Abstract: A dielectric resonator has a pattern of metallic micro-wave strips deposited onto a dielectric substrate having a high relative permittivity. The pattern is of a generally annular shape and has a slot formed in the annular pattern. The resonator includes an positive feedback circuit coupled thereto having an active element, such as a transistor, and is usable, for instance, as a band-cut off or band-pass filter.

Abstract: Planar dual mode filters (30) are formed by a conductive resonator (20) having circular symmetry and two pairs of symmetrically oriented planar conductive leads (22, 26 and 24, 28). The conductive leads (22, 26 and 24, 28) are aligned colinearly with two orthogonal diameters (32, 34, respectively) of the circular conductive resonator (20) and are electrically isolated from said resonator (20). A perturbation (38) located on an axis (36) oriented symmetrically with respect to the two pairs of conductive lead (22, 26 and 24, 28) couples electromagnetic modes which are injected into the resonator (20) by the planar conductive leads (22, 26 and 24, 28). Higher order filter circuits can be realized by combining multiple filters (30) of the present invention. The filters (30) are amenable to printed circuit (microstrip to stripline) fabrication using superconductors for the conductive elements.

Abstract: A multipole bandpass filter (40) comprises a first microstrip split-ring resonator (12), having at least a first edge and a second edge, the first edge having a gap (20) therein, and an input. The bandpass filter (40) also comprises a second microstrip split-ring resonator (14), having at least a first edge and a second edge, the second edge of the second microstrip split-ring resonator comprising a gap (26) therein and a balanced output (30, 32). The bandpass filter also includes at least one straight line quasi-combline resonator (22), disposed between the first microstrip split-ring resonator, and the second microstrip split-ring resonator.

Abstract: This invention relates to a compact and high performance microwave stripline resonator consisting of a dielectric substrate provided with a strip electrode and a depression coated with an electrode which is connected to an end of the strip electrode provided on one of the surfaces of the dielectric substrate and a grounding electrode provided on the other surface of the dielectric substrate, and the grounding electrode is connected to the other end of said strip electrode. With this dielectric resonator construction, the characteristic impedance of the strip electrode and the characteristic impedance of the electrode coated on the depression are made different. As a result of this, the length of microwave stripline can be shortened without sacrificing the Q of the resonator. This is highly effective to realize compact resonators.

Abstract: A transmission line structure comprises a dielectric substrate (11) having first and second opposing sides separated by a first distance (3). A transmission line (13) is disposed on the first side while an opposed conductor (12) is disposed on the second side. The transmission line (13) has a first edge (4) a second edge (6), and a midde portion (8). Thicknesswise, the middle portion (8) is separated from the opposed conductor by the first distance (3), and at least a portion of the first edge (4) is separated from the opposed conductor by a second distance less than the first distance (3).

Abstract: The stop-band and pass-band frequencies of a duplex filter which includes a plurality of helix resonators must not change when the temperature changes. Therefore the resonators used must be temperature compensated. One known method is to injection-mold plastic bonds (3, 8) to the cover (2) of the resonator shield in such a way that the last turns of the helical coil (4) of the resonator are inside the bond (3, 8). Through a suitable selection of the bonding material it is possible in part to compensate for changes in the distance between the open end of the resonator coil and the cover of the shield and for changes in the pitch of the turns of the conductor (4) wound into a helical coil and in the coil length. In practice this compensation is undercompensated in character. According to the invention it is possible, by making one interval (pitch) (7) between the free turns of the coil greater than the others, to make the temperature compensation just right.

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: 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 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: An LC-type dielectric filter which includes strip lines on a dielectric plate forming distributed constant type resonators. The strip lines and other elements of the filter, such as coupling capacitances are plated onto the dielectric plate as printed circuits to realize a small, high-Q dielectric filter which is suitable for mass-production.

Abstract: A radio frequency antenna for a nuclear magnetic resonance tomography apparatus has interior conductors which form a transmission line resonator with at least one shortening capacitor. The transmission line resonator can resonate at a plurality of resonator frequencies, and a trap circuit is provided for decoupling the interior conductors from the other conductors. The antenna can be operated at a number of different resonate frequencies, for example, at frequency f.sub.1 =170 MHz for protons (hydrogen) and F.sub.2 =69 MHz for phosphorous.

