61results about "Tunable filters" patented technology

An impedance matching network for a radio frequency (RF) transmission system can include first port for coupling to a first transistor differential pair. The network can further include a second port for coupling to a second transistor differential pair. The network can further include a matching network connected to the first port and the second port, the matching network comprised of a pair of coupled lines. Other aspects are described.

An embedded-cavity tunable filter integrated with high-quality, high-capacitance tuning ratio varactors, metal-insulator-metal (MIM) capacitors, and 3D inductors with alumina ceramic substrate through-vias is disclosed. The varactor and MIM capacitor dies are embedded in a blind alumina cavity (BAC) in an alumina ceramic substrate.

A switching circuit outputs a modulated signal. A low-pass filter circuit receives the modulated signal and applies low-pass filtering processing at a low-pass cut-off frequency to generate a demodulated signal to a load impedance. A replicating circuit receives the modulated signal and applies a replica of the low-pass filtering processing of the low-pass filter circuit to generate a reference signal. A signal processing circuit applies signal processing to the demodulated signal and the reference signal to generate at least one indicator signal which is indicative of a variation of the low-pass cut-off frequency.

A splitter / combiner having a first port, a second port, and a third port includes a first transmission line coupled between the first port and the second port, a second transmission line coupled between the first port and the third port, a resistor coupled between the second port and the third port, and first and second capacitors each having a first terminal and a second terminal, the first terminal of the first capacitor coupled to the second port, the first terminal of the second capacitor coupled to the third port, the second terminal of each of the first and second capacitors coupled to a common node. At least one of the first capacitor, second capacitor, first transmission line, and second transmission line is adjustable during operation for varying the electrical properties of the splitter / combiner.

An example filter for radio frequency signals in a radio includes first resonators (2021, 2022, 2023, 2024) coupled in series between an input (IN) and an output (OUT); a second resonator (2041, 2042, 2043, 2044) coupled as a shunt between a node in the series and a reference voltage; and a first circuit coupled in parallel with one of the first resonators or coupled in series with one of the second resonators, the first circuit including a switch (210, 404) coupled in series with an impedance (210, 410).

An active feedback RF resonator has a signal loop having a signal input and a signal output. The signal loop has a variable gain stage and at least one variable resonator, each variable resonator comprising an inductance element and a variable capacitance element comprising a number of switched fixed value capacitors and a variable capacitor. A phase noise of the active feedback RF signal has a maximum value for an operating frequency of the variable resonator that is based on an operating range of the variable capacitor.

A method for configuring a circuit for generating samples from a target distribution comprises: receiving a matrix representing parameters associated with the target distribution; tuning a plurality of tunable capacitance circuits in a tunable capacitance network based at least in part on respective elements of the matrix, wherein the tunable capacitance network consists essentially of interconnected wires intersecting at a plurality of nodes with selected pairs of nodes of the plurality of nodes interconnected by a respective tunable capacitance circuit of the plurality of tunable capacitance circuits and one or more nodes of the plurality of nodes connected to a common ground by a respective tunable capacitance circuit of the plurality of tunable capacitance circuits; recording respective voltage samples from the plurality of nodes of the tunable capacitance network; and storing a linear transformation of a vector of the voltage samples based at least in part on the matrix.

Resonator element for a filter, comprising the following: a first resonator comprising a first electrode (30) coupled to a first terminal, a second electrode (32) coupled to a second terminal, and a first piezoelectric material (31) arranged between the first electrode (30) and the second electrode (32), wherein the first terminal and the second terminal are configured for coupling to a filter structure, a second resonator with a third electrode (34) coupled to a third terminal, a fourth electrode (36) coupled to a fourth terminal, and a second piezoelectric material (35) arranged between the third electrode (34) and the fourth electrode (36), wherein the second resonator is acoustically coupled to the first resonator via at least one electrically insulating layer (33) between the second electrode (32) and the third electrode (34), and a tuning circuit (15) which is coupled to the third and fourth terminals.

Front-end systems with an adjustable filter architecture are provided. In certain embodiments, a front-end system includes a first bandpass filter with a first passband, a second bandpass filter with a second passband, a stopband filter with a stopband, and switches for controlling connectivity of the filters along transmit and receive paths. The first passband and the second passband include a frequency overlap region, which the stopband at least partially overlaps. The re-configurability of the switches allows for the overall filtering characteristic of the adjustable filter to adjust the duplex gap between transmit and receive passband edges, as well as the passband edges themselves.

