Abstract: Apparatus and methods for radio frequency emissions testing based on harmonic beamforming are provided herein. In certain configurations, a method of emissions testing of cellular communication assemblies for emissions compliance is provided. The method includes transmitting a signal beam using an antenna array of a respective cellular communication assembly after manufacture thereof, the signal beam including a fundamental lobe and one or more harmonic lobes. The method further includes determining one or more testing locations of the signal beam based on detecting a direction of the fundamental lobe using test equipment, the testing locations corresponding to locations associated with the harmonic lobes. The method further includes evaluating a level of harmonic emissions at each of the one or more testing locations using the test equipment to establish whether or not the respective cellular communication assembly complies with emissions testing.

Abstract: In some embodiments, an attenuator can include a first group of attenuation steps with each attenuation step being configured to switchably provide a first attenuation value, and a second group of attenuation steps with each attenuation step being configured to switchably provide a second attenuation value less than the first attenuation value. The attenuator can be capable of providing a total attenuation value from approximately zero to a sum of the attenuation steps of the first group and the second group in increments of the second attenuation value. With such a configuration, a glitch can have a maximum magnitude that is a difference between the first attenuation value and the second attenuation value during a change in the total attenuation value.

Abstract: Diversity receiver front end system with variable-gain amplifiers. A receiving system can include a controller configured to selectively activate one or more of a plurality of paths between an input of a first multiplexer and an output of a second multiplexer. The receiving system can further include a plurality of bandpass filters, each one of the plurality of bandpass filters disposed along a corresponding one of the plurality of paths and configured to filter a signal received at the bandpass filter to a respective frequency band. The receiving system can further include a plurality of variable-gain amplifiers (VGAs), each one of the plurality of VGAs disposed along a corresponding one of the plurality of paths and configured to amplify a signal received at the VGA with a gain controlled by an amplifier control signal received from the controller.

Abstract: Carrier aggregation systems and methods are disclosed. In some embodiments, a radio-frequency circuit can include a first signal path configured to present an approximately zero impedance to a first out-of-band signal that is out of a first frequency band. The radio-frequency circuit can further include a coupling circuit coupled to the first signal path and configured such that the approximately zero impedance presented by the first signal path to the first out-of-band signal results in the first out-of-band signal being substantially excluded from the first signal path. The radio-frequency circuit can further include a second signal path configured to present an approximately zero impedance to a second out-of-band signal that is out of a second frequency band.

Abstract: Apparatus and methods related to beamforming of harmonics are provided herein. In certain implementations, a communication device for operating in a wireless network is provided. The communication device includes an antenna array including a plurality of antenna elements that generate a plurality of receive signals in response to a radio wave, a plurality of signal conditioning circuits operatively associated with the plurality of antenna elements and that condition the plurality of receive signals to provide beamforming of a receive beam, and a beam control circuit that controls the plurality of signal conditioning circuits to provide beam steering of the receive beam based on a direction of one or more harmonic lobes of the receive beam.

Abstract: Apparatus and methods for radio frequency emissions testing based on harmonic beamforming are provided herein. In certain configurations, a method of emissions testing of cellular communication assemblies for emissions compliance is provided. The method includes transmitting a signal beam using an antenna array of a respective cellular communication assembly after manufacture thereof, the signal beam including a fundamental lobe and one or more harmonic lobes. The method further includes determining one or more testing locations of the signal beam based on detecting a direction of the fundamental lobe using test equipment, the testing locations corresponding to locations associated with the harmonic lobes. The method further includes evaluating a level of harmonic emissions at each of the one or more testing locations using the test equipment to establish whether or not the respective cellular communication assembly complies with emissions testing.

Abstract: Systems and methods for suppressing transient outputs from an amplifier system are provided. An amplifier having a plurality of bias levels may be controlled to initiate a change in the level of a bias signal provided to the amplifier. The level of the bias signal is ramped from an initial bias level to a final bias level over numerous steps. The steps include at least one step in which the level of the bias signal is between the initial bias level and the final bias level. An amplifier system having multiple stages may be controlled to enable each stage and selectively couple each stage in a sequence that couples an output stage to an output terminal at the completion of the sequence.

Abstract: Amplifier systems and methods are provided that include a fixed gain amplification stage coupled to an adjustable attenuation stage further coupled to a variable gain amplification stage. A controller controls an amount of attenuation provided by the adjustable attenuation stage and an amount of gain provided by the variable gain amplification stage to maintain any of various noise, efficiency, and/or linearity requirements of the amplifier system.

Abstract: Systems and methods are provided for reducing the effects of an impedance mismatch between a communications system and a shared communications medium. A communication system, such as a transceiver within a cable modem, switches between various operating modes including a transmit mode, a receive mode, and a standby mode. The standby mode may be used while the transceiver is in an idle state between modes, such as while changing an amplifier gain states in between transmissions. While transitioning between modes, the impedance presented by the communications system can temporarily fluctuate causing unwanted signal reflections to propagate out of the communications system and on to the shared medium. Circuitry within the communications system, such as transmission circuitry including an adjustable attenuator, may be placed into a hybrid attenuation-isolation mode during the transition causing the magnitude of any unwanted signal reflections to be attenuated and reducing the impact on the shared medium.

Abstract: Diversity receiver front end system with variable-gain amplifiers. A receiving system can include a controller configured to selectively activate one or more of a plurality of paths between an input of a first multiplexer and an output of a second multiplexer. The receiving system can further include a plurality of bandpass filters, each one of the plurality of bandpass filters disposed along a corresponding one of the plurality of paths and configured to filter a signal received at the bandpass filter to a respective frequency band. The receiving system can further include a plurality of variable-gain amplifiers (VGAs), each one of the plurality of VGAs disposed along a corresponding one of the plurality of paths and configured to amplify a signal received at the VGA with a gain controlled by an amplifier control signal received from the controller.