Abstract: A dielectric resonator for surface mounting comprising two dielectric layers; a conductive layer formed on a plane interposed between the two dielectric layers, the conductive layer being lengthy and having an inductance determined by a length thereof; grounding electrode layers provided on outer surfaces of the two dielectric layers; protective layers for covering outer surfaces of the grounding electrode layers; a first outer connecting terminal provided on a surface of a main body of the resonator and electrically connected to an end of the conductive layer and to the grounding electrode layers, the main body comprising the protective layers, the dielectric layers, the conductive layer and the grounding electrode layers; and a second connecting terminal provided on a surface of the main body and electrically connected to a portion of the conductive layer, the portion being far from the above end of the conductive layer.

Abstract: A rigid, monolithic structure for the resonator elements of a tuned stripline segment which may be adjusted by simple, low cost techniques. The resonator elements use a stripline segment (23,24) made from conductive layers of a multilayer printed circuit board. This structure allows the stripline segment to be totally enclosed in a solid, incompressible dielectric material (15,17) which is essentially immune to microphonic effects. A plurality of shorting holes (21) are fabricated at one end of the stripline which serve to short circuit the stripline segment (23) to the ground conductors (18,19) on the layers above and below the stripline segment (23). Adjustment of the resonant frequency is accomplished by removing the plated conductor inside one of the holes at a time, thus removing the short, until the desired resonant frequency is obtained.

Abstract: A microstrip line type resonator includes a rectangular parallelapiped dielectric plate, and a conductive microstrip line disposed on a top surface of the dielectric plate. The microstrip line has opposite ends respectively spaced from front and rear edges of the dielectric plate. The resonator further includes a first grounding layer disposed on an entirety of the bottom surface of the dielectric plate, and a second grounding layer disposed an entirety of the front, rear and side surfaces of the dielectric plate. The first grounding layer is electrically connected to the second grounding layer at the edges of the bottom surface of the dielectric plate. The microstrip line type resonator is a 1/2 wavelength resonator.

Abstract: A band-pass filter for the microwave band consists of a dielectric substrate, a grounded conductor layer formed on the back surface of the substrate, input and output transmission line conductors formed on the front surface of the substrate, and a plurality of .lambda./2-length microstrip conductors formed between the input and output transmission line conductors such that they align in parallel over about .lambda./4 length. A through hole is formed through each .lambda./2-length microstrip conductor, the substrate and the grounded conductor layer at the center of the microstrip conductor. The .lambda./2-length microstrip conductor and the grounded conductor layer are electrically connected to each other through a conductive layer formed on the substrate wall of the through hole.

Abstract: A sensor for measuring magnetic flux has at least one hole or opening in a strip resonator of superconductive material defining a ring in which a Josephson element is integrated into the strip resonator and coupled thereto so that attenuation in the tank circuit formed by the ring when a standing wave is established in the strip resonator can be picked up capacitively by a further strip conductor.

Abstract: A stripline split-ring resonator bandpass filter comprises first and second conducting layers and first and second substrates connected to each other between the conducting layers. A first stripline ring resonator is located on the top side of the second nonconducting substrate and is coupled to the input port of the BPF. The first stripline ring resonator has a gap located therein. A second stripline ring resonator is also located on the top side of the second nonconducting substrate between the first stripline ring resonator and the output port of the BPF. The second stripline ring resonator has a gap located therein. The first substrate has at least two slots therein to allow lumped capacitors to be placed in the gaps in the first and second ring resonators.

Abstract: A resonator having a strip line, the strip line comprising: a first portion forming an open loop; and two second portions, each provided to each end of the first portion, the second portions facing each other with a given distance therebetween, the distance and length of the second portion being determined such that necessary capacitance is provided. The capacitor is provided instead of a discrete capacitor for saving space and for reducing dielectric loss therein. A second resonator further comprises second and third capacitor having a semicircle strip-line patterns for providing capacitances between ends of the first portion and grounded planes which decrease the resonance frequency so that size of the second resonator are reduced. A third resonator also comprises the first capacitor, but arranged outside of the first portion. Capacitance of the first capacitor can be increased by teeth provided to the second portions.

Abstract: The invention relates to a resonator structure comprising a helix resonator (1) wound of metal wire into a cylindrical coil and supported by a plate (2) of insulating material disposed therewithin. A helix resonator is usually made in the form of a cylindrical coil and supported by disposing within the coil a frame made of a ceramic material or plastic in various ways. This is necessary for providing a sufficient mechanical strength. However, such a structure is difficult and expensive to manufacture in series production especially with smaller resonator sizes. These problems are solved by means of a resonator according to the invention in such a manner that at least a part of the insulating plate (2) comprises an electrical circuit formed by strip lines (3), and that the helix resonator (1) is electrically connected to said circuit.

