Abstract: Reconfigurable front-end module for carrier aggregation. In some embodiments, a front-end module can include a plurality of signal ports and a plurality of antenna ports. The front-end module can further include a switch assembly configured to route signals along one or more of a plurality of filtering paths between the signal ports and the antenna ports. Each of the filtering paths can include a filter, and the filtering paths can be configured to allow the antenna ports to be combined outside of the front-end module to accommodate a corresponding antenna configuration. The filtering paths can be further configured to maintain desirable filtering performance levels for different combinations of the antenna ports outside of the front-end module corresponding to the different antenna configurations.

Abstract: Described herein are systems, architectures, circuits, devices, and methods for a DC-DC converter that dynamically adjusts a supply voltage to a power amplifier based on the number of resource blocks in a signal to be transmitted. The disclosed technologies estimate the number of resource blocks in a signal, generate a signal corresponding to the estimated number of resource blocks, and modify a supply voltage based on the generated signal. The disclosed DC-DC converters can be integrated into systems that employ power management strategies such as average power tracking (“APT”). In addition, the disclosed technologies can be used to improve existing APT-based systems.

Abstract: Aspects of this disclosure relate to a coupler circuit configured to receive an output of a radio frequency coupler. The coupler circuit can be arranged in a daisy chain with other coupler circuits. The coupler circuit can include a switch configured to turn on based on a signal level of a direct current component of a coupler signal from another coupler circuit and pass a radio frequency component of the coupler signal when on. The coupler circuit can pass the coupler signal while a module that includes the coupler circuit is otherwise inactive.

Abstract: Apparatus and methods for envelope tracking systems are disclosed herein. In certain implementations, an envelope tracking system for generating a power amplifier supply voltage for a power amplifier is provided. The envelope tracking system includes a DC-to-DC converter that generates a regulated voltage from a battery voltage and controls a voltage of the regulated voltage using a low frequency feedback signal. The envelope tracking system further includes an error amplifier that generates an output current using an envelope signal and a high frequency feedback signal. The low frequency feedback signal is based on a low frequency component of the power amplifier supply voltage and the high frequency feedback signal is based on a high frequency component of the power amplifier supply voltage. The error amplifier generates the power amplifier supply voltage by adjusting the magnitude of the regulated voltage using the output current.

Abstract: A power amplifier that can support multiple communication networks while maintaining power efficiency across each of the supported communication networks is disclosed. In some implementations described herein, a power amplifier module includes a bypass circuit that enables different voltage supplies to be provided to the power amplifier. By regulating the voltage supply provided to the power amplifier, the power amplifier can support different communication networks while maintaining power efficiency across a dynamic frequency range. Moreover, embodiments herein may include a buck converter, or other form of DC-DC converter, that enables the power amplifier to operate with respect to multiple communication networks.

Abstract: Aspects of this disclosure relate to a coupler circuit configured to receive an output of a radio frequency coupler. The coupler circuit can be arranged in a daisy chain with other coupler circuits. The coupler circuit can include a switch configured to turn on based on a signal level of a direct current component of a coupler signal from another coupler circuit and pass a radio frequency component of the coupler signal when on. The coupler circuit can pass the coupler signal while a module that includes the coupler circuit is otherwise inactive.

Abstract: A power amplifier that can support multiple communication networks while maintaining power efficiency across each of the supported communication networks is disclosed. In some implementations described herein, a power amplifier module includes a bypass circuit that enables different voltage supplies to be provided to the power amplifier. By regulating the voltage supply provided to the power amplifier, the power amplifier can support different communication networks while maintaining power efficiency across a dynamic frequency range. Moreover, embodiments herein may include a buck converter, or other form of DC-DC converter, that enables the power amplifier to operate with respect to multiple communication networks.

Abstract: Apparatus and methods for envelope tracking systems are disclosed herein. In certain implementations, an envelope tracking system for generating a power amplifier supply voltage for a power amplifier is provided. The envelope tracking system includes a DC-to-DC converter that generates a regulated voltage from a battery voltage and controls a voltage of the regulated voltage using a low frequency feedback signal. The envelope tracking system further includes an error amplifier that generates an output current using an envelope signal and a high frequency feedback signal. The low frequency feedback signal is based on a low frequency component of the power amplifier supply voltage and the high frequency feedback signal is based on a high frequency component of the power amplifier supply voltage. The error amplifier generates the power amplifier supply voltage by adjusting the magnitude of the regulated voltage using the output current.