The present invention relates to a design of a wireless power transmission system and a method for controlling an optimal resonance frequency applied to the system, and provides a wireless power transmission system and a method for controlling an optimal resonance frequency applied to the system, wherein, by a method of designing a power transmission unit to match a frequency control range and by designing a quality factor (Q) of a resonance unit of a power reception unit to be low so that the difference in power reception performance is not large within the control frequency range, power can be received stably even if there is a change in resonance frequencies of a wireless power transmission system installed in a metal environment, and the system frequency can be easily and quickly controlled so as to search for and find the optimal resonance frequency.

A power divider / combiner circuit may include a first port configured to receive a signal, a second port, and a third port. The circuit may include an unequal Wilkinson power divider / combiner circuit including a first node coupled to the first port, a second node coupled to the second port, and a third node. The unequal Wilkinson power divider / combiner circuit is configured to receive a signal at the first node and divide the signal to produce a first signal at the second node and a second signal at the third node. The circuit may include a configurable impedance transformation circuit coupled between the third node and the third port. The configurable impedance circuit is configured to provide a configurable phase shift and a configurable attenuation of the second signal to provide a selected power division ratio between the first signal at the second port and the second signal at the third port.

Multi-frequency capacitance cancellation in an acoustic filter circuit is provided. The acoustic filter circuit includes an acoustic resonator configured to resonate in a series resonance frequency to pass a radio frequency (RF) signal. However, the acoustic resonator may create an electrical capacitance that can cause the acoustic resonator to resonate at multiple operating frequencies outside the series resonance frequency, thus compromising performance of the acoustic resonator at these operating frequencies. Herein, a negative capacitance circuit is provided in parallel to the acoustic resonator and configured to present multiple negative capacitances to cancel (or at least reduce) the electrical capacitance at the operating frequencies. As a result, it is possible to improve the performance of the acoustic filter circuit across a broader frequency bandwidth.

A differential double balanced duplexer (dDBD) includes a transmitter and a first balun coupled to a first impedance tuner that produces a first impedance that blocks received signals at a first frequency range from travelling across the first balun and into the transmitter, and a second impedance that passes transmitted signals at a second frequency range to travel across the first balun to the antenna. The dDBD also includes a receiver and a second balun coupled to a second impedance tuner that produces a first impedance that allows the received signals at the first frequency range to travel across the second balun and into the receiver, and a second impedance that blocks the transmitted signals at the second frequency range from travelling across the second balun and into the receiver. As such, the dDBD allows for increased isolation and decreased insertion loss.

A phase shifting system, a chip, and a radar sensor are provided. A respective transmission line phase-shifting unit is configured to receive at least one phase shifting control signal and to shift a phase of a RF signal by a first phase or a second phase. Each transmission line phase-shifting unit includes a first group of transmission lines and a second group of transmission lines. At least some transmission lines in the first group of transmission lines of each transmission line phase-shifting unit are physically isolated from at least some transmission lines in the first group of transmission lines of an adjacent transmission line phase-shifting unit and transmission lines of the second group of transmission lines of each transmission line phase-shifting unit are coupled to respective transmission lines of the second group of transmission lines of an adjacent transmission line phase-shifting unit.

A wireless communication device includes at least two antennas and transmitter circuitry incorporating an attenuation circuit. The attenuation circuit has a first port coupled to a first power amplifier and a second port coupled to a second power amplifier. A matching network connects the first and second ports and comprises a pair of coupled lines. Auxiliary lines are coupled to the coupled lines to enable programmable attenuation while maintaining wideband performance. The coupled-line matching network provides compact, low-loss interstage impedance matching and supports integration into mmWave RF transmit chains. By leveraging auxiliary lines and associated attenuation control, the device achieves fine gain programmability with minimal insertion loss and negligible area overhead, improving linearity and efficiency relative to transformer-based designs. This architecture is suitable for high-frequency systems requiring robust gain control across large bandwidths, such as sub-THz and mmWave radios.

