Abstract: A microwave band-pass filter of interdigital type employing microstrip lines and a filter characteristic adjusting method thereof are disclosed. The microwave band-pass filter includes plural stages of resonant lines. Furthermore, the resonant line includes a short-circuit portion, an open portion and a connection portion. The short-circuit portion has its one end grounded and the open portion has its one end open. The connection portion is interposed between the short-circuit portion and the open portion and has its width gradually increased from both sides of the short-circuit portion to both sides of the open portion.

Abstract: A tunable bandpass filter comprises a flat ferrite body having first and ond spaced, coextensive microstrip conductive lines on its upper surface. A winding encircles the ferrite and conductive lines so that a variable d-c current in the winding varies the magnetic permeability of the ferrite and thus the center frequency of the filter.

Abstract: A method of adjusting a frequency response in a filter device of a three-conductor type having a pair of stacked dielectric substrates with a plurality of stripline resonator conductors being sandwiched therebetween, wherein the frequency adjusting of the filter is performed by partially removing an open circuit end of each resonator conductor and at need by adding an compensating conductor member to the partially removed open circuit end portion of each resonator conductor.

Abstract: A method of adjusting a frequency response in a filter device of a three-conductor type having a pair of stacked dielectric substrates with a plurality of strip-line resonator conductors being sandwiched therebetween, wherein the frequency adjusting of the filter is performed by partially removing the ground conducting layer provided on the peripheral portion of each dielectric substrate at regions corresponding to the open circuit ends, or to the open circuit ends and the short circuit ends of the resonator conducting layers.

Abstract: A method of adjusting a frequency response in a stripline filter device having a pair of stacked dielectric substrates with a plurality of stripline resonator conductors being sandwiched therebetween, wherein the frequency adjusting is performed for each resonator conductor under the condition that the resonator conductor(s) adjacent to one to be determined is electrically connected via a fine strip member to the ground layer, thereby correctly tuning the frequency response of each resonator conductor without any influence of the other resonator conducting layers.

Abstract: A switchable resonator device having a selectable center frequency over a wide radio frequency range comprising a radio frequency signal input and output means, a resonator structure connected between the signal input and output means for respectively receiving and delivering radio frequency input and output signals, the resonator structure using a strip line conductor having a first conductor element with first and second extending portions each providing respective inductance properties, a first switchable means for controllably connecting the first portion of the first conductor element at selected locations along its extension with the second element for varying its inductive properties, a second switchable means for controllably providing a selected capacitance between the second portion of the first conductor element and the second conductor element, and control means providing a control signal to the first and second switchable means for selecting and changing the center frequency of the resonator devi

Abstract: A radio frequency duplexer filter for a duplex transceiver is disclosed. To prevent spurious signals conducted by flyback responses of the transmit bandpass filter 103 from reaching the antenna (105), a band reject circuit consisting of third harmonic quarter-wave transmission line stubs (601 and 603) are advantegeously coupled to an output transmission line (107). Likewise, to prevent spurious signals conducted by flyback responses of the receive bandpass filter (113) from reaching the receiver (109), a band reject circuit consisting of third harmonic quarter-wave transmission line stubs (605 and 607) are advantageously coupled to an input transmission line (111).

Abstract: A band pass filter is comprised of one or more filter units each having a V-shaped microwave strip line provided with two variable capacity elements at its two open ends and a high frequency elimination element connected to the apex thereof through which a control voltage for the variable capacity elements is applied.

Abstract: A bandpass filter is disclosed which comprises a pair of opposing, first and second dielectric substrates each having an outer surface provided with a ground conductor, and a conducting resonator member provided between the first and second dielectric substrates and including a plurality of parallel resonator fingers each having an open circuit end and a base end electrically connected to said ground conductor, characterized in that a part of the ground conductor is removed to form an opening therein between adjacent two fingers, thereby to increase the bandwidth of frequency to which the filter responds.

