Skyworks Solutions, Inc.

Yu Zhu

Paul T DiCarlo

Oleksiy Klimashov

Dylan Charles Bartle

Florinel G Balteanu

Ambarish Roy

Guillaume Alexandre Blin

Steven Christopher Sprinkle

David Scott Whitefield

Jerod F Mason

Boshi Jin

Hanching Fuh

Fikret Altunkilic

Hailing Wang

Haki Cebi

Dima Prikhodko

Gene A Tkachenko

Sergey Nabokin

Christophe Masse

Richard A Carter

Jason Chiesa

Cejun Wei

Beverly A Peluso

Stephen Joseph Kovacic

Circuits, systems, and methods to compensate for non-linearities associated with a switching circuit are discussed herein. For example, a switch circuit can include a switch arm and a linearizer arm. The switch arm can have a first transistor connected between an input node and an output node. The switch arm can be configured to receive a radio-frequency signal. The linearizer arm can have a second transistor connected to at least one of a gate or a body of the first transistor. The linearizer arm can be configured to compensate a non-linearity effect generated by the switch arm.

Switch with gate or body connected linearizer

The present disclosure relates to a radio frequency circuit comprising a linearizer circuit. The linearizer circuit may comprise a first capacitor and a second capacitor arranged in parallel. The first capacitor may have a positive third order derivative of charge with respect to voltage. The second capacitor may have a negative third order derivative of charge with respect to voltage. Related radio frequency modules and wireless communication devices are also disclosed.

Radio frequency circuit having a linearizer

Apparatus and methods for antenna arrays for beamforming are disclosed. In certain embodiments, a mobile device includes a front-end system including a plurality of radio frequency signal conditioning circuits, an antenna array including a plurality of controllable antennas each connected to a corresponding one of the plurality of radio frequency signal conditioning circuits, and a control circuit. The plurality of controllable antennas include a first controllable antenna including a plurality of antenna elements interconnected by a plurality of variable resistors. Additionally, the control circuit is configured to control the plurality of variable resistors to control an antenna characteristic of the first controllable antenna.

Antenna array with antenna elements interconnected by controllable resistances

Apparatus and methods for envelope controlled radio frequency (RF) switches are provided. In certain embodiments, a power amplifier provides an RF signal to an antenna by way of an RF switch. Additionally, the envelope signal is used not only to control a power amplifier supply voltage of the power amplifier, but also to control a regulated voltage used to turn on the RF switch. For example, a level shifter can use a regulated voltage from charge pump circuitry to turn on the RF switch, and the envelope signal can be provided to the charge pump circuitry and used to control the voltage level of the regulated voltage over time.

Envelope controlled radio frequency switches

Described herein are switches with asymmetrical anti-series varactor pairs to improve switching performance. The disclosed switches can include asymmetrical varactor pairs to reduce distortions. The asymmetry in the varactor pairs can be associated with geometry of each varactor in the pair. The disclosed switches can stack both symmetrical and asymmetrical varactor pairs. The disclosed switches with asymmetrical anti-series varactor pairs can be configured to improve both Hand Hsimultaneously.

Switch linearization with asymmetrical anti-series varactor pair

Apparatus and methods for envelope alignment calibration in radio frequency (RF) systems are provided. In certain embodiments, calibration is performed by providing an envelope signal that is substantially triangular along an envelope path, and by providing an RF signal to a power amplifier along an RF signal path. Additionally, an output of the power amplifier is observed to generate an observation signal using an observation receiver. The observation signal includes a first peak and a second peak, and a delay between the envelope signal and the RF signal is controlled based on relative size of the peaks of the observation signal to one another.

Envelope alignment calibration in radio frequency systems

Described herein are switches with asymmetrical anti-series varactor pairs to improve switching performance. The disclosed switches can include asymmetrical varactor pairs to reduce distortions. The asymmetry in the varactor pairs can be associated with geometry of each varactor in the pair. The disclosed switches can stack both symmetrical and asymmetrical varactor pairs. The disclosed switches with asymmetrical anti-series varactor pairs can be configured to improve both H2 and H3 simultaneously.