Abstract: Systems, devices and methods related to diversity receivers. In some embodiments, a receiving system can include a controller configured to selectively activate one or more of a plurality of paths between an input and an output, and a plurality of amplifiers, with each one of the plurality of amplifiers disposed along a corresponding one of the plurality of paths and configured to amplify a signal received at the amplifier. The receiving system can further include two or more of features including (a) variable-gain amplifiers, (b) phase-shifting components, (c) impedance matching components, (d) post-amplifier filters, (e) a switching network, and (f) flexible band routing. In some embodiments, such a receiving system can be implemented as a diversity receive (DRx) module.

Abstract: A wireless communication device includes a radio frequency antenna a transceiver. The transceiver includes a receiver having a switching architecture configured to generate a plurality of output phases within a local oscillator period based on the filtered RF signal and a respective plurality of local oscillator signals. The plurality of output phases can be organized into at least K groups where K is an integer of four or greater, and each nth group of the K groups includes nth and (n+K)th output phases of the plurality of output phases. The receiver can difference the nth and (n+K)th output phases of each respective group of the K groups, resulting in gain-added output phases.

Abstract: Diversity receiver front end system with flexible band routing. A receiving system can include a plurality of amplifiers, each one of the plurality of amplifiers disposed along a corresponding one of a plurality of paths between an input of the receiving system and an output of the receiving system and configured to amplify a radio-frequency (RF) signal received at the amplifier. The receiving system can further include an input multiplexer configured to receive one or more RF signals at one or more input multiplexer inputs and to output each of the one or more RF signals to one or more of a plurality of input multiplexer outputs to propagate along a respective one or more of the plurality of paths.

Abstract: Described herein are radio-frequency (RF) modules that include shielding for improved RF performance. The RF modules including a packaging substrate with a receiving system implemented thereon. The RF module includes a shield implemented to provide RF shielding for at least a portion of the receiving system. The receiving system can include any combination of pre-amplifier or post-amplifier bandpass filters, amplifiers, switching networks, impedance matching components, phase-shifting components, input multiplexers, and output multiplexers. The shielding can include a conductive layer within a conformal shielding on an upper side and side walls of the RF module. The shielding can be an overmold formed over the packaging substrate. The conductive layer can be connected to one or more ground planes. The packaging substrate can include contact features on an underside of the substrate for mounting an underside component.

Abstract: Diversity receiver front end system with flexible antenna routing. A receiving system can include a plurality of amplifiers. Each one of the plurality of amplifiers can be disposed along a corresponding one of a plurality of paths between an input of the receiving system and an output of the receiving system. Each one of the plurality of paths can correspond to a different frequency band. The receiving system can include an input multiplexer configured to receive, at one or more of a plurality of input multiplexer inputs, one or more RF signals. Each one of the one or more RF signals can include one or more frequency bands. The input multiplexer can be configured to output each of the one or more RF signals to one or more of a plurality of input multiplexer outputs.

Abstract: An ‘L’ shaped dynamically configurable impedance matching circuit is presented herein. The circuit can include a series element and a shunt element. The shunt element in the L-shaped impedance matching circuit can be moved or modified based on the impedance of the circuit elements in electrical communication with each side of the impedance matching circuit. Thus, in some cases, the impedance matching circuit may be a flexible circuit that can be dynamically modified based on the environment or configuration of the wireless device that includes the impedance matching circuit.

Abstract: An ‘L’ shaped dynamically configurable impedance matching circuit is presented herein. The circuit can include a series element and a shunt element. The shunt element in the L-shaped impedance matching circuit can be moved or modified based on the impedance of the circuit elements in electrical communication with each side of the impedance matching circuit. Thus, in some cases, the impedance matching circuit may be a flexible circuit that can be dynamically modified based on the environment or configuration of the wireless device that includes the impedance matching circuit.

Abstract: Carrier aggregation systems and methods are disclosed. In some embodiments, a radio-frequency circuit can include a first signal path configured to present an approximately zero impedance to a first out-of-band signal that is out of a first frequency band. The radio-frequency circuit can further include a coupling circuit coupled to the first signal path and configured such that the approximately zero impedance presented by the first signal path to the first out-of-band signal results in the first out-of-band signal being substantially excluded from the first signal path. The radio-frequency circuit can further include a second signal path configured to present an approximately zero impedance to a second out-of-band signal that is out of a second frequency band.

Abstract: A low noise receiver includes a downconverter configured to receive a radio frequency (RF) signal, the downconverter comprising a switching architecture configured to generate a plurality of output phases based on a respective plurality of local oscillator (LO) signals, a differencing circuit configured to combine the plurality of output phases such that an nth output phase is differenced with an (n+K)th output phase, resulting in gain-added output phases, and a summation filter configured to receive the gain-added output phases and configured to combine the gain-added output phases such that a response of the receiver effectively reduces odd harmonics of the RF signal.

Abstract: An ‘L’ shaped dynamically configurable impedance matching circuit is presented herein. The circuit can include a series element and a shunt element. The shunt element in the L-shaped impedance matching circuit can be moved or modified based on the impedance of the circuit elements in electrical communication with each side of the impedance matching circuit. Thus, in some cases, the impedance matching circuit may be a flexible circuit that can be dynamically modified based on the environment or configuration of the wireless device that includes the impedance matching circuit.