Abstract: A ferromagnetic resonance device is disclosed which utilize the perpendicular resonance of ferrimagnetic YIG thin film operable under a D.C. bias magnetic field perpendicular to a major surface of the YIG thin film element. By making the YIG thin film to have a major surface thereof (100) crystal plane of YIG or (111) crystal plane of a substituted YIG having reduced Ku value, lower limit of resonance frequency is extremely lowered. Thus wide range variable filter device can be obtained.

Abstract: A filter device of a three-conductor structure type having a stripline pattern resonator consisting of a plurality of juxtaposed resonator conductors between two dielectric substrates which are stacked to each other, each of said dielectric substrates being provided with an outer conductor layer which surrounds the the outer surface and side portion thereof and is connected to one ends of the juxtaposed resonator conductors, and openings for adjusting the frequency of response of the filter, each frequency adjusting opening being provided on the lateral portions of the outer conductor layers corresponding to said one end of the each resonator conductor. A conductor strip for increasing the frequency of response of the filter can be removably applied to each frequency adjusting opening.

Abstract: In a thin film ferromagnetic resonance tuned filter is disclosed which comprises a ferrimagnetic thin films, input and output signal transmission lines respectively coupled with the ferrimagnetic thin films, and a magnetic circuit for applying a DC magnetic field to the ferrimagnetic thin films, the present invention expands the variable frequency band by forming extensions each extending from the signal transmission line so that the distance from the coupling point of the signal transmission line coupled with the corresponding ferrimagnetic thin film to the grounded end thereof is 1/10 or above and less than 1/4 the wavelength of a wave transmitted in the transmission lines at the upper limit frequency of a tuning frequency band. Further the deterioration of the isolation characteristics is suppressed by bending the extended portions not to form parallel portions to another transmission line.

Abstract: A filter employing Triplate type microstripline as the base element comprises first and second dielectric substrates which are superposed with each other so as to hold a resin sheet therebetween, and are contained in a metal case. The respective dielectric substrates are provided on outer major surfaces with ground electrodes to be electrically connected with the metal case. Resonance electrodes are provided on inner major surfaces of the respective dielectric substrates to be electrically connected with relating ground electrodes through end surfaces of the dielectric substrates. The resin sheet holds metal pins passing through the same along the direction of thickness thereof, so that the respective resonance electrodes of the first and second dielectric substrates are electrically connected with each other by the metal pins.

Abstract: An LC filter includes a dielectric base plate having throughholes, and pluralities of first and second inductance conductors are formed on the both main surfaces of the dielectric base plate, respectively. The respective first and second inductance conductors are paired by being electrically connected through the througholes and, thereby a plurality of inductors are formed. A capacitor is formed by first and second capacitance electrodes which are formed on both main surfaces of the dielectric base plate at positions opposing each other. The plurality of inductors and the capacitor are suitably connected. First and second additional electrodes are formed on both main surfaces of dielectric base plate at positions opposing each other so that a capacitor for trimming is formed by the additional electrodes. The capacitor for trimming is connected in parallel with at least one of the plurality of inductors.

Abstract: Integratable microwave devices such as a tuneable band reject filter or an r.f. switch are provided on a gallium arsenide substrate having a (100) orientation. Each of the devices includes a layer of a ferromagnetic material having a pair of easy axes which lie in the plane of said (100) orientated substrate and a layer of a conductive, nonmagnetic material disposed thereover. The ferromagnetic material has a ferromagnetic resonant frequency related to the applied DC magnetic field, the anisotropy field, the saturation magnetization, and gyromagnetic ratio. Such devices are provided by utilizing the ferromagnetic resonant properties of the ferromagnetic material disposed on the (100) substrate.

Abstract: An adjustable band filter comprising a conductive screening body (10, 11) made of two parts (10 and 11) joined to each other on either side of a separation plane (13), a cavity (12) inside said body, said cavity containing a half wavelength resonant line (15) carried on a first face (16) of a suspended substrate (14), the substrate being end-coupled and received in grooves (17) made in the walls of the first portion (10). The first face (16) of the substrate (14) divides the cavity (12) into two asymmetrical volumes in such a manner as to enable the passband of said filter to be modified.

