Abstract:
Radio frequency (RF) systems with tunable filters are provided herein. In certain embodiments, an RF system includes a first RF processing circuit configured to process a first frequency band of a first communication standard and a second frequency band of a second communication standard. The first frequency band and the second frequency band are close in frequency and/or partially overlapping in frequency. The first RF processing circuit includes a tunable filter for changing the bandwidth of the first RF processing circuit to enhance the robustness of the first RF processing circuit to blocker or jammer signals of a third frequency band.
Abstract:
Radio frequency front end modules implementing coexisting time division duplexing and frequency division duplexing are provided. In one aspect, a front end system includes a time-division duplexing transmit terminal, a time-division duplexing receive terminal, a frequency division duplexing terminal, and an antenna terminal. The front end system further includes first, second, and third switches configured to selectively connect the terminals to either a node or the antenna. The front end system also includes a controller configured to provide delays between disconnecting the terminals from the antenna and connecting the terminals to the node.
Abstract:
Described herein are systems configured for carrier aggregation. Systems include a multiplexing circuit having a filter assembly, switching circuit with a switching path, and a switchable impedance. The filters can be designed so that when operated simultaneously (e.g., during multi-band operation) the same inductance can be used allowing the switching network to switch in a particular inductance into the path. The described systems can include an inductance that is coupled to an output port so that when operating in single-band mode, the different paths share the same inductance. Relative to other solutions, the described systems can improve performance (e.g., reduce insertion loss), reduce the number of components in the associated module, reduce manufacturing costs, and the like.
Abstract:
A front-end module (FEM) is disclosed that includes an integrous signal combiner. The integrous signal combiner can process received signals and use a set of resonant circuits to filter signal noise prior to recombination of a plurality of signal bands that form an aggregate carrier signal. These resonant circuits may be placed after a set of low noise amplifiers and can be used to more efficiently reduce noise and parasitic loading within each of a set of signal paths. Each resonant circuit may be configured to filter noise relating to a bandwidth for a signal that is to be combined with the signal of the signal path that includes the resonant circuit. In some implementations, the integrous signal combiner can be a tunable integrous signal combiner with resonant circuits that may be reconfigurable or dynamically configurable.
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:
Diversity modules for processing radio frequency (RF) signals are provided herein. In certain implementations a diversity module includes a first terminal, a second terminal, a low band processing circuit that generates a low band signal based on one or more diversity signals, a mid band processing circuit that generates a mid band signal based on the one or more diversity signals and that provides the mid band signal to the second terminal, a high band processing circuit that generates a high band signal based on the one or more diversity signals, and a multi-throw switch that provides the low band signal to the first terminal in a first state and that provides the high band signal to the first terminal in a second state.
Abstract:
Diversity receiver front end system with post-amplifier filters. 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 amplifiers. Each one of the plurality of amplifiers can be disposed along a corresponding one of the plurality of paths and can be configured to amplify a signal received at the amplifier. The receiving system can include a first plurality of bandpass filters. Each one of the first plurality of bandpass filters can be disposed along a corresponding one of the plurality of paths at an output of a corresponding one of the plurality of amplifiers and can be configured to filter a signal received at the bandpass filter to a respective frequency band.
Abstract:
Diversity receiver front end system with impedance matching components. A receiving system can include a controller configured to selectively activate one or more of a plurality of paths between an input of the receiving system and an output of the receiving system. The receiving system can further include a plurality of amplifiers. Each one of the plurality of amplifiers can be disposed along a corresponding one of the plurality of paths and can be configured to amplify a signal received at the amplifier. The receiving system can further include a plurality of impedance matching components. Each one of the plurality of impedance matching components can be disposed along a corresponding one of the plurality of paths and can be configured to reduce at least one of an out-of-band noise figure or an out-of-band gain of the one of the plurality of paths.
Abstract:
Diversity receiver front end system with phase-shifting components. A receiving system can include a controller configured to selectively activate one or more of a plurality of paths between an input of the receiving system and an output of the receiving system. The receiving system can further include a plurality of amplifiers, 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 a plurality of phase-shift components, each one of the plurality of phase-shift components disposed along a corresponding one of the plurality of paths and configured to phase-shift a signal passing through the phase-shift component.
Abstract:
Disclosed are systems, devices and methods related to mixed mode time interleaved digital-to-analog converters (DACs). In some embodiments, such DACs can be utilized for radio-frequency (RF) applications. In some embodiments, a DAC for RF applications can include a first circuit configured to receive a digital signal and perform a first operation to yield an increased bandwidth of the DAC. The DAC can further include a second circuit configured to perform a second operation on the digital signal to yield an analog signal representative of the digital signal. The second circuit can be further configured to reduce or remove an image within the increased bandwidth.