Abstract: A power amplifier that can support multiple communication networks while maintaining power efficiency across each of the supported communication networks is disclosed. In some implementations described herein, a power amplifier module includes a bypass circuit that enables different voltage supplies to be provided to the power amplifier. By regulating the voltage supply provided to the power amplifier, the power amplifier can support different communication networks while maintaining power efficiency across a dynamic frequency range. Moreover, embodiments herein may include a buck converter, or other form of DC-DC converter, that enables the power amplifier to operate with respect to multiple communication networks.

Abstract: Apparatus and methods for envelope tracking in a mobile device are disclosed herein. In certain configurations, a method includes amplifying a radio frequency (RF) input signal using a power amplifier, providing power to the power amplifier from a power amplifier supply voltage, controlling a voltage level of the power amplifier supply voltage based on a control voltage using a DC-to-DC converter, adjusting the voltage level of the power amplifier supply voltage based on an envelope of the RF input signal using an error amplifier, low pass filtering the power amplifier supply voltage to generate a filtered voltage using a low pass filter, and generating the control voltage based on comparing the filtered voltage to a reference voltage using a comparator.

Abstract: Current aggregation using diplexers. A multiplexing system can include a first diplexer and a second diplexer. The first diplexer can have a first transmit terminal, a first receive terminal, and a first common terminal. The first diplexer can be configured to filter a first transmit signal received at the first transmit terminal to a first cellular frequency band and output the filtered first transmit signal at the first common terminal. The first diplexer can be further configured to filter a first receive signal received at the first common terminal to a second cellular frequency band and output the filtered first receive signal at the first receive terminal input. The second diplexer can have a second transmit terminal, a second receive terminal, and a second common terminal. The second diplexer can be configured to filter a second transmit signal received at the second transmit terminal to the second cellular frequency band and output the filtered second transmit signal at the second common terminal.

Abstract: Disclosed herein are wireless transceivers with switches to reduce harmonic leakage. In some embodiments, a transmitter system includes a power amplification system including a first power amplifier configured to amplify a signal at a first cellular frequency band and a second power amplifier configured to amplify a signal at a second cellular frequency band. The transmitter includes a switch coupled between an output of the second power amplifier and a ground potential. The transmitter includes a controller configured to, based on a band select signal, control the switch and selectively enable or disable each of the first power amplifier and the second power amplifier. Selective control of the switch can reduce harmonic leakage compared to a system that does not include the disclosed switches and controls.

Abstract: Apparatus and methods for envelope tracking in a mobile device are disclosed herein. In certain configurations, a method includes amplifying a radio frequency (RF) input signal using a power amplifier, providing power to the power amplifier from a power amplifier supply voltage, controlling a voltage level of the power amplifier supply voltage based on a control voltage using a DC-to-DC converter, adjusting the voltage level of the power amplifier supply voltage based on an envelope of the RF input signal using an error amplifier, low pass filtering the power amplifier supply voltage to generate a filtered voltage using a low pass filter, and generating the control voltage based on comparing the filtered voltage to a reference voltage using a comparator.

Abstract: Apparatus and methods for envelope trackers are disclosed herein. In certain configurations, a mobile device includes a power amplifier configured to amplify a radio frequency (RF) input signal to generate an RF output signal. The power amplifier is configured to receive power from a power amplifier supply voltage. The mobile device further includes a voltage converter configured to convert a battery voltage into a regulated voltage, and the voltage converter is configured to control a magnitude of the regulated voltage based on an error signal. The mobile device further includes an error amplifier configured to generate an output current based on an envelope of the RF input signal and to generate the power amplifier supply voltage by adjusting the magnitude of the regulated voltage using the output current. The error amplifier is further configured to control the error signal.

