Abstract: A radio frequency circuit assembly architecture is disclosed. An example radio frequency circuit assembly architecture comprises a signal contact and an antenna contact, a power amplifier module connected in a signal path between the signal contact and the antenna contact, the signal path between the power amplifier module and the antenna contact including a differentially signaled portion having a first path and a second path, and a pair of band pass filters, a first band pass filter of the pair of band pass filters being connected in the first path of the differentially signaled portion and a second band pass filter of the pair of band pass filters being connected in the second path of the differentially signaled portion.

Abstract: A radio frequency circuit includes a transmit power amplifier, a differential transmit signal path having first and second paths, and first and second baluns. The first balun can be configured to convert a single ended transmit signal into a differential transmit signal, and the second balun can be configured to convert the differential transmit signal back to a single ended transmit signal. The circuit can also include a pair of transmit filters between the first and second baluns and including a first transmit filter connected in the first path and a second transmit filter connected in the second path. The second balun cancels harmonic noise generated by the pair of transmit filters.

Abstract: A front-end module including a power amplifier, first and second couplers, an antenna switch, and a switch sub-assembly. The power amplifier has an input to receive a radio frequency signal and an output to provide an amplified radio frequency signal. The first coupler has an input port coupled to the output of the power amplifier, an output port coupled to an input of the antenna switch, a coupled port, and an isolated port. The second coupler has an input port coupled to an output of the antenna switch, an output port coupled to an antenna port, a coupled port, and an isolated port. The switch sub assembly connects one of the coupled port and the isolated port of the second coupler to an output of the switch assembly and the other one of the coupled port and the isolated port of the second coupler to a first termination impedance.

Abstract: The radio frequency front-end systems herein include modules having bandwidth controllable components, such as amplifier and filters. By implementing the modules with bandwidth control, the same module can be used for operation of multiple frequency bands including a first frequency band and a second frequency band. Thus, when implementing features such as carrier aggregation, multiple-input multiple-output (MIMO), and/or sounding resource signaling (SRS) for supporting the multiple frequency bands, the total number of modules used can be reduced and/or additional feature support can be provided compared to an implementation in which each module supports a single frequency band.

Abstract: Remote compensators for mobile devices are provided. In certain embodiments, a remote compensator includes a first balun, a cable-side circulator including an output that provides a transmit signal and an input that receives an amplified receive signal, a first phase shifter, a second phase shifter, a first antenna-side circulator, a second antenna-side circulator, a push-pull amplifier, and a receive amplifier that generates the amplified receive signal by amplifying a first receive signal from the first antenna-side circulator and a second receive signal from the second antenna-side circulator. The push-pull amplifier includes an input that receives the transmit signal, a first output connected to a first end of a winding of the first balun through the first antenna-side circulator and the first phase shifter, and a second output connected to a second end of the winding of the first balun through the second phase shifter and the second antenna-side circulator.

Abstract: Envelope tracking systems for power amplifiers are provided herein. In certain embodiments, an envelope tracker is provided for a power amplifier that amplifies an RF signal. The envelope tracker includes a multi-level switching circuit having an output that provides an output current that changes in relation to an envelope signal indicating an envelope of the RF signal when the envelope tracker is operating in an envelope tracking mode. The multi-level switching circuit includes a multi-level supply (MLS) modulator that receives multiple regulated voltages of different voltage levels, and an MLS control circuit that controls the selection of the MLS modulator over time based on the envelope signal. When transitioning the MLS modulator from selection of one regulated voltage level to another regulated voltage level, the MLS control circuit provides a soft transition to gradually switch the regulated voltage levels.

Abstract: Aspects of the disclosure include a die and corresponding radio-frequency module and wireless mobile device. Examples of the die include, integral to the die, a power amplifier controller, a low noise amplifier, and an antenna switch in communication with both the power amplifier controller and the low noise amplifier.

Abstract: Distributed radio frequency (RF) communication systems for automotive are disclosed herein. In certain embodiments, an RF communication system for an automobile includes an RF module located close to an antenna to satisfy a specified output power with small insertion loss. Additionally, the baseband processor is placed remotely from the RF module in a different area of the automobile to provide a lower temperature environment. Additionally, the RF module communicates with the baseband processor in a digital format eliminating the need for higher cost cabling (for instance, due to higher noise immunity arising from using digital signaling) and using digital transfer cabling, which can already be present in the automobile for other purposes. The RF module can include an RF front-end (RFFE) and a transceiver used for providing frequency conversion, for instance, between RF and baseband.

Abstract: Radio frequency (RF) communication systems with interference cancellation for coexistence are provided herein. In certain embodiments, an RF communication system includes a transmitter that transmits a transmit signal through a first front end system, a receiver that processes a receive signal from a second front end system, and an interference cancellation circuit that generates an interference cancellation signal that compensates the receiver for interference arising from the transmitter. The interference cancellation circuit includes a filter for filtering the transmit signal, a controllable phase circuit for adjusting a phase of the interference cancellation signal, and a controllable gain circuit for adjusting a gain of the interference cancellation signal.

Abstract: Radio frequency (RF) communication systems with interference cancellation for coexistence are provided herein. In certain embodiments, an RF communication system includes a transmitter including a power amplifier that amplifies an RF transmit signal to generate an amplified RF transmit signal, a receiver including a low noise amplifier (LNA) that amplifies an RF receive signal, and an interference cancellation circuit. The interference cancellation circuit includes a filter that generates an analog interference cancellation signal based on filtering the amplified radio frequency transmit signal, a controllable phase circuit that provides a phase adjustment to the analog interference cancellation signal, and a controllable gain circuit that provides a gain adjustment to the analog interference cancellation signal. The interference cancellation circuit injects the analog interference cancellation signal into the LNA to compensate the receiver for interference arising from the transmitter.

