Abstract: Systems and methods for differential antenna driving are provided. In one aspect, a front end system includes at least one power amplifier configured to receive a first transmit radio frequency signal from a baseband processor, amplify the first transmit radio frequency signal, and output the amplified first transmit radio frequency signal. The front end system further includes at least one balun configured to receive the amplified first transmit radio frequency signal. The at least one balun includes a positive output coupled to a first monopole of at least one antenna and a negative output coupled to a second monopole of the at least one antenna.

Abstract: Disclosed herein are embodiments of high Q, temperature stable materials with low dielectric constants. In particular, a two-phase material can form based on the rutile phase of titanium oxide along with a spinel structure of ZnAl2O4. This material can have a dielectric constant below 15 which is simultaneously temperature stable.

Abstract: 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.

Abstract: Systems and methods for high power uplink transmission are disclosed. In one aspect, a mobile device includes an antenna configured to transmit radio frequency signals to a base station via an uplink and receive radio frequency signals from the base station via a downlink and a front end system coupled to the antenna. The front end system is configured to transmit and receive the radio frequency signals from the antenna, and duplex the radio frequency signals via frequency division duplexing. The front end system is further configured to transmit data on the uplink at a first power level that is higher than a predetermined level and at a finite duty cycle.

Abstract: Aspects of this disclosure relate to a multi-mode power amplifier system. A first power amplifier is configured to provide a radio frequency signal associated with a different radio access technology in a first mode than in a second mode. A second power amplifier is configured to be active in the first mode such that the first power amplifier and the second power amplifier are concurrently active in the first mode. A switch can electrically connect the output of the first power amplifier to different radio frequency signal path in the first mode than in the second mode. Related methods, power amplifier modules, and wireless communication devices are disclosed.

Abstract: A front end module for a wireless device. The front end module comprises an input port to receive a first radio frequency signal, a power amplifier, an antenna port, a first transmit/receive path, a second transmit/receive path, a switch, and a switching circuit. The power amplifier is coupled to the input port and configured to amplify the first radio frequency signal. The antenna port provides the amplified first radio frequency signal to an antenna. The first transmit/receive path includes a filter, and the switch includes a first contact coupled to the first transmit/receive path, a second contact coupled to the second transmit/receive path, and a third contact coupled to the antenna port. The switching circuit is configured to selectively couple the power amplifier to the antenna port via one of the first transmit/receive path and the second transmit/receive path.

Abstract: A surface acoustic wave device is disclosed. The surface acoustic wave device can include a ceramic substrate, a piezoelectric layer over the ceramic substrate, and an interdigital transducer electrode over the piezoelectric layer. The ceramic substrate can be a polycrystalline spinel substrate. The surface acoustic wave device can also include a temperature compensating layer over the interdigital transducer electrode.

Abstract: Systems and methods for integrating injection-locked oscillators into transceiver arrays are disclosed. In one aspect, there is provided an injection-locked oscillator (ILO) distribution system including a master clock generator configured to generate a master clock signal. The ILO distribution system also includes an ILO distribution circuit including an ILO and configured to receive the master clock signal. The ILO is configured to generate a reference clock signal based on the master clock signal. The ILO distribution circuit is further configured to generate an output signal indicative of an operating frequency of the ILO. The ILO distribution system further includes an injection-locked detector (ILD) configured to receive the master clock signal and the output signal. The ILD is further configured to determine whether the ILO is in a locked state or in an unlocked state based on the master clock signal and the output signal.

Abstract: Apparatus and methods for sounding reference signal (SRS) switching are provided. In certain embodiments, a controller internal to the power amplifier module initiates a sequence of instructions, in response to a single command from UE. The instructions cause a reduction in gain of the power amplifier, and initiate a delay. The antennas switch actuates after the delay to switch from a first antenna to a second antenna. The teachings herein can be used to avoid over-power on the power amplifier and antenna switch.

Abstract: Radio frequency (RF) communication systems with coexistence management are provided herein. In certain embodiments, a method of coexistence management in a mobile device includes processing a wireless local area network (WLAN) observation signal to generate WLAN observation data using a WLAN observation channel of a WLAN transceiver, processing an RF cellular receive signal to generate a digital baseband cellular receive signal using a cellular receive channel of a cellular transceiver, processing a cellular observation signal to generate cellular observation data using a cellular observation channel of the cellular transceiver, and compensating the digital baseband cellular receive signal for RF signal leakage based on the WLAN observation data and on the cellular observation data using a discrete time cancellation circuit of the cellular transceiver.