Abstract: A broadband, varactor-tuned shorted coax resonator is provided with a single point coupling port that facilitates coupling of discrete circuitry to the distributed resonator. The coupling port is defined by adding a second shorted coax line across the end of the first. The outer conductors of the two lines are interconnected. The inner conductors of the two lines are serially coupled and define a coupling gap, either along their length or at their ends, across which discrete circuitry can be connected. In a preferred form of the invention, the discrete circuitry is positioned in a region within the periphery of one of the inner conductors in order to provide an electromagnetic shield for the circuitry.

Abstract: A notch filter comprises a helical transmission line enclosed in a conductive activity, and a high Q capacitor coupled to form a series-resonant circuit. The capacitor is fabricated from a portion of coaxial cable having an outer conductor forming a first plate of the capacitor and an inner conductor forming the second plate of the capacitor. The notch filter is particularly suited for rejecting terrestrial interference in a C-band tuner at an intermediate frequency of about 400 MHz.

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 (40) comprises a first microstrip split-ring resonator (12), having at least a first edge and a second edge, the first edge having a gap (20) therein, and an input. The bandpass filter (40) also comprises a second microstrip split-ring resonator (14), having at least a first edge and a second edge, the first edge being coupled to the second edge of the first microstrip split-ring resonator, and the second edge of the second microstrip split-ring resonator comprising a gap (26) therein and a balanced output (30, 32).

Abstract: The invention relates to a magnetic resonance imaging apparatus comprising an RF coil. A high Q and a high sensitivity are achieved in that the coil consists of separate resonators which are tuned to the same resonance frequency and which are inductively coupled to one another but not conductively connected to one another.

Abstract: An MR examination apparatus has a quadrature coil arrangement which consists of two coil systems and a circuit for decoupling the two coil systems. In such an MR examination apparatus the decoupling between the coil systems is improved in that the circuit comprises a variable capacitor which connects one coil system to the other.

Abstract: A variable characteristic impedance microstrip resonator for use in a tunable oscillator circuit, the resonator having relatively high characteristic impedance near its driven end to maximize tuning range and relatively low characteristic impedance near its opposite end to minimize losses and thus optimize sideband noise performance.

Abstract: A filter having elements with distributed constants is made up of resonators providing two different types of coupling. The use of two types of coupling makes it possible to obtain the desired geometry and in particular to limit the coupling between variable capacitors in the construction of combline filters as well as the construction of filters having two transmission zeros and involving the use of hairpin resonators.

Abstract: A chip for a magnetostatic wave device comprising; a base substrate consisting of a dielectric monocrystalline base plate and a ferrimagnetic monocrystalline film formed on the base plate; an excitation means for magnetostatic waves formed on the ferrimagnetic film when it is given a bias magnetic field and high frequency electric signals; and a reflection means to reflect the excited magnetostatic wave toward the center portion of the film before it reaches at end portions of the ferrimagnetic film.

Abstract: A microwave resonator for operation in the whispering-gallery mode is constituted by a resonant element included in a flat disk having a diameter (2a) which is considerably larger than its thickness (2d). An electromagnetic wave which propagates within the disk is confined between the periphery of this latter and a so-called caustic surface having a smaller radius (a.sub.c). The wave does not radiate to the exterior and the resonator can be placed on a dielectric or metallic substrate. The disk can be hollowed-out within the caustic surface. A resonator can be simulated within the thickness of a dielectric substrate by at least one metallic ring which forms a magnetic short-circuit with the ground plane. Excitation is produced by microstrips or by dielectric image waveguides.

Abstract: An identification device for use in electronic security systems is proposed carrying a planar resonant circuit and suiting for use as a marker means for preventing theft of articles to which it is affixed. The device comprises two counter-turning conductive paths forming CW and CCW spiral patterns (if viewed from the same side) in opposition aligned to each other turn by turn and at least one insulative layer spaced therebetween. Said layer may be absent in lateral turn-to-turn spaces or may at least have a reduced total thickness effective therein; it may at least in part configure as a sheet as well. Due to a minimized metal coverage on its real estate the resonant circuit features a low RF magnetic field deflection and hence a high in-system detectivity.