Abstract: Circuits and methods related to radio-frequency (RF) architectures having carrier aggregation. In some implementations, a carrier aggregation (CA) architecture can include a duplexer configured to provide duplexing functionality for a first frequency band and a second frequency band with a common antenna. The CA architecture can further include a first amplification path and a second amplification path coupled to respective ports of the duplexer, each of the first amplification path and the second amplification path configured to amplify a signal in its respective frequency band, each amplification path including a transmit/receive (TX/RX) switch configured to provide time-division duplexing (TDD) functionality for the amplified signal and a received signal. In some implementations, the first frequency band includes a B39 band, and the second frequency band includes a B41 band.

Abstract: Radio frequency (RF) power amplifier (PA) circuitry and a PA envelope power supply are disclosed. The RF PA circuitry receives and amplifies an RF input signal to provide an RF output signal using an envelope power supply signal, which is provided by the PA envelope power supply. The RF PA circuitry operates in either a normal RF spectral emissions mode or a reduced RF spectral emissions mode. When reduced RF spectral emissions are required, the RF PA circuitry operates in the reduced RF spectral emissions mode. As such, at a given RF output power, during the reduced RF spectral emissions mode, RF spectral emissions of the RF output signal are less than during the normal RF spectral emissions mode. As a result, the reduced RF spectral emissions mode may be used to reduce interference between RF communications bands.

Abstract: The present disclosure relates to envelope power supply calibration of a multi-mode RF power amplifier (PA) to ensure adequate headroom when operating using one of multiple communications modes. The communications modes may include multiple modulation modes, a half-duplex mode, a full-duplex mode, or any combination thereof. As such, each communications mode may have specific peak-to-average power and linearity requirements for the multi-mode RF PA. As a result, each communications mode may have corresponding envelope power supply headroom requirements. The calibration may include determining a saturation operating constraint based on calibration data obtained during saturated operation of the multi-mode RF PA. During operation of the multi-mode RF PA, the envelope power supply may be restricted to provide a minimum allowable magnitude based on an RF signal level of the multi-mode RF PA, the communications mode, and the saturation operating constraint to provide adequate headroom.

Abstract: Radio frequency (RF) power amplifier (PA) circuitry and a PA envelope power supply are disclosed. The RF PA circuitry receives and amplifies an RF input signal to provide an RF output signal using an envelope power supply signal, which is provided by the PA envelope power supply. The RF PA circuitry operates in either a normal RF spectral emissions mode or a reduced RF spectral emissions mode. When reduced RF spectral emissions are required, the RF PA circuitry operates in the reduced RF spectral emissions mode. As such, at a given RF output power, during the reduced RF spectral emissions mode, RF spectral emissions of the RF output signal are less than during the normal RF spectral emissions mode. As a result, the reduced RF spectral emissions mode may be used to reduce interference between RF communications bands.

Abstract: Apparatus and methods for envelope tracking systems are disclosed herein. In certain implementations, an envelope tracking system for generating a power amplifier supply voltage for a power amplifier is provided. The envelope tracking system includes a DC-to-DC converter that generates a regulated voltage from a battery voltage and controls a voltage of the regulated voltage using a low frequency feedback signal. The envelope tracking system further includes an error amplifier that generates an output current using an envelope signal and a high frequency feedback signal. The low frequency feedback signal is based on a low frequency component of the power amplifier supply voltage and the high frequency feedback signal is based on a high frequency component of the power amplifier supply voltage. The error amplifier generates the power amplifier supply voltage by adjusting the magnitude of the regulated voltage using the output current.

Abstract: Apparatus and methods for envelope trackers are disclosed herein. In certain configurations, a mobile device includes a power amplifier configured to amplify a radio frequency (RF) input signal to generate an RF output signal. The power amplifier is configured to receive power from a power amplifier supply voltage. The mobile device further includes a voltage converter configured to convert a battery voltage into a regulated voltage, and the voltage converter is configured to control a magnitude of the regulated voltage based on an error signal. The mobile device further includes an error amplifier configured to generate an output current based on an envelope of the RF input signal and to generate the power amplifier supply voltage by adjusting the magnitude of the regulated voltage using the output current. The error amplifier is further configured to control the error signal.