A wireless communication device is described. The wireless communication device includes a processor, a memory in communication with the processor and instructions stored in the memory. The instructions are executable by the processor to detect a signal degradation indication for a radio frequency (RF) signal. The instructions are also executable by the processor to cause a switch to select a combination of a first matching network and a second matching network coupled to an antenna in response to detecting the signal degradation indication.

A multiplexer (10) includes a common terminal (100c), a filter (21) that supports Band 41, a filter (22) that supports Band 40, and a filter (23) that supports Band 1Rx. A matching circuit (11) includes a capacitor (C1) connected in a path (111), a switch (SW1) connected between a ground and a node in the path (111) between the capacitor (C1) and the filter (21), a resonant circuit connected in a path (112) and having a resonant frequency in Band 40, the resonant frequency being a frequency at which an impedance is minimum, a switch (SW2) connected between the ground and a node in the path (112) between the resonant circuit and the filter (22), an inductor (L1) connected in a path (113), and a switch (SW3) connected between the ground and a node in the path (113) between the inductor (L1) and the filter (23).

According to one embodiment, an IC chip includes a plurality of fuse elements including a plurality of fuse portions each of which is to be cut off by a stress, and a plurality of actuator portions provided for the plurality of fuse portions, respectively, and each of which applies a stress to corresponding one of fuse portions, and a control circuit supplying a control signal for cutting off desired one of the fuse portions to corresponding one of the actuator portions.

The present technology is directed to a system and method for implementing passive power harvesting from ambient electromagnetic emissions with a smart rectenna that incorporates automatic frequency response tuning features. The disclosed system incorporates a tunable High Pass Filter and voltage multiplier rectifier with a front-end ultra wide band antenna unit. The frequency response of tunable components can be actively adjusted to match the frequency band containing most of the energy in the incident electromagnetic emission. A look up table is used for determining the appropriate biasing levels of the tunable components for each frequency in a frequency band of interest. By tuning a frequency response of impedance matching, filtering and rectifying components to correspond to a frequency region of maximum power spectral density in the incident energy signal, the system facilitates the scavenging of ambient electromagnetic energy from the spectral region with the highest power spectral density.

An RF front end provides high receive selectivity by selectively configuring matching networks within a Time Division Duplex transceiver. One or more elements of the transmit or receive signal paths are configured to perform multiple functions. Each of the functions can be performed in dependence on an operating mode of the RF front end. In some embodiments, one or more elements in the transmit or receive signal paths are reconfigured during receive portions of operation to provide additional receive selectivity.

A filter module (20) includes a filter circuit (22) that includes switches (221SW and 224SW), a pass band of the filter circuit (22) being switched in accordance with switching between ON and OFF of the switches (221SW and 224SW); and an impedance matching circuit (21) that is disposed in at least one of a preceding stage and a subsequent stage of the filter circuit (22) and that includes a switch (212SW), an element value for achieving impedance matching being switched in the impedance matching circuit (21) in accordance with switching between ON and OFF of the switch (212SW). The switches (221SW and 224SW) and the switch (212SW) synchronize with each other regarding timing of switching between ON and OFF.

A method of constructing an amplifier circuit includes simulating an output of an amplifier device of the amplifier circuit over a range of impedances to yield a simulated maximum power and a simulated maximum power added efficiency at a particular frequency, fabricating a plurality of output matching networks and input matching networks with impedances above and below the impedances that yield the simulated maximum power and simulated maximum power added efficiency, empirically determining physical dimensions of an optimized output matching network and an optimized input matching network that result in actual impedances that provide an actual maximum power and maximum power added efficiency at the particular frequency, and coupling the optimized output matching network to an output of the amplifier device and coupling the optimized input matching network between an output of a driver circuit and an input of the amplifier device.

A radio frequency front-end circuit performs, in a communication band made up of a plurality of communication channels within a particular frequency band used in a system, wireless communication through a use channel selected from among empty communication channels in the plurality of communication channels, the radio frequency front-end circuit including a transmission-side amplifier circuit and a transmission circuit both serving as a transmission-side circuit that produces, from a transmitted signal after being subjected to a predistortion process, a transmitted signal corresponding to the use channel, and a frequency variable filter serving as a tunable filter that attenuates a radio frequency signal of a spurious wave at least in an alternate adjacent channel relative to the use channel.

A radio-frequency module includes a multilayer substrate, an input switch, an output switch, and filters. A switch IC is disposed on a main surface of the multilayer substrate. The input switch is disposed in the switch IC and includes a first input terminal and first output terminals. The output switch is disposed in the switch IC and includes second input terminals and a second output terminal. The filters are disposed outside the switch IC and are connected to the first output terminals and the second input terminals. In a plan view of the multilayer substrate, the first input terminal and the first output terminals are disposed close to a first side of an exterior of the switch IC, and the second input terminals and the second output terminal are disposed close to a second side different from the first side of the exterior of the switch IC.

The present disclosure relates to a front-end module for a telecommunication device with an EBD circuit comprising a hybrid transformer for coupling via a transmit port to the telecommunication device transmitting a first frequency transmit signal, to an antenna, via a receive port to the telecommunication device receiving a second frequency receive signal, and to a tunable impedance circuit. In a first configuration the EBD circuit is configured to isolate the transmit port from the receive port at the first frequency, and the FEM comprises a first filter at the transmit port for attenuating the transmit signal with a predetermined amount at the second frequency. In a second configuration the EBD circuit is configured to isolate the transmit port from the receive port at the second frequency, and the FEM comprises a second filter at the receive port for attenuating the receive signal a predetermined amount at the first frequency.