Abstract: Architectures and techniques relate to ganged and switch combined systems for satellite-navigation-band filters. For example, a system can include a mid-range-band filter, a satellite-navigation-band filter, and circuitry configured to receive a signal from an antenna and route the signal to the mid-range-band filter and the satellite-navigation-band filter. The circuitry can be implemented in at least one of (i) a ganged configuration in which the mid-range-band filter and the satellite-navigation-band filter receive the signal through a common input node or (ii) a switch-combined configuration in which two or more switch arms are configured to be controlled simultaneously to route the signal to the mid-range-band filter and the satellite-navigation-band filter.

Abstract: Envelope tracking systems for power amplifiers are provided herein. In certain embodiments, an envelope tracker is provided for a power amplifier that amplifies an RF signal. The envelope tracker includes an error amplifier that controls a voltage level of a power amplifier supply voltage of the power amplifier based on amplifying a difference between a reference signal and an envelope signal indicating an envelope of the RF signal. The envelope tracker further includes a multi-level switching circuit that generates an error amplifier supply voltage based on sensing a current of the error amplifier, and uses the error amplifier supply voltage to power the error amplifier.

Abstract: Apparatus and methods for signal conditioning of radio frequency signals are provided. In certain embodiments, a mobile device includes a transceiver configured to output a differential transmit signal and to receive a single-ended receive signal, and a front end system. The front end system includes a transmit balun, a differential transmit amplifier configured to amplify the differential transmit signal to generate an amplified differential transmit signal provided to a first winding of the transmit balun, a differential receive amplifier configured to amplify a differential receive signal received from the first winding to generate an amplified differential receive signal, and a receive balun configured to convert the amplified differential receive signal into the single-ended receive signal.

Abstract: Aspects of this disclosure relate to a multiplexer that includes a switchable acoustic wave filter. The switchable acoustic wave filter can include one or more acoustic wave resonators, switchable acoustic wave resonators, and a switch configurable into at least a first state and a second state. The switch can select a different subset of the switchable acoustic wave resonators to filter a radio frequency signal together with at least the one or more acoustic wave resonators in the first state than in the second state. Related filters, radio frequency systems, wireless communication devices, and methods are also disclosed.

Abstract: Aspects of this disclosure relate to a switchable acoustic wave filter. The switchable acoustic wave filter can include a switch configured to electrically connect an acoustic wave resonator to a node in a first state and to electrically isolate the acoustic wave resonator from the node in a second state. The switchable acoustic wave filter can filter a radio frequency signal with at least the acoustic wave resonator and a second acoustic wave resonator in the first state. The switchable acoustic wave filter can filter the radio frequency signal with at least the second acoustic wave resonator in the first state. Related multiplexers, radio frequency systems, wireless communication devices, and methods are also disclosed.

Abstract: Remote compensators for mobile devices are provided. In certain embodiments, a mobile device includes a cable-side circulator, an antenna, receive amplifier circuitry that amplifies a receive signal from the antenna and provides an amplified receive signal to the cable-side circulator, transmit amplifier circuitry that amplifies a transmit signal from the cable-side circulator, and a first antenna-side circulator and a second antenna-side circulator each coupled between the transmit amplifier circuitry and the antenna. The first antenna-side circulator and the second antenna-side circulator operate to compensate the receive signal for transmit leakage arising from the transmit amplifier circuitry.

Abstract: Radio frequency (RF) communication systems with dynamic waveform control and power boost are provided herein. In certain embodiments, an RF communication system includes a power amplifier configured to amplify an RF signal to generate an RF transmit signal for transmission over a time-division duplex (TDD) communication link having a duty cycle, and a transmitter configured to provide the RF signal to the power amplifier. The transmitter is operable to change a type of waveform of the RF signal from a first waveform type to a second waveform type in response to a decrease in a signal-to-noise ratio (SNR) of the TDD communication link, and to boost a power of the RF transmit signal by an amount based on the duty cycle.

Abstract: Envelope tracking systems for power amplifiers are provided herein. In certain embodiments, an envelope tracker is provided for a power amplifier that amplifies an RF signal. The envelope tracker includes an error amplifier that controls a voltage level of a power amplifier supply voltage of the power amplifier based on amplifying a difference between a reference signal and an envelope signal indicating an envelope of the RF signal. The envelope tracker further includes a multi-level switching circuit that generates an error amplifier supply voltage based on sensing a current of the error amplifier, and uses the error amplifier supply voltage to power the error amplifier.

Abstract: Reconfigurable patch antenna systems are provided herein. In certain embodiments, a mobile device includes a patch antenna configured to handle a radio frequency signal at a signal feed. The patch antenna includes a plurality of antenna segments. The front-end system further includes a plurality of switches each configured to control connection of a respective one of the first plurality of antenna segments to the first signal feed, and a control circuit configured to control the plurality of switches to provide a frequency adjustment to the patch antenna.

Abstract: A switching circuit comprises a first filter, a second filter and a plurality of switches. The first filter is configured to filter a first frequency band, a second frequency band that is adjacent to the first frequency band and a gap band between the first frequency band and the second frequency band. The second filter is configured to filter the second frequency band. The plurality of switches is configured to route signals from an antenna through one of the first filter and second filter.