Abstract: A laterally excited bulk acoustic wave device is disclosed. The laterally excited bulk acoustic wave device can include a first solid acoustic mirror, a second solid acoustic mirror, a piezoelectric layer that is positioned between the first solid acoustic mirror and the second solid acoustic mirror, an interdigital transducer electrode on the piezoelectric layer, and a support substrate arranged to dissipate heat associated with the bulk acoustic wave. The interdigital transducer electrode is arranged to laterally excite a bulk acoustic wave. The first solid acoustic mirror and the second solid acoustic mirror are arranged to confine acoustic energy of the bulk acoustic wave. The first solid acoustic mirror is positioned on the support substrate.

Abstract: Amplifier having electrostatic discharge and surge protection circuit. In some embodiments, a radio-frequency integrated circuit can include an amplifier, a controller configured to control operation of the amplifier, and a clamp circuit configured to provide electrostatic discharge protection and surge protection for either or both of the amplifier and the controller. The clamp circuit can include a feedback combination clamp implemented to direct a current associated with either or both of an electrostatic discharge and a surge at a first node to a second node.

Abstract: According to some aspects of this disclosure a radio frequency signal coupler is provided. The radio frequency coupler includes an input port, an output port, a main transmission line extending between the input port and the output port, a coupled transmission line electromagnetically coupled to the main transmission line, at least one coupled port coupled to the coupled transmission line, and a plurality of termination ports connected to the coupled transmission line, each termination port of the plurality of termination ports being connected to the coupled transmission line at a different location to provide a plurality of coupling factors corresponding to a plurality of signal frequencies.

Abstract: In some embodiments, an amplifier system can include an amplifier circuit having first and second amplifiers configured to amplify respective first and second portions of an input signal. Each of the first and second amplifiers can include a cascode stage with input and output transistors arranged in a cascode configuration. The amplifier system can further include an envelope tracking bias circuit coupled to the amplifier circuit and configured to provide a bias signal to the output transistor of the cascode stage of at least one of the first and second amplifiers. The amplifier system can further include a supply circuit configured to provide a non-envelope tracking supply voltage to the output transistor of the cascode stage of the at least one of the first and second amplifiers.

Abstract: Apparatus and methods for power detection with enhanced dynamic range are provided. In certain embodiments, a front end system includes a power amplifier that amplifies a radio frequency (RF) input signal to generate an RF output signal, a directional coupler that generates a sensed RF signal based on sensing the RF output signal from the power amplifier, and a power detector that processes the sensed RF signal to generate a detection signal indicating an output power of the power amplifier. Additionally, the power detector includes two or more detection paths providing different amounts of gain to the sensed RF signal from the directional coupler.

Abstract: Devices and methods related to metallization of ceramic substrates for shielding applications. In some embodiments, a ceramic assembly includes a plurality of layers, the assembly including a boundary between a first region and a second region, the assembly further including a selected layer having a plurality of conductive features along the boundary, each conductive feature extending into the first region and the second region such that when the first region and the second region are separated to form their respective side walls, each side wall includes exposed portions of the conductive features capable of forming electrical connection with a conductive shielding layer.

Abstract: 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 circuit, a receiver that processes a receive signal from a second front end circuit, and a feedback receiver that processes a feedback signal from the first front end circuit to generate a digital interference cancellation signal that compensates the receiver for interference arising from the transmitter.

Abstract: A time error vector is determined using pairs of two closest points of input-referred noise data that straddle respective crossing times indicating when a clock signal representation crosses a threshold value, a slew rate of the clock signal representation, and the crossing times. A system filter is applied to the time error vector in the frequency domain. A first RMS value is determined indicating a jitter value present in the filtered time error vector. A raw clock signal time error vector of the clock signal under test is generated, the system filter is applied to the raw clock signal time error vector in the frequency domain, and a second RMS value indicating a jitter content of the filtered raw clock signal time error vector is determined. The second RMS value is corrected using the first RMS value to thereby generate a jitter measurement compensated for input-referred noise.

Abstract: Radio frequency front end modules are provided. In one aspect, a front end system includes at least one power amplifier configured to amplify a transmit radio frequency signal, at least one low noise amplifier configured to receive a receive radio frequency signal, an output node coupled to an antenna. The front end system also includes a first switch configured to selectively couple the output node to the at least one power amplifier during a transmit period and to the at least one low noise amplifier during a receive period, at least one transmit filter coupled between the power amplifier and the at least one switch, and at least one receive filter coupled between the low noise amplifier and the at least one switch. The front end system further includes a transmit supplemental filter, a receive supplemental filter, and a second switch.

Abstract: Antenna-plexers for interference cancellation are provided herein. In certain embodiments, a wireless device includes an antenna, an antenna-plexer coupled to the antenna and configured to generate a feedback signal, a transmitter configured to transmit a transmit signal to the antenna by way of the antenna-plexer, a receiver configured to process a receive signal, and a feedback receiver configured to process the feedback signal from the antenna-plexer to provide compensation to the receive signal.