single pole port, where a first end of the primary winding is connected to a first throw port; a first switch having a first end and a second end, where the first end is connected to ground; and a second switch, where a second end of the secondary winding is connected to both a second end of the first switch and a first end of the second switch, where a second end of the second switch is connected to a second throw port, where the first switch controls a first communication path between the single pole port and the first throw port, and where the second switch controls a second communication path between the second throw port and the single pole port.

Abstract: Systems and methods may be provided for a power amplifier system. The systems and methods may include a plurality of power amplifiers, where each power amplifier includes at least one output port. The systems and methods may also include a plurality of primary windings each having a first number of turns, where each primary winding is connected to at least one output port of the plurality of power amplifiers, and a single secondary winding inductively coupled to the plurality of primary windings, where the secondary winding includes a second number of turns greater than the first number of turns.