Abstract: A filter circuit topology for filtering a radio frequency input signal includes one or more inductor devices, such as, for example, discrete chip or air coils. The inductor devices are center tapped into a capacitor coupled to the ground. The center-tapped inductor configuration splits the output voltage across the inductor devices into two equal voltages of predetermined amplitude determined by the quality factor of the filter circuit. The filter circuit further includes an input capacitor to receive the RF input signal and an output capacitor coupled respectively to the inductor devices, the output capacitor having a variable capacitance, the inductor devices and the variable capacitor forming an inductive-capacitive (LC) filter capable of filtering the RF input signal and generating an output filtered signal for further transmission to a television tuner.

Abstract: A compact bandpass filter within a multilayered low temperature co-fired ceramic (LTCC) substrate is provided. Each resonator comprises an inductor and a capacitor connected in parallel. A top ceramic substrate comprises a top conductive plate to form a first RF ground plane. A bottom ceramic substrate comprises a bottom conductive plate to form a second RF ground plane. A first ceramic substrate is between the top and bottom ceramic substrates. All inductors of the resonators are serpentine conductive traces on the first ceramic substrate. A second ceramic substrate is between the first and bottom ceramic substrates, having a plurality of conductive plates to form a plurality of capacitors that transmit RF signal from an input node of the bandpass filter to an output node of the bandpass filter. The resonators are located between the too and bottom conductive plates.

Abstract: Dielectrics fixed on holders respectively provided at semi-coaxial cavity resonator stages are movably inserted through an outer conductor. The holders projecting out of the outer conductor are coupled to a coupling member, and the coupling member is directed to slide or turn, so that distances between the dielectrics and the inner conductors of the resonators are varied, and accordingly frequencies of the resonators are varied at the same time. Accordingly, there is provided a tunable filter that avoids an increase in insertion loss, is high-power resistant, does not cause intermodulation, and allows a center frequency of the filter to be varied steplessly and quickly.

Abstract: The present invention provides an RF module capable of converting electromagnetic waves in the TE mode to balanced electromagnetic waves in the TEM mode without adjustment and outputting the balanced electromagnetic waves while easily realizing miniaturization. The RF module includes: a waveguide (3) in which a half-wavelength TE mode resonator (2) is formed; an E plane coupling window (4) formed in a wall portion (3a) orthogonal to an H plane out of wall portions (3a) to (3e) constructing the TE mode resonator (2) in the waveguide (3); an output line (5a) provided at the edge on the side of the wall portion (3d) parallel with the H plane on the E plane coupling window (4), and magnetically coupled to electromagnetic waves in the TE mode resonator (2); and another output line (5b) provided at the edge on the side of the wall portion (3e) parallel with the H plane in the E plane coupling window (4), and magnetically coupled to the electromagnetic waves.

Abstract: A parallel coupled line filter is miniaturized by using lumped capacitors and grounding the capacitors. The parallel coupled line filter includes a parallel coupled line, a first capacitor connected to one of two input ports of the parallel coupled line, and a second capacitor connected to one of two output ports of the parallel coupled line. The parallel coupled filter can be miniaturized to a desirable size, on the basis of relatively simple theoretical knowledge. The parallel coupled line filter exhibits excellent frequency selectivity and improved harmonic characteristics.

Abstract: An undesired-wave propagation blocking circuit that blocks an undesired wave propagating between at least two parallel planar conductors is formed by a band eliminate filter including a plurality of stages of resonators and transmission lines each connecting the resonators in the respective stages. Each of the resonators in the respective stages has two spiral lines that extend in parallel to each other from each root portion, and leading ends of the spiral lines are connected to each other. Each root portion of the two spiral lines of the resonators is connected to a plurality of positions of the two transmission lines, and each of the resonators is short-circuited at one of respective short-circuit portions, which is a root portion.

Abstract: Four input nodes I1-I4 for inputting 4-phase signals, four resistors R1-R4, four capacitors C1-C4, and four output nodes O1-O4 for outputting 4-phase signals are provided. The resistors and the capacitors are connected alternately in a loop, and the input nodes and output nodes are connected alternately to the respective nodes between the resistors and the capacitors sequentially. Each of the four resistors is composed of a group of three or more partial resistors, and three groups of the partial resistors R2a-R2c, R3a-R3c and R4a-R4c are collected respectively and arranged in the same attitude, while the partial resistors R1a-R1c of the remaining group are distributed into the other groups and arranged in the same line the same attitude as the partial resistors of each of the other groups. The regions of the thus collected groups are arranged in one direction.

