Abstract: A high-frequency filter employing helix resonators and a metallic or metallized cover. The cover contains at least two helix-shaped resonator coils separated from each other by a metallic or metallized partition provided with an aperture which there is a tuning strip, by reducing the size of which the size of the aperture can be enlarged and thereby the electrical coupling between the resonators adjusted.

Abstract: A notch filter having increased pass band characteristics is provided by insertion of an inductor between a normally-grounded capacitor and ground, the capacitor being connected to an inductive-capacitive filter network. By this construction, the equivalent capacitor of the high-frequency equivalent circuit is not connected directly to ground, but rather has the inductor interposed between it and ground. This significantly increases the pass band of the circuit.

Abstract: A block-substrate dielectric filter with an a wider VHF range and better capacitive performance is set forth. A capacitive matrix situated in a dielectric substrate (102) that is operably attached to a block (104) filter provides more accurate shunt and series capacitances, and allows design of improved narrowband filters.

Abstract: An airline transmission structure in a low temperature co-fired ceramic ("LTCC"). A cavity is made within the LTCC structure. Ground planes surround the cavity. Electronic processing circuitry, such as an airline filter, is suspended within the cavity. Transmission lines are provided to connect the electronic circuitry to the electronic signals (typically microwave) which require processing. Full integration of the airline filter with other electronic circuitry in a single LTCC package is also shown.

Abstract: A magnetic core for a signal line filter adapted to be assembled in a terminal connector for a signal line cable for connecting electronic devices to form a signal line filter, wherein the magnetic core is provided with pin insertion holes each having a tapered portion in the direction of thickness of the magnetic core, or tapered portions at both sides in the direction of thickness of the magnetic core.

Abstract: A multidielectric electrical filter is adapted for passing a primary electrical signal at a first frequency while attenuating higher frequency signals, most notably harmonic spurs. The filter comprises an elongated transmission line and one or more radial pads overlying a first surface of a dielectric support opposite a ground plate. The support is formed of a first dielectric material to achieve a desired capacitive coupling between the pad and the ground plate effective to attenuate the higher frequency signals. The support further comprises a region underlying the transmission line and containing a second dielectric material having a dielectric constant distinct from the first material. Preferably, the region includes one or more slots containing air to minimize the capacitive coupling between the transmisison line and the ground plate and thereby reduce insertion loss of the primary signal that would otherwise lessen the power of the signal to the antenna.

Abstract: An interdigital resonant cavity filter structure is foled to provide two adjacent chambers physically positioned side by side and electrically connected in series with each other. A center plate divides the two chambers with a slot at one end of the structure to permit the two chambers to function as one resonant cavity in a folded relation to each other. Each chamber includes interdigital resonators which are related to the overall resonant cavity to produce a band pass filter action within the folded resonant cavity. The input of the filter structure is applied through a port of a circulator connected to one end of the resonant cavity and the output is taken from another port of the circulator. The opposite end of the resonant cavity is terminated in the characteristic impedance of the resonant cavity thereby causing the overall structure to operate as a high quality notch filter.

Abstract: A planar filter array includes a single monolithic alumina substrate having a plurality of counter bores on each side connected by central bores to form passages for insertion of connector pin contacts. The connecting bores contain ferrite beads and the counter bores contain discoidal capacitors which sandwich the ferrite beads to form pi filter circuits for filtering the pin contacts. Grounding electrodes on the discoidal capacitors are soldered to a grounding layer or traces on the substrate to provide a ground path for the fiters.

Abstract: A dielectric filter includes a homogeneous monolithic block of dielectric material having a plurality of parallel extending dielectric resonators formed therein. A plurality of first electrodes extend alond the top surface of the monolithic block, each encompassing an opening in the monolithic block defined by a corresponding one of the plurality of dielectric resonators. Either the distance between adjacent dielectric resonators or the configuration of the first electrodes is established to cause an overcoupling based on the coupling impedance, thereby tuning an attenuation pole of the dielectric filter to a finite frequency. Additionally, second electrodes are provided along the top surface of the monolithic block extending between and spaced from the first electrodes and connected to a ground electrode.

Abstract: A ceramic filter (10) can be surface mounted. Input/output pads (18 and 20) through which electrical signals pass are located on one surface of a block of dielectric material (12) to permit use of the so-called surface mount manufacturing techniques. No wired connections to the ceramic bandpass filter block are required.