Abstract: A voltage tunable bandpass filter consisting of a plurality of parallel resonators electromagnetically coupled and having tuning diodes coupled to a first end. The resonators are DC isolated at a second or RF grounded end of each resonator. A voltage source reverse biases the tuning diodes from the second or less critical end of the resonators.

Abstract: A tunable, microwave filtering device comprises a microstrip line, a dielectric resonator capable of being coupled to the microstrip line, a coplanar line capable of being coupled to the resonator, an active element, such as a varactor for example, mounted on the coplanar line, the variable impedance of which enables the frequency tuning of the device. The invention can be applied to the making of a tunable microwave frequency discriminator, the making of a microwave oscillator and the frequency stabilization of a tunable oscillator.

Abstract: A tuneable microwave filter comprises two branches of the same type each of which is connected to ground (22, 24) at each end and each of which includes a series-connected variable capacitance diode (13, 13A) controlled by a D.C. signal (V), said filter being disposed on the first face (9) of a plane substrate (8), with each branch comprising in series:a micro-strip transmission line (11, 11A);a second variable capacitance diode (12, 12A) situated between the first diode (13, 13A) and the micro-strip transmission line (11, 11A); andthe input (E) and the output (S) of said filter taking place at the points interconnecting the micro-strip transmission lines (11, 11A) and the second variable capacitance diodes (12, 12A) of respective ones of the first and second branches. The filter is applicable, in particular, to space telecommunications.

Abstract: A tunable coupled transmission line band reject filter for use in the microwave frequency range includes a coupled transmission line having first and second line sections. Each line section has an input end and an output end. A transmission line exhibits a natural notch at a particular frequency. A first varactor is coupled between the input ends of the first and second sections. A second varactor is coupled between the output ends of the first and second sections. A D.C. bias voltage across the varactor diodes controls the center frequency of the resulting notch filter.

Abstract: A multiband microwave filter that can selectively transmit a broadband signal or any discret or combination of predefined frequency bands. The filter has two transmission lines, with an output port at one end of a first one of the transmission lines. A switch selectively transmits an input signal to one of the transmission lines. The filter also has a plurality of narrowband directional filters, each of which is used to transmit signals in a corresonding frequency band from one of the transmission lines to the other. Each directional filter includes at least one diode for enabling and disabling the operation of the direction filter in accordance with a bias voltage applied to the diodes. By controlling the switch and applying appropriate bias voltages to each of the diodes, the microwave filter can selectively transmit a broadband signal or any discret or combination of the frequency bands transmitted by the directional filters.

Abstract: A microwave filter having a filtering effect against specific frequencies is fabricated by erecting a second dielectric substrate on the upper surface of a first dielectric substrate, a resonating circuit is formed by locating strip lines facing towards each other on both surfaces of this second dielectric substrate, and the strip lines are connected to input and output lines on the first dielectric substrate.

Abstract: A voltage tumble filter has several parallel coupled half wavelength lines. Each open end of a line is coupled to ground through a corresponding varactor. Voltage may be distributed to the varactors through a thin wire attached a quarter wavelength from each varactor.

Abstract: A monolithic signal scrambler comprising a transmission line section formed on a ceramic substrate, including resonant line sections disposed adjacent to the transmission line path on the substrate and selectively energized to cause a predetermined signal loss through the conductive transmission line path according to the resonant frequency of the activated resonant line sections. The scrambler according to one embodiment of the present invention includes 12 resonant line sections, each tuned to approximately coincide at the preferred frequency, whereupon the loss caused by the activated resonant sections adds a significant signal loss through the transmission line path at a particular selected frequency. As a result, when used as part of a TV cable distribution system, selective activation of the scrambler provides effectively complete suppression of a selected premium signal channel while maintaining accurate control of the signal attenuation characteristics in the process.

Abstract: This highly reproducible stripline band-pass filter comprises, between its two leads (A and B), n halfwave resonators (1-7) connected in series. Suitable capacitors (C0-C7) provide a powerful coupling between the successive elements of the series circuit. Quarterwave resonators (10, 11, 70, 71) each having one end connected to the series circuit provide a steep-edge amplitude/frequency response at the limits of the pass-band of the hyperfrequency, wideband filter so obtained.

