Abstract: A filter includes a substrate; a signal line formed on the substrate and including an input terminal and an output terminal at either end of the signal line; and a first pair of resonant lines connected between the signal line and a ground portion, wherein the first pair of resonant lines are connected to the signal line at the same point.

Abstract: Radio frequency (RF) filter structures and related methods and RF front-end circuitry are disclosed. In one embodiment, an RF filter structure includes a first terminal and a first tunable RF filter path defined between the first terminal and a second terminal. The first tunable RF filter path is tunable to provide impedance matching between the first terminal and the second terminal at a first frequency. The first frequency may be provided within a first frequency band. Additionally, the RF filter structure includes a second tunable RF filter path defined between the first terminal and the second terminal. The second tunable RF filter path is tunable to provide impedance matching between the first terminal and the second terminal at a second frequency. The second frequency may be within a second frequency band. In this manner, the RF filter structure is configured to provide impedance tuning for multiple impedance bands simultaneously.

Abstract: An RF circuit includes a first dielectric material, a signal line and a bias line over a first surface of the first dielectric material, a conductive layer over a second surface of the first dielectric material, and a second dielectric material over the conductive layer. The first and second dielectric materials have different dielectric constants. The conductive layer includes a ground plane over which the signal line is formed. A conductive material void, with which a section of the bias line is aligned, is present in the second conductive layer. The RF circuit further includes a mounting area for an RF device. First ends of the signal line and the section of the bias line are located proximate to the mounting area to enable the signal line and the bias line to be electrically coupled with one or more leads of the RF device.

Abstract: RF communications circuitry, which includes a first RF filter structure, is disclosed. The first RF filter structure includes a first tunable RF filter path and a second tunable RF filter path. The first tunable RF filter path includes a pair of weakly coupled resonators. Additionally, a first filter parameter of the first tunable RF filter path is tuned based on a first filter control signal. A first filter parameter of the second tunable RF filter path is tuned based on a second filter control signal.

Abstract: An exemplary cavity resonator has a resonant frequency and includes a conductive body containing a cavity and a plate attached to the body enclosing the cavity. The position of a conductive tuning mechanism that protrudes into the cavity affects the tuning of the resonant frequency of the cavity resonator. A portion of the enclosed cavity is made of a shape memory alloy (SMA) material that has been trained to have a coefficient of thermal expansion that results in dimensional changes of the portion as the temperature varies so that the dimensional changes produce changes in the resonant frequency that counteract the combined change in the resonant frequency due to dimensional changes with temperature associated with the other portions of the enclosed cavity made of materials other than SMA material. This results in a stable resonant frequency versus temperature characteristic.

Abstract: Techniques to maintain gain flatness in the frequency response of a passband signal over a circuit chain. The techniques may be employed in the receive chain of a millimeter wave band wireless receiver, in the transmit chain of a millimeter wave band wireless transmitter, or in both the receive chain and the transmit chain of a millimeter wave band wireless transceiver. The techniques include mismatching the input and output impedance of a passive low pass filter used in the chain to peak the gain of the passband signal at or near the cutoff frequency (Fc) of the filter.

Abstract: A printed wiring board is provided with a wiring layer, a first ground layer, a second ground layer, a grounding through-hole, a signal through-hole, a first clearance, and a second clearance. The wiring layer has a signal line. The first ground layer has a first ground plane. The second ground layer is positioned between the wiring layer and the first ground layer and has a second ground plane. The grounding through-hole passes through the wiring layer, the first ground layer, and the second ground layer and is connected to the second ground plane. The signal through-hole passes through the wiring layer, the first ground layer, and the second ground layer and is connected to the signal line. The first clearance is formed in the first ground layer, is positioned in the vicinity of the signal through-hole and the grounding through-hole, and separates the first ground plane from the signal through-hole and the grounding through-hole.

Abstract: An electronic circuit includes at least two first conductors having line shapes which are arranged on a first plane of a substrate, a second conductor arranged on a second plane of the substrate, and a third conductor having a line shape, with at least part thereof being arranged on a third plane between the first plane and the second plane of the substrate. The open end of the third conductor is included in part of the third conductor which is arranged on the third plane, and the part is arranged to at least partly overlap one of at least the two first conductors and not to overlap the other first conductor when viewed from a direction perpendicular to the substrate.

Abstract: The present disclosure provides a switching power supply, an EMI filter, a common mode inductor and a wrapping method for the common mode inductor. The common mode inductor includes: a magnetic core; two multilayered coil windings symmetrically wrapped around the magnetic core; and two isolation gaps each of which is formed in respective one of the two multilayered coil windings, and is configured to divide, by beginning from a first layer, the respective one of the multilayered coil windings into two wrapping areas.

Abstract: A harmonics suppression filter includes a main circuit, a first inner circuit, a first outer circuit, a first inner node and a first outer node. The first inner circuit, the first outer circuit and the main circuit are in the same layer of the base board. Meanwhile, the first inner circuit is located inside of the main circuit. There is an inner gap between the first inner circuit and the main circuit. The first outer circuit is located outside of the main circuit. There is an outer gap between the first outer circuit and the main circuit. The first inner node is located in the inner gap to couple the first inner circuit with the main circuit. The first outer node is located in the outer gap to couple the first outer circuit with the main circuit.

Abstract: An inductor-capacitor (LC) filter designed to comply with EMC (Electromagnetic Compatibility) standards comprises capacitors; switches for coupling capacitors; differential-mode inductors for coupling capacitors and switches; and common-mode inductors or a combination of differential-mode inductors and common-mode inductors, where an input signal changes the inductance of differential-mode inductors in the LC filter to modify a frequency response of the LC filter. In the LC filter, differential-mode inductors further comprise identical multiple-winding inductors, and the input signal, which biases the plurality of differential-mode inductors, includes a DC signal or a combination of DC and AC signals. A corner-frequency of the LC filter is adjusted and approximated as: fc=1/(2×pi×sqrt(L×C)), where fc is the corner-frequency, L is a composite value of inductance, and C is a composite value of capacitance.