Abstract: A surface acoustic wave (SAW) device includes at least an IC region and a SAW element region. A semiconductor element layer and wiring layer is located in the IC region, and the semiconductor element layer has a semiconductor element and an element insulating film. The wiring layer is formed by stacking wiring to connect with the semiconductor element and a wiring insulating film extending to the SAW region. The semiconductor element layer further includes a piezoelectric thin film formed above the wiring insulating film, and in the SAW element region, a SAW element is formed on the piezoelectric thin film equipped with an IDT electrode provided with a plurality of electrode fingers, and at least one layer of layer thickness adjusting films having linear shapes and arranged in parallel to and with the same pitch as the electrode fingers of the IDT electrode.

Abstract: In a semi-coaxial cavity resonator in which an inner conductor is fixed to an outer conductor with a screw, an inner cavity where the inner conductor does not engage with the screw is provided to extend from a bearing surface of the inner conductor to a region of an internal thread hole formed inside the inner conductor which does engage with the screw, thereby providing a region where the screw is deformable. Accordingly, deviation in perpendicularity of the screw relative to the bearing surface, deviation in perpendicularity of the internal thread hole of the inner conductor, and the like, may be accommodated by the deformation of the screw, and the bearing surface of the inner conductor is brought into contact with a bottom surface of an outer conductor evenly and reliably, thereby suppressing intermodulation distortion from occurring.

Abstract: A balanced filter suitable for a reduction of the filter size. The balanced filter comprises strip-line resonators (SL1a, SL1b) constituting resonance electrodes on the unbalanced side, strip-line resonators (SL2a, SL2b) disposed in adjacently opposed relation to the strip-lines on the unbalanced side and constituting resonance electrodes on the balanced side, strip-line resonators (SL3a, SL3b) disposed in adjacently opposed relation to the strip-lines on the balanced side and constituting stage constituting resonance electrodes, and impedance elements (Z) coupling the resonance electrodes on the balanced side to the stage constituting resonance electrodes.

Abstract: A filter includes a resonant unit which has a plurality of resonators respectively formed of each microstrip line and connected in cascade with one another, and a coupling unit which has at least one inter-resonator coupling of the resonant unit in an area within a range of ±45° (?-wavelength) in an electrical length from a voltage maximum point at a intermediate of the microstrip line.

Abstract: A surface acoustic wave device is provided. The surface acoustic wave device includes a piezoelectric substrate and an IDT which is disposed on the piezoelectric substrate and made of Al or an alloy containing Al as a main component and using an SH wave as an excitation wave, wherein the piezoelectric substrate is a rotated Y-cut quartz plate having a cut angle ? set to a range of ?64.0°<?<?49.3° rotated counterclockwise from a Z crystalline axis and a propagation direction of a surface acoustic wave set to a direction of 90°±5° with respect to an X crystalline axis, wherein, when a wavelength of an excited surface acoustic wave is denoted by ?, an electrode film thickness H/? normalized with wavelength of the IDT is set to a range of 0.04<H/?<0.12, and wherein, when a line occupancy rate mr of electrode fingers constituting the IDT is defined to be electrode finger width/(electrode finger width+electrode finger spacing), the line occupancy rate mr is set to a range of 0.53?mr?0.65.

Abstract: An oscillator comprising a dielectric resonator (DR) has a high controllability and reproducibility of coupling between the dielectric resonator (DR) and an oscillation circuit, and an integrated circuit is reduced in size. The dielectric resonator (DR) (1) is composed of a dielectric substrate (2), grounding conductive layers (3a, 3b) formed on both sides of the dielectric substrate (2), and via holes (4a) for electrical connection between the conductive layers. A coupling element (7a) composed of a slot (5a) provided in the central portion of the grounding conductive layer (3a) and a patch (6a) surrounded by the slot (5a) is coupled to the dielectric resonator (DR) (1). The patch (6a) is connected to a transmission line (13a) on an oscillation circuit (9) through a bump (8). The transmission line (13a) is connected to the ground through a termination resistor (15a).