Abstract: The invention relates to a variable capacitance element operating in the ultra-high frequency range. In order to integrate this element on to an integrated circuit chip, the element is designed so that the control voltage does not interfere with the ultra-high frequency signal and has neither filters nor shock chokes which are not integrable. The element according to the invention utilizes the junction capacitances variation of at least one diode, reverse-biased by a voltage across a resistor, the high frequency signal being at the diode anode. The element construction comprises an active zone in a semiinsulating substrate. Two metallizations partly cover the active zone and form therewith at least one diode. A projection to the active zone forms the resistor, to which is applied the control voltage. The diodes are p-n junctions of schottky diodes. The semiconductor material is Si or from the III-V group. Application to oscillators, filters, phase shifters, etc. in ultra-high frequency equipment.

Abstract: The invention relates to a device for the fine adjustment of a resonant microstrip-line formed on an insulating substrate (2), tuned by a varicap diode (7,8) which makes it possible to adjust the shape of the curve representing the tuning frequency of the strip line as a function of the direct voltage controlling the diode. One or more blind holes are provided in the surface of the substrate opposite the strip line, and a base part (15) with one or more threaded holes, into which cylinders are screwed, is fitted under the strip line. The cylinders are placed facing the blind holes and are aligned with the holes to enable entry into them. The cylinders and the base part are electrically conductive and connected to ground.

Abstract: A microstrip antenna or other microstrip device has a planar electrically-conductive region on the surface of a dielectric board. The device is tuned by silk-screen printing one or more layers of a dielectric ink/paint over the surface of the device. This produces layers of a predetermined thickness which each reduce the frequency of tuning of the device by a predetermined amount until the desired frequency is achieved.

Abstract: A high power tunable filter, for use in a frequency hopping system, is described and includes a transmission line having an input for receiving a high power level input signal to be filtered, and an output. The filter includes a plurality of resonators, each parallel-coupled to the transmission line, and driven by an associated electronic tuning network. Each of the electronic tuning networks includes a plurality of tunable reactive elements and PIN diodes, each PIN diode connected to one of the tunable reactive elements to enable this diode to connect its associated tunable reactive element in and out of the tuning network, thereby controlling the resonant frequency of the resonator associated with the tuning network. An electronic control circuit is also provided for controlling the frequency of the tunable filter.

Abstract: A method is provided for adjusting the electrical characteristics and particularly the frequency of a microstrip-line printed filter with distributed constants. The method consists in depositing a strip of dielectric material on all the microstrip resonators of the filter.

Abstract: Apparatus for varying the magnetic field in a magnetic resonant element which comprises a magnetic yoke with one or more magnets mounted within the magnetic yoke so as to generate a substantially uniform magnetic field in the magnetic yoke and a plurality of magnetic resonance elements located in the magnetic field formed by the magnet and including adjusting means for varying the magnetic reluctance between the magnetic yoke and the magnet at a position which is opposite the position of the plurality of magnetic resonance elements. The magnetic reluctance can be varied to arrive at the desired strength of the magnetic field.

Abstract: A length of transmission line having a plurality of capacitors and a plurality of shorter lengths of transmission line coupled thereto by pin diodes which are individually operable to connect any combination of capacitors and transmission lines to the basic transmission line for changing the center frequency thereof in incremental steps across a desired band of frequencies.

Abstract: The microwave filter comprises resonators constituted by capacitor-coupled rejector circuits. The tuning and coupling capacitors are composed of parallel metal plates supported and separated by the dielectric of a substrate. The surface of at least one plate of each tuning and/or coupling capacitor is provided with windows which can be sealed-off by a metal deposit in order to permit adjustment of each capacitor to its optimum value.

Abstract: A dielectric resonator 11 is tuned by varying the magnetic flux induced into a magnetically saturable shield 12 mounted adjacent the resonator by varying the flow of current through a coil 17.