A notch filter is coupled to a first input node and a second input node, and is configured to present a capacitive load to a differential signal provided to the first and second input nodes, and to present a series-resonant inductive-capacitive load to a common-mode signal provided to the first and second input nodes. The notch filter includes a transformer and a capacitor bank. The transformer includes a first winding having a positive-polarity terminal coupled to the first input node and a second winding having a positive-polarity terminal coupled to the second input node. The capacitor bank includes a first capacitor coupled between a negative-polarity terminal of the first winding and a bias node, and a second capacitor coupled between a negative-polarity terminal of the second winding and the bias node. The first and second capacitors may be variable capacitors.

Disclosed is a calibration circuit, a calibration method for a filter and a filter device. The calibration circuit includes: a signal receiving terminal, receiving an output signal from the filter; a frequency detection module, obtaining a count value according to the output signal, the count value representing a frequency of the output signal; an adjustment module, adjusting the control signal according to the count value and a target value representing a target frequency, to adjust the frequency of the output signal provided by the filter until a calibration value, which allows the count value to be consistent with the target value, of the control signal is determined. The filter performs filtering according to the control signal with the calibration value in an operating stage. The calibration circuit performs feedback adjustment on the filter to achieve bandwidth calibration with high calibration accuracy and simple circuit structure.

According to an aspect, there is provided a tunable radio frequency filter (209) for preselection in a multiband radio receiver or transceiver with a low-noise amplifier with a single-ended input. The tunable radio frequency filter comprises a first capacitor (C1, 1001) having a first terminal for connecting to at least one antenna of the multiband radio receiver or transceiver and a second terminal; and a series resonant circuit, connected between the second terminal of the first capacitor and the ground. The series resonant circuit comprises a first inductor (L1 1003) and a tunable capacitor (Ct, 1004) connected in series with first inductor and having a plurality of tuning values corresponding to operating frequency bands of the multiband radio receiver or transceiver. The tunable capacitor is implemented in an integrated circuit. The series resonant circuit is configured to be resonant at a plurality of first subharmonics of frequencies of the operating frequency bands. Optionally the filter comprises a second capacitor (C2, 1002) and a second inductor (L2, 1010) in series between the resonant circuit to ground and the input of the LNA. The second inductor adds to impedance matching and low pass filtering above the operating frequency bands.

An example filter for radio frequency (RF) signals in a radio includes first resonators coupled in series between an input and an output; a second resonator coupled as a shunt between a node in the series and a reference voltage; and a first circuit coupled in parallel with one of the first resonators, the first circuit including a switch coupled in series with an impedance.

Embodiments of this application relate to the field of communication technologies and provide a radio frequency transmission circuit and an electronic device, so that a direct current signal can be introduced into a radio frequency line in a simple manner to meet a large radio frequency bandwidth, and costs are low. The radio frequency transmission circuit includes: a first radio frequency input end and a direct current blocking capacitor, where a first end of the direct current blocking capacitor is electrically connected to the first radio frequency input end; a first LC filter, where an input end of the first LC filter is electrically connected to a second end of the direct current blocking capacitor, an output end of the first LC filter is electrically connected to an output end of the radio frequency transmission circuit, and the first LC filter is a low-pass filter; and a direct current input end and a ferrite bead, where the direct current input end is electrically connected to the input end of the first LC filter or between two inductors of the first LC filter through the ferrite bead.

An electronic device may include a wireless circuit having a first circuit, a second circuit, and an impedance matching network coupled between the first circuit and the second circuit. The impedance matching network may include a transformer having a primary coil and a secondary coil and a first feed-forward resistor having a first terminal coupled to the primary coil and having a second terminal coupled to the secondary coil. The impedance matching network may also include a second feed-forward resistor coupled between the primary coil and the secondary coil. The first feed-forward resistor and the second feed-forward resistor may be configured to provide a flat passband gain response for the impedance matching network.

A millimeter-wave low-pass / high-pass reconfigurable filter comprising a series-parallel reconfiguration structure, a passband compensation inductor, and a ground-direct connection reconfiguration structure is disclosed. It enables the interchange of filter passband and stopband in two modes, achieving reconfigurable output in both high-frequency and low-frequency bands, along with low loss in the passband and effective image signal rejection in the stopband, thereby realizing hardware reuse. The circuit structure of the millimeter-wave low-pass / high-pass reconfigurable filter according to the invention is compact and well-suited for use in multi-band millimeter-wave reconfigurable transceivers.