Abstract: In order to achieve miniaturization without degrading Q of a dielectric filter in the present invention, resonant elements has upper and lower ground electrodes. The upper ground electrode is formed of upper ground electrodes which correspond to wide portions and have no pattern formed on a portion corresponding to narrow portions, and an upper ground electrode which corresponds to the narrow portions and formed higher than the layer of the upper ground electrodes. The lower ground electrode is formed of lower ground electrodes which correspond to the wide portions and have no pattern formed on a portion corresponding to the narrow portions, and a lower ground electrode which corresponds to the narrow portions and formed lower than the layer of the ground electrodes.

Abstract: A filter element includes a coil part formed in an overall tubular shape by layering a pair of signal transmitting belt-shaped conductors and a grounding belt-shaped conductor with a belt-shaped insulator in between and winding so that the grounding belt-shaped conductor is outside a pair of signal transmitting belt-shaped conductors, a magnetic body attached to a center of the coil part; a pair of input terminals that are connected to respective outermost circumferential parts of the pair of signal transmitting belt-shaped conductors and are respectively led from outer circumferential positions of the coil part; a pair of output terminals that are connected to respective innermost circumferential parts of the pair of signal transmitting belt-shaped conductors and are respectively led from central positions of the coil part located on an opposite side to leading positions of the pair of input terminals with the magnetic body in between; and a grounding terminal that is connected to an outermost circumferentia

Abstract: A base band of a ?a wave generated by a ?a/4 resonator is used as it is, a triple wave of the ?a wave generated by the resonator is shifted to a low frequency side, and the fundamental wave and the triple wave are complemented by a pass band, generated by a ?b/2 resonator. Consequently, a flat pass characteristic is secured in a band from the fundamental wave to the triple wave.

Abstract: The invention comprises a technique and associated mechanisms by which dielectric resonator circuits, such as filters, can be tuned in both frequency, bandwidth or both without the need for irises, tuning screws and/or tuning plates. In accordance with the invention, the positions of the dielectric resonators are adjustable relative to each other within the cavity in multiple ways, including vertically and horizontally. The dielectric resonators also may tilt relative to each other. Furthermore, an off-center longitudinal hole can be machined in one or more of the dielectric resonators so as to make the electromagnetic field of the resonator non-uniform so that the dielectric resonator can be rotated about its longitudinal axis to alter the coupling between dielectric resonators.

Abstract: A description is given of a high frequency filter comprising microstrips. The filter comprises at least two resonators (16, 18) which each have, as frequency-determining elements, a first straight microstrip section (28) and a second straight microstrip section (30), which are parallel next to each other, and also a capacitor assembly (22). In each resonator the capacitor assembly is connected between first ends of the microstrip sections and each resonator is exclusively connected to ground at the second ends of the microstrip sections. In each resonator (16, 18) the sum of the two microstrip sections acts as inductive lement. The resonators (16, 18) therefore act in the same manner as a resonator having a single microstrip, the length of which corresponds essentially to the sum of the lengths of the first microstrip section (28) and the second microstrip section (30). This construction of a filter allows a shorter design compared to conventional filter structures.

Abstract: An RJ 45 connector for unshielded CAT5 cable has electromagnetic-interference-suppression circuitry to meet the Class B conducted and radiated emissions standard. The connector comprises, in addition to signal-conditioning transformers, a current-blocking ferrite and a plurality of pairs of common-mode filters, one pair for each conductor of each active twisted pair of the cable. Each pair of filters is connected in series with each other between a conductor of an active twisted pair and a transformer winding, and meets or exceeds the impedance, reactance, and resistance curves of FIGS. 2-4. The ferrite is connected in series with each conductor of each inactive pair of the cable and across a capacitor to ground, and meets or exceeds the impedance, reactance, and resistance curves of FIGS. 5-7.

Abstract: Systems and methods are taught for blocking the propagation of electromagnetic waves in parallel-plate waveguide (PPW) structures. Periodic arrays of resonant vias are used to create broadband high frequency stop bands in the PPW, while permitting DC and low frequency waves to propagate. Some embodiments of resonant via arrays are mechanically balanced, which promotes improved manufacturability. Important applications include electromagnetic noise reduction in layered electronic devices such as circuit boards, ceramic modules, and semiconductor chips.