Abstract: A magnetically tuned resonant circuit for coupling r.f. energy between input and output coupling circuits thereof in a first mode of operation and isolating such energy between such coupling circuits in a second mode of operation includes a current path circuit provided to selectively change the resonant frequency of the magnetically tuned resonant circuit. In a first embodiment of the current path circuit, a microstrip transmission line used to form one of such coupling circuits, having a pair of planar spaced strip conductor portions adjacent a resonant body, is configured to provide the current path around such body. In the presence of an external magnetic field H.sub.DC, a pulse of current is fed around the current path and in response thereto provides a pulse magnetic field H.sub.DCp in the region of the resonant body. Such field H.sub.DCp either aids or opposes the external magnetic field H.sub.DC and in response thereto shifts a resonant frequency .omega..sub.

Abstract: A slotted line tunable microwave filter of the type having a metallic layer aving slot patterns thereon, and an insulating layer, the filter also including a variable bias D.C. magnetic field source, for imposing a magnetic field on a dielectric junction in the metallic layer, which may be varied to tune the filter resonant frequency.In one embodiment of the invention the slot pattern comprises a first set of slots and a second set of slots.The first set of slots comprises a first slot disposed coincident with a negative x axis and the second set of slots comprises a second slot disposed coincident with a positive x axis.

Abstract: A microwave filter comprising linear resonators makes use of proximity-coupled conductors situated on the first surface of a substrate of dielectric material, whose second surface parallel to the first surface is metallized to form a ground plane, in order to form the resonators. The extremities of each conductor are connected to the earth plane and the center of each conductor is equally connected to the earth plane via at least one capacitor.

Abstract: A high frequency tuning filter having a grounding conductive layer on one side of a dielectric substrate and figure eight (8)-shaped resonance electrodes of an electrically conductive film layer on the other side is improved into a variable tuning filter for a high frequency circuit which has a plurality of resonators surrounded by figure 8-shaped grooves respectively which are each formed in the electrically conductive layer in such a manner that a portion of an electrically conductive layer small in width remains in the figure 8-shaped groove and the electrically conductive layer remains between the adjacent resonators, and which also has a region formed by removing a part of the grounding conductive layer over the resonators.

Abstract: An apparatus and method for selectively orientating a ferrimagnetic body along a selected temperature invariant crystallographic axis includes a first pair of coils disposed for producing a magnetic field along a first direction, and a second pair of coils disposed within the first pair of coils for producing a magnetic field along a second direction, the direction of such second field being displaced at a predetermined angle .theta., with respect to the direction of said first field. A platform upon which the ferrimagnetic body is supported is disposed at an intersection of such fields and has a surface disposed at a predetermined direction with respect to a horizontal plane. A series of alternate pulsed magnetic fields is generated in turn by each pair of coils and the body rotates in response to each one of such fields. After pulsed fields have been generated, the so-called "easy axis" of the crystallographic structure of the body is aligned with the axis of the coils.

Abstract: A method and corresponding apparatus for maintaining constant bandwidth over a frequency spectrum in a microwave, dielectric resonator waveguide filter. Bandwidth is determined by the product of the resonant center frequency and the interresonator coupling coefficient. To maintain constant bandwidth while changing center frequency, the interresonator coupling coefficient must be chosen such that it varies inversely with changes in center frequency. The interresonator coupling coefficient is a function of the physical dimensions of the waveguide and the dielectric resonators, the dielectric constant and the spatial location of the resonators within the waveguide. Once the physical and spatial parameters have been established, the center frequency of the filter may be adjusted by altering the thickness of the resonators without changing the filter bandwidth.

Abstract: The invention relates to devices utilizing magnetostatic waves. The invention has as its object a filter microtape which is able to pick up and selectively dissipate magnetostatic waves as a function of their wavelength. The filter microtape is permeable to waves of which the wavelength is a submultiple of its width. The invention is applicable in particular to tunable magnetostatic wave devices such as delay lines, resonators and oscillators.