Abstract: An electromagnetic resonator has two or more non-intersecting, substantially overlapping surfaces of approximately similar size and shape separated from one another by a distance which is small in comparison to the physical extent of the surfaces. One or more substantially non-intersecting, electrically conductive paths cover substantial portions of each surface. The widths of the paths are substantially smaller than the physical extent of the surfaces. No path on any one of the surfaces is electrically connected to a path on any of the other surfaces. The conductive paths are oriented such that, for each of the surfaces, macroscopic current flows, with respect to the surfaces, in a direction other than the direction in which microscopic current flows in the paths.

Abstract: The invention relates to a resonator structure comprising a printed board of an insulating material; a helix resonator mounted on the printed board, the helix resonator being formed by a wire wound into a cylindrical coil with a number of turns, one of the turns comprising a straight portion bent in parallel with the surface of the printed board; and a casing surrounding the helix resonator and having at least an inner and outer surface made of an electrically conductive material. In order to improve the reproduction fidelity of the matching of the helix resonator in series production, the resonator structure according to the invention is characterized in that a micro strip conductor is provided on the surface of the printed board, the microstrip being electrically connected to a predetermined position on said straight portion.

Abstract: A multicoupler for use in interfacing multiple frequency-agile transceivers to a single antenna. The multicoupler includes a set of high-Q filters and a switching matrix for selectively connecting the transceivers to the filters. The filters have frequency shift capabilities so that a broad frequency range can be covered by a limited number of filter units. The switching matrix is adapted for connecting any one of the transceivers to any one of the filters in accordance with the operative frequencies of the transceivers and filters. The structure of the multicoupler enables it to rapidly track frequency hopping patterns executed by the transceivers while providing good isolation between the transceivers and producing limited amounts of intermodulation distortion.

Abstract: A stripline structure has a stabilized resonant frequency against temperature variations. It includes a lower and an upper substrate of ceramic materials, each substrate having opposing inner and outer surfaces. Each of the outer surfaces are covered with a layer of conductive material constituting ground planes. Resonator strips of conductive material are situated on each of the inner surfaces, and each have one end connected to the ground, while the opposite end is an open circuit. The upper and lower substrates are bonded together along the length of their respective resonator strips, thereby producing the stripline structure. The length of the resonator determines the resonant frequency of the stripline structure. The two substrates are made of materials having opposite dielectric temperature coefficient.

Abstract: Inductance coupling type transmission channel couplers mounted on either side of an insulator such as window glass of a vehicle including a pair of resonator, each including a cylindrical outer conductor and a helical conductor coaxially provided in the outer conductor with one end connected thereto. The resonant frequency of the tuning inductance circuit thus constructed is set at 1/3 of an objective frequency, and the ratio between the inner diameter and the outer diameter of the helical conductor is set at 1.1-2.0.

Abstract: There is provided a probe to detect a nuclear magnetic resonance signal in which each of a plurality of arms forming a current path of an Alderman-Grant type coil is divided into two conductor plates, the two conductor plates are connected by an inductor, and a resonance frequency is reduced by increasing the inductance of the current path.

Abstract: An arrangement for a superconducting resonator suitable for use in electronic filters is disclosed, in which a resonator exhibits an increased amount of internal inductance without a lengthening of the resonator. By utilizing a relatively thin dielectric material, a significant amount of magnetic field is made to exist in a layer of the superconductors nearest to the dielectric. This magnetic field induces a non-negligible internal inductance within the layer. The net result of having this extra inductance is that the wave velocity is no longer a constant, independent of dielectric thickness. Thus the resonator can be constructed to be significantly shorter than the conventional wave velocity equation would imply. Hence, the present invention provides a reduction in the length as well as in the cross-sectional area of a resonator, which means that one or more of such resonators may then be advantageously utilized to achieve significantly reduced filter size.

Abstract: A multiply tuned bird cage results from the combination of low pass and high pass filter elements to yield a band reject network behaving as a low pass network at a low frequency and a high pass network at a high frequency. A band pass bird cage coil is obtained by adding a parallel LC combination to each leg of a bird cage coil to create additional poles in the impedance curve z(f).

Abstract: An RF transformer employs at least three elongated conductive elements in generally parallel spaced relationship. At least a first inductive element is connected between a pair of the conductive elements to provide a desired field distribution. A diagnostic technique for determining the frequency shift of the transformer employs a perturbing object which is selectively longitudinally positioned within the transformer. The transformer has particular utility as an RF excited gas laser.

Abstract: A surface coil arrangement for magnetic resonance data acquisition comprising a first coil designed to generate a circular magnetic field and a second coil designed to generate a linear magnetic field in quadrature to said circular magnetic field with said first and second coils positioned relative to one another to provide circular polarization.