Abstract: A dielectric filter includes: a plurality of coaxial resonators and external connectors; each of the coaxial resonators includes a dielectric block having an outer peripheral surface and an inner peripheral surface parallel to a common axis and having two end faces, a conductive layer formed on the outer and inner peripheral surfaces and on one of the end faces, and a depressed part for accepting the external connection means and formed by removing a portion of the conductive layer on at least the outer peripheral surface in the vicinity of the other end face; and the external connectors includes a dielectric substrate, and an external connection electrode formed on the dielectric substrate and capacitance-coupled with the conductive layer on the inner peripheral surface.

Abstract: A bandpass filter which lends itself to applications in the 500 megahertz to 1 gigahertz region. The filter utillizes the capacitively coupled bandpass filter as a model in the design process, but replaces the lumped element inductor/capacitor resonators with distributed stepped impedance resonators.

Abstract: An audio signal transmission line comprising an additional inductance inserted in series with the line and/or coupled in parallel therewith near the load end of the line for providing a low pass filter which overcomes parasitic and dielectric capacitance of the line so as to reduce audio frequency noise generated in the line by low level and low frequency audio signals. The magnitude of the inductance used may vary widely, e.g. from 20 microhenries to 1 millihenry, depending on the length of the line and the space available.

Abstract: Microwave and millmeter-wave system components are fabricated by using slotlines extending from the periphery of CPW resonators. This technique permits the degree of electrical coupling between the CPW and and the slotlines to be adjusted for matching, and the CPW resonators and slotlines behave as if they were relatively independent circuit elements, permitting transmission line models to be useful design tools and predicting the behavior of the system components. The system components are fully planar and allow easy integration of active and passive semiconductor devices in series with the CPW, and in shunt across the slotlines in hybrid and monolithic circuit forms. This technique also enables the conductive plane to be split for biasing semiconductor devices coupled to the CPW resonators for microwave and millimeter-wave power generation, tuning, mixing, filtering, frequency multiplication and switching.

Abstract: A transmission line filter is provided which includes a first resonator having open ends being coupled to a second resonator disposed on a substrate. A transmission zero frequency is tuned by means of a varactor which is coupled between the first and the second resonator. The first resonator includes a terminal for applying a control voltage to the varactor for varying its capacitance.

Abstract: A choke for reducing common mode signals in high frequency circuits. A microstrip transmission line includes a pair of conductors spaced above a ground plane conductor. In input and output regions the conductors are spaced relatively far apart from each other such that each conductor presents a characteristic impedance that is similar for common mode and for differential mode signals. Between the input and output regions the conductors are located much closes together such that they present different characteristic impedances to common mode and to differential mode signals so as to reflect the common mode signal but not the differential mode signal. In another version a hole in the ground plane beneath the conductors is partially occupied by a conductive island that is coupled to the ground plane through a resistance to absorb the common mode signal rather than reflecting it. Other versions are realized in a pair of parallel coaxial cables and in a coplanar transmission line.

Abstract: A high-frequency band-pass filter has an input resonator, a middle resonator and an output resonator which are coupled in parallel. The input resonator and the output resonator are capacitively shortened quarter-wave line resonators. To improve the attenuation characteristics, the middle resonator is designed as a capacitively shortened half-wave resonator. The input resonator extends along a first part of the length of the middle resonator. The output resonator extends along a second part of the length of the middle resonator.

Abstract: A dielectric resonator device comprising a resonator body having a dielectric resonator element of dielectric ceramics, and a supporting member integrally formed with the resonator element and made of the same material as that of the resonator element, the resonator element being provided with an inner hole, if necessary.

Abstract: A dual mode microstrip resonator (1) usable in the design of microwave communication filters. The substantially square resonator (1) provides paths for a pair of orthogonal signals which are coupled together using a perturbation located in at least one corner of the resonator (1). The perturbation can be introduced by notching (3) the resonator (1) or by adding a metallic or dielectric stub (5) to the resonator (1).

Abstract: A filter apparatus in accordance with the present invention comprises, for example, a band-pass filter and a plurality of band-stop filters connected as the post-stage to the band-pass filter. The band-pass filter transmits a band containing a desired frequency band, and the band-stop filters attenuate undesirable frequency bands. Another filter apparatus in accordance with the present invention comprises, for example, a first band-pass filter, a circulator connected to the first band-pass filter, and second band-pass filters connected to the circulator. The first band-pass filter transmits a band containing a desired frequency band to the circulator, and the second band-pass filters transmit undesirable frequency bands and reflect the desire frequency band to the circulator. The desired frequency band is outputted from this circulator. Still another filter apparatus in accordance with the present invention comprises, for example, a circulator and a band-pass filter connected to the circulator.