Apparatus and methods for envelope alignment calibration in radio frequency (RF) systems are provided. In certain embodiments, calibration is performed by providing an envelope signal with a peak along an envelope path, and by providing an RF signal with a first peak and a second peak to a power amplifier along an RF signal path. Additionally, an output of the power amplifier is observed to generate an observation signal using an observation receiver. The observation signal includes a first peak and a second peak corresponding to the first peak and the second peak of the RF signal, and a delay between the envelope signal and the RF signal is controlled based on relative size of the peaks of the observation signal to one another.

A switch fabrication method can include forming a plurality of elements, and connecting the elements in series between a first terminal and a second terminal, such that the elements include a first end element connected to the first terminal and a second end element connected to the second terminal. Each element can have a parameter such that the elements have a distribution of parameter values that decreases from the first end element for at least half of the elements to a minimum parameter value corresponding to an element between the first end element and the second end element. The minimum parameter value can be less than the parameter value of the second end element, and the parameter value of the first end element can be greater than or equal to the parameter value of the second end element.

Radio-frequency switch having stack of non-uniform elements

Envelope tracking can be employed to reduce power consumption of a power amplifier, but envelope tracking can introduce nonlinearities to a power amplifier. These nonlinearities can manifest themselves as noise at the output of the power amplifier. Embodiments described herein provide techniques for characterizing a parameter indicative of power amplifier noise when envelope tracking is employed. Measurement of this parameter can permit power amplifier designers to decide whether to forgo envelope tracking if a power amplifier is too susceptible to such noise, redesign the power amplifier to improve compatibility with envelope tracking, or to employ distortion compensation circuitry to reduce the noise output by the power amplifier. Counterintuitively, this distortion compensation circuitry may involve increasing the power, such as the envelope tracking power supply. However, increasing the power may be a desirable trade-off for increased linearity.

Power amplifier linearization system and method

pHEMT-based switch circuits, devices including same, and methods of improving the linearity thereof. In one example, an antenna switch module includes a pHEMT switching circuit connected in series between an input signal terminal and a load terminal, the pHEMT switching circuit including at least one pHEMT configured to produce a first harmonic signal at the load terminal responsive to being driven by an input signal of a fundamental frequency received at the input signal terminal, the first harmonic signal having a first phase, and a gate resistance circuit connected to a gate of the at least one pHEMT and having a resistance value selected to produce a second harmonic signal at the load terminal, the second harmonic signal having a second phase opposite to the first phase.

pHEMT switch circuits with enhanced linearity performance

A linearization circuit that reduces intermodulation distortion in an amplifier output receives a first signal that includes a first frequency and a second frequency and generates a difference signal having a frequency approximately equal to the difference of the first frequency and the second frequency. The linearization circuit generates an envelope signal based at least in part on a power level of the first signal and adjusts a magnitude of the difference signal based on the envelope signal. When the amplifier receives the first signal at an input terminal and the adjusted signal at a second terminal, intermodulation between the adjusted signal and the first signal cancels at least a portion of the intermodulation products that result from the intermodulation of the first frequency and the second frequency.

Amplifier linearization in a radio frequency system

A linearization circuit reduces intermodulation distortion in an amplifier that includes a first stage and a second stage. The linearization circuit receives a first signal that includes a first frequency and a second frequency and generates a difference signal having a frequency approximately equal to the difference of the first frequency and the second frequency, generates an envelope signal based at least in part on a power level of the first signal, and adjusts a magnitude of the difference signal based on the envelope signal. When the amplifier receives the first signal at an input terminal, the first stage receives the adjusted signal, and the second stage does not receive the adjusted signal, intermodulation between the adjusted signal and the first signal cancels at least a portion of the intermodulation between the first frequency and the second frequency from the output of the amplifier.

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Wellesley, MA, United States of America

Yu Zhu