This application relates to an impedance matching array, a matching method, a radio frequency power supply, and a plasma radio frequency system that solve the problem of impedance matching. The impedance matching array includes a plurality of reactance assemblies connected in parallel in stages between the input and output sides. Each stage of the reactance assembly includes a reactance unit, an input transistor, an output transistor, and a series-connected transistor. The input transistor of a given stage is connected between the input side of the impedance matching array and the input side of the reactance unit of the given stage. The output transistor of a given stage is connected between the output side of the reactance unit of the given stage and the output side of the impedance matching array. The series-connected transistor of a given stage is connected between the output side of the reactance unit of the given stage and the input side of the reactance unit of the next stage. By controlling the on / off states of the input transistors, output transistors, and series-connected transistors in each stage of the reactance assembly, a reactance combination is formed to achieve impedance matching. This application enables rapid impedance matching by switching each of the on / off transistors in the reactance assembly.

A reflection-type phase shifter device (RTPS) includes at least two reflective loads having values (for example, capacitance values) that can be set independently of one another.

A system for filter enhancement, preferably including one or more analog taps and a controller, and optionally including one or more couplers. The system is preferably configured to integrate with a filter, such as a passband filter or other frequency-based filter. The system can be configured to integrate with an RF communication system, an RF front end, or any other suitable RF circuitry. A method for filter enhancement, preferably including configuring one or more analog taps, and optionally including calibrating a system for filter enhancement and / or receiving temperature information.

A power divider / combiner circuit may include a first port configured to receive a signal, a second port, and a third port. The circuit may include an unequal Wilkinson power divider / combiner circuit including a first node coupled to the first port, a second node coupled to the second port, and a third node. The unequal Wilkinson power divider / combiner circuit is configured to receive a signal at the first node and divide the signal to produce a first signal at the second node and a second signal at the third node. The circuit may include a configurable impedance transformation circuit coupled between the third node and the third port. The configurable impedance circuit is configured to provide a configurable phase shift and a configurable attenuation of the second signal to provide a selected power division ratio between the first signal at the second port and the second signal at the third port.

In accordance with a first aspect of the present disclosure, an active RC-type filter is provided, comprising: an input, an output and a signal path between said input and output; at least one capacitor bank and at least one resistor bank, wherein said capacitor bank and resistor bank are integrated into the signal path; wherein the resistor bank comprises a plurality of resistor ladders; wherein each one of said resistor ladders comprises a plurality of resistors connected in series; wherein each one of said resistors has an input node configured to be coupled selectively to the signal path through one of a plurality of controllable switches; and wherein said resistor ladders have output nodes directly coupled to each other and to the signal path. In accordance with a second aspect of the present disclosure, a corresponding method of implementing an active RC-type filter is conceived.

A stacked resonator circuit that includes a transformer and multiple resonator circuits is disclosed. The transformer circuit may include a primary coil and secondary coil and may receive an input signal from a particular circuit. The multiple resonator circuit, which are coupled to the transformer, may attenuate one or more frequency components included in the input signal to generate a filtered version of the input signal. The transformer circuit can relay the filtered version of the input signal to a different circuit.

A wireless circuit is provided that includes an antenna and an impedance matching circuit coupled to the antenna. The impedance matching circuit may include a primary coil, a first secondary coil magnetically coupled to the primary coil at a first coupling amount, and a second secondary coil magnetically coupled to the primary coil at a second coupling amount different from the first coupling amount. The impedance matching circuit may also include a capacitor having a first terminal coupled to a node disposed between the first secondary coil and the second secondary coil, and having a second terminal coupled to a ground power line. The capacitor may be configured as a harmonic suppression component for filtering spurious harmonic signals.

An adjustable inductor includes an annular magnetic core defining a plurality of gaps, a compressible gap material positioned in the gaps, at least one winding wound on the magnetic core, a force applying structure, and a film substantially covering the adjustable inductor. The force applying structure is operable to apply a force to the magnetic core to adjust the gaps, and thereby adjust an inductance of the adjustable inductor. The film is configured to prevent movement of the force applying structure when above a predetermined temperature threshold, and to allow movement of the force applying structure when below the predetermined threshold.