Abstract: Resonators magnetically tunable over a broad rf frequency range capable of operation at relatively low rf frequencies (VHF band) are disclosed as well as tunable devices based on them. The resonators comprise a resonator body made of a ferrimagnetic single-crystal material which is generally flat, and is generally rotationally symmetrical with respect to an axis of rotation, for example disk-like or oblate spheroidal-like. The axis of rotation of the resonator body is oriented with respect to the crystalline lattice in a particular way depending on the anisotropy. The same orientation is required for the dc field whose magnitude determines the resonance frequency. The resonators are particularly useful in broadband tunable rf and microwave filters and oscillators, and can be tuned by means of the dc field to resonate from about 50 MHz to several GHz.

Abstract: A magnetically tuned resonant circuit for selectively coupling radio frequency (r.f.) energy between an input coupling circuit and an output coupling circuit, dielectrically spaced from the input coupling circuit, through a resonant body disposed therebetween. Each coupling circuit includes a center strip conductor portion dielectrically spaced from a ground plane conductor. Such center strip conductor and ground plane conductor of each coupling circuit are formed on a common surface of a corresponding dielectric. The center strip conductor portions are orthogonally orientated, and have first end portions which are coaxially aligned and terminated with the ground plane. The resonant body is dielectrically supported between each one of such first end portions of such center conductors.

Abstract: Stray capacitance is reduced in a wideband tunable oscillator network by arranging the resonant circuit as one or more series circuit branches wherein a variable capacitance such as a varactor diode is interposed between two substantially identical inductors. In the disclosed VHF-UHF oscillator, the inductors are realized by TEM transmission lines of the stripline variety. The stripline is formed by a multilayer printed circuit board arrangement and two resonant circuit branches are interconnected in a manner that permits biasing of the varactor diodes without the use of blocking capacitors in the resonant circuit path.

Abstract: The variation in the external bandwidth of input and output resonators of YIG filters and of single resonator device, is corrected by means of frequency selective impedance transformers. The transformers are comprised of specific impedance transmission lines which may be incorporated as integral parts of the YIG filter RF circuit.

Abstract: An electromagnetic filter assembly comprises a transmission line electromagnetically coupled to a dual mode resonator having a means for differentially tuning the two modes. The filter may be incorporated in a microwave integrated circuit, and the tuning means may be a movable dielectric slab asymmetrically disposed on the resonator.

Abstract: A combined mounting and tuning structure for a dielectric resonator comprised of a stack of a dielectric resonator body, a resilient body of dielectric material and an electrical tuning conductor. A fastening means preferably in the form of a dielectric screw threadedly engaged in a base wall of an enclosure and by turning the fastening means, the tuning conductor is brought closer to the resonator, and the resonant frequency of the resonator is thereby adjusted while also providing a clamping force on the stack so as to maintain its position relative to the base wall. The dielectric resonator tuner of the invention is shown in oscillator and filter circuit embodiments.

Abstract: Spaced conductive strips are formed on a substrate. A first transmission line transformer is connected between the input and one end of the first strip. A second transmission line transformer is connected between the other end of the first strip and the output. The second strip is connected to ground. A shunt tuning circuit is connected between the strips. The circuit includes first and second MOS capacitors mounted on and connected to the grounded strip. An RF choke interconnects the other side of each capacitor. A varactor diode is mounted on and connected to the first capacitor. An etched spiral inductor connects the varactor and the first strip. A bias signal is applied to the junction between the choke and the second capacitor in order to tune the filter.

Abstract: The disclosure relates to improved filter networks for use in the microwave region employing TTL logic and capable of changing a network from a "bandpass state" to an "all-stop state", or an "all pass state", or from a "low-pass state" to an "all pass state". Provision is also made for the increase or decrease in the selectivity of a low-pass filter.

Abstract: A tunable bandpass filter comprising a pair of slot line resonant cavities formed in a metallic film covering the planar surface of a ferrite substrate. A magnetic biasing field of variable magnitude is generated and applied through the ferrite substrate transversely across the slot line resonant cavities. The magnetic field operates to change the electrical length of the resonant cavities due to the fact that the magnetic permeability of the ferrite material changes with the applied field.