Abstract: Radio frequency (RF) front-end circuitry that includes control circuitry and an RF filter structure that includes a plurality of resonators are disclosed. In one embodiment, a first tunable RF filter path is defined by a first set of the plurality of resonators such that the first tunable RF filter path has a first amplitude and a first phase. A second tunable RF filter path is defined by a second set of the plurality of resonators such that the second tunable RF filter path has a second amplitude and a second phase. To provide antenna diversity and/or beam forming/beam steering, the control circuitry is configured to set a first amplitude difference between the first amplitude and the second amplitude to approximately a first target amplitude difference and set a first phase difference between the first phase and the second phase to approximately a first target phase difference.

Abstract: A noise filter includes a filter device and a filter retainer. The filter device includes a device unit having at least one capacitor provided therein, an input side lead wire extending from the device unit, an output side lead wire extending from the device unit, and a ground connection portion provided on the device unit. The filter device forms the noise filter that uses a mutual inductance between the input side lead wire and the output side lead wire. The filter retainer has a holding structure configured to maintain an arrangement of the input side lead wire and the output side lead wire. The arrangement forms an overlapping section in which the lead wires are closely opposed to each other. The noise filter may be attached to a harness.

Abstract: A transformer filter arrangement including a transformer having a first winding and a second winding is provided. Both of the first and the second windings are located between an outer border and an inner border, which is inside the outer border. The transformer filter arrangement further includes at least one reactive sub circuit, each including at least one inductor. The first winding of the transformer is divided into a plurality of winding segments. At least a first one of the at least one reactive sub circuit being connected in series with the winding segments of the first winding between two such winding segments, and having at least one of the at least one inductor located inside said inner border.

Abstract: RF duplexing and methods of operating the same are described herein. In one embodiment, an RF duplexing system may include a control circuit and a duplexer with a first tunable RF filter and second tunable RF filter. The control circuit is operable in a full duplexing transmission mode and a half duplexing transmission mode. The control circuit tunes the first tunable RF filter in the full duplexing transmission mode so that the first tunable RF filter defines a transmission passband and tune the second tunable RF filter so that the second tunable RF filter defines a receive passband. Also, the control circuit tunes one of the tunable RF filters so that the tunable RF filter defines the passband while the other tunable RF filter enhances the passband. In this manner, the tunable RF filters in the duplexer are both utilized to get better performance during the half duplexing mode.

Abstract: A radio frequency (RF) filter circuit for rejecting one or more spurious components of an input signal has a first resonator circuit including a first capacitor and a first coupled inductor pair of a first inductor and a second inductor, and a second resonator circuit with a second capacitor and a second coupled inductor pair of a third inductor and a fourth inductor. First and second resonator coupling capacitors are connected to the first resonator circuit and the second resonator circuit. A first port and a second port are connected to the first resonator circuit and the second resonator, with the filtered signal of the input signal passed through both the first resonator circuit and the second resonator circuit being output.

Abstract: A capacitance element body is configured by two or more capacitors, the capacitors being formed of a dielectric layer and at least three internal electrodes, the internal electrodes each being laminated via the dielectric layer and arranged to allow a center of gravity of an electrode body forming electrostatic capacitance to be arranged on a straight line in a lamination direction. In the capacitance element body, said two or more capacitors are serially connected in a lamination direction of the internal electrodes. Furthermore, external terminals, each being electrically connected to an electrode body forming electrostatic capacitance, are formed in side surfaces of the capacitance element body.

Abstract: A shell of an electronic device includes a base, two sidewalls, and a plurality of terminals. The base includes upper lateral and lower lateral surfaces opposite to each other. The two sidewalls are disposed at the upper lateral surface and are located separately at two opposite sides of the base. The two sidewalls are opposite to each other, with each sidewall having a surface that faces away from the base. The plurality of terminals is symmetrically arranged in order at the other opposite sides of the base and is embedded in the base. Each terminal includes an upper section and a lower section, with the upper section vertically extending upwards from the upper lateral surface, with the lower section horizontally extending outwards from the lower lateral surface, and with at least a portion of the lower section affixed flatly to the lower lateral surface.

Abstract: A coupler is presented that has high-directivity and low coupling coefficient variation. The coupler includes a first trace with a first edge substantially parallel to a second edge and substantially equal in length to the second edge. The first trace includes a third edge substantially parallel to a fourth edge. The fourth edge is divided into three segments. The outer segments are a first distance from the third edge. The middle segment is a second distance from the third edge. Further, the coupler includes a second trace, which includes a first edge substantially parallel to a second edge and substantially equal in length to the second edge. The second trace includes a third edge substantially parallel to a fourth edge. The fourth edge is divided into three segments. The outer segments are a first distance from the third edge. The middle segment is a second distance from the third edge.

Abstract: Embodiments of radio frequency (RF) front-end circuitry are disclosed where the RF front-end circuitry includes a tunable RF filter structure and a calibration circuit. The tunable RF filter structure includes (at least) a pair of weakly coupled resonators and defines a transfer function with a passband. The calibration circuit is configured to shape the passband so that the passband defines a center frequency. Additionally, the calibration circuit is configured to detect a phase difference at the target center frequency between the pair of weakly coupled resonators and adjust the phase difference of the pair of weakly coupled resonators at the target center frequency so as to reduce a frequency displacement between the center frequency of the passband and the target center frequency. In this manner, the calibration circuit calibrates the tunable RF filter structure to correct for errors in the center frequency of the passband due to component manufacturing variations.