Abstract: A high-frequency coil of the type of slot resonator in which outer conductors that have wing portions at both ends thereof and that are divided, are formed on the cylindrical surface, and ring-like inner conductors are formed on the inside of the wing portions. The wing portions have a width different from the width of the inner conductors. The self resonance frequency of the coil is adjusted by adjusting the width which is smaller than the other width. Further, the neighboring tips of the wing portions are opposed to each other via an air gap. The self resonance frequency is also adjusted depending upon the position of the dielectric plate inserted in the gap.

Abstract: The structure includes a conductive path and a ground plane applied to opposite faces of an insulating support. The ground plane has parallel slots placed under the conductive path and transversely thereto.

Abstract: A surface resonator for use in nuclear magnetic resonance tomography is a single turn loop of ribbon-like electrical conductor having spaced ends facing each other which form a capacitor whose capacitance determines the resonant frequency. The loop of ribbon-like conductor is shaped to conform substantially to the generated surface of a truncated cone. The ends of the loop may be in the form of spaced plates for providing the necessary capacitance, or may be connected by one or more discrete component capacitors.

Abstract: A radio frequency coil for nuclear magnetic resonance imaging comprises two annular conductors which are coaxially disposed at opposite ends of a prescribed axis and at least one pair of longitudinal conductor groups which are symmetrically disposed in parallel to the prescribed axis and extend longitudinally from one annular conductor to the other. Each longitudinal conductor group comprises a plurality of longitudinally-extending electrical conductors whose ends are secured and electrically connected to the annular conductors. The longitudinal conductors are preferably in the form of electrically conducting wires, tubes, or plates. The annular conductors can be in the form of one-piece rings or in the form of one or more pairs of arcuate plates which are electrically connected with one another and disposed about the prescribed axis in the form of a ring.

Abstract: An NMR probe comprises a pair of capacitively coupled inductive members forming a first circuit resonant to a relatively high rf signal and also forming a portion of a second tuned circuit resonant at a relatively low rf signal, the entire circuit balanced to define a virtual ground in said circuit portions and relative isolation of low and high frequency sources achieved with transmission line elements.

Abstract: A quadrature probe for nuclear magnetic resonance includes two sets of coils which are combined with an angle of 90.degree. therebetween. Four pieces of outer conductors and two pieces of ring-shaped inner conductors are capacitively coupled to each other through an insulator or an air gap. In the outer conductor(s) in at least one of a set of outer conductors disposed at positions symmetrical with respect to each other so as to form a first coil and a set of outer conductors disposed at positions symmetrical with respect to each other so as to form a second coil, a conductor member(s) for adjustment is attached in parallel to the arm portion(s) in that outer conductor(s) of that set. Alternatively, the arm portion(s) itself in that set is slidably attached to the wing portions in that set.

Abstract: A resonator for microwave or VHF-UHF bands has a ring dielectric plate, one surface of which is metalized to make a resonant line, and at least one of other surfaces of which is also metalized to make a grounded or earth conductor. The resonator is very small in size and has a large unloaded Q value. Several embodiments are disclosed.

Abstract: An RF transformer employs at least three elongated conductive elements in generally parallel spaced relationship. At least a first inductive element is connected between a pair of the conductive elements to provide a desired field distribution. A diagnostic technique for determining the frequency shift of the transformer employs a perturbing object which is selectively longitudinally positioned within the transformer. The transformer has particular utility as an RF excited gas laser.

Abstract: A device for converting DC to RF has a monolithic PIN diode adapted to be coupled to a DC supply. The diode receives light switching pulses and is coupled to a monolithic resonator. The monolithic form provides compactness and reliability, while the diode, which is reversed biased when OFF, prevents substrate leakage currents. The diode and the resonator can be made in a single substrate, e.g., silicon, or in different substrates, e.g., silicon for the diode to obtain a long carrier lifetime and, thus, minimize the light pulse repetition rate, and GaAs for the resonator to obtain a high Q. The resonator can also act as an impedance transformer.

Abstract: A microwave diode tuning circuit including am IMPATT diode holder of coaxial form and an adjustable capacitor connected in a parallel resonant circuit by microstrip transmission line. The tuning circuit includes a stabilization network and a bias insertion network. Optionally, the tuning circuit may include a hybrid junction for coupling two such diode tuning circuits together. the diode holder includes an internally-externally threaded sleeve providing means for continuously adjusting, through a limited range, the inductance of the resonant circuit.