Abstract: A lumped element frequency selective limiter device and corresponding method for the design is provided, including a variety of LE-FSL device structures and systems. The devices can utilize ferrite-based materials in a lumped element inductor operable at and above 1 GHz. The methods and systems can utilize devices having cascaded configurations of lumped elements to improve operating performance the devices.

Abstract: A bulk acoustic resonator assembly and methods for fabricated the resonator assembly is provided. The resonator includes a cavity on a first surface of a substrate, with a sheet of low acoustic loss material suspended over the cavity. The sheet of low acoustic loss material is configured such that an associated fundamental frequency of the sheet of low acoustic loss material is a function of a length of the sheet of low acoustic loss material in a direction parallel to the first surface of the substrate. A transducer includes an electromechanical layer on the sheet of low acoustic loss material and a patterned conductive material formed on the electromechanical material. The transducer is configured to induce vibrations in the low acoustic loss material upon application of an electrical signal to the conductive pattern.

Abstract: Multi-function receivers are disclosed in which high dynamic range active microwave filters using nanoscale devices are disposed within a switched channelizer stage. In an embodiment the receiver includes an input low noise amplifier, a switched channelizer comprised of active filters utilizing nanoscale devices, an output amplifier, a mixer, and an analog to digital converter. Additionally, the use of highly selective active filters in the channelizer allows for the optional elimination of the mixing stage, improving cost and overall volume.

Abstract: Multi-function receivers are disclosed in which high dynamic range active microwave filters using nanoscale devices are disposed within a switched channelizer stage. In an embodiment the receiver includes an input low noise amplifier, a switched channelizer comprised of active filters utilizing nanoscale devices, an output amplifier, a mixer, and an analog to digital converter. Additionally, the use of highly selective active filters in the channelizer allows for the optional elimination of the mixing stage, improving cost and overall volume.

Abstract: A bulk acoustic resonator assembly and methods for fabricated the resonator assembly is provided. The resonator includes a cavity on a first surface of a substrate, with a sheet of low acoustic loss material suspended over the cavity. The sheet of low acoustic loss material is configured such that an associated fundamental frequency of the sheet of low acoustic loss material is a function of a length of the sheet of low acoustic loss material in a direction parallel to the first surface of the substrate. A transducer includes an electromechanical layer on the sheet of low acoustic loss material and a patterned conductive material formed on the electromechanical material. The transducer is configured to induce vibrations in the low acoustic loss material upon application of an electrical signal to the conductive pattern.

Abstract: Methods of producing polycrystalline and single crystal dielectrics are disclosed, including dielectrics comprising CaCu3Ti4O12 or La3Ga5SiO4. Superior single crystals are manufactured with improved crystallinity by atomic lattice constant adjustments to the dielectric and to the substrate on which it is grown. Dielectric materials made according to the disclosed methods are useful for manufacture of energy storage devices, e.g. capacitors.

Abstract: Methods of producing polycrystalline and single crystal dielectrics are disclosed, including dielectrics comprising CaCu3Ti4O12 or La3Ga5SiO4. Superior single crystals are manufactured with improved crystallinity by atomic lattice constant adjustments to the dielectric and to the substrate on which it is grown. Dielectric materials made according to the disclosed methods are useful for manufacture of energy storage devices, e.g. capacitors.

Abstract: A narrow bandwidth (1 to >100 MHz) HTS microwave filter (30 or 50) is described which is tunable over a moderate frequency range (100 to >1000 MHz at X-band). The low loss (<1 dB) and GHz/microsecond tuning rates enable the filter to operate as a radar preselector filter. The filter consists of a multi-pole microstrip or stripline HTS coupled one-half resonator pattern deposited onto a ferrite substrate (32 or 52, 54). The ferrite substrate is operated in a latching mode like that in the operation of digital phase shifters. The filter tunability arises from the variation of the effective permeability with the remanent magnetization.

Abstract: A planar phase shifter formed of multiple layers of a ferrite. Selected layers of the ferrite are patterned with a conductor and the multiple layers of magnetic dielectric and conductor are cofired. The phase shifter is fabricated by first obtaining ferrite powder. Then, layers of the ferrite are made, preferably by tape casting. Next the ferrite layers are metallized by applying selected amounts of conductive metals in a selected pattern upon the tape. Selected numbers of vias are placed through selected layers of tape and conductive metal is placed in the vias to provide vertical connections through the layers. The tape layers are then stacked in a predetermined order and are laminated. The laminated stack of layers is then fired to a temperature of approximately 800.degree. C. to 1000.degree. C., sintering the laminated layers into one integrated structure.

Abstract: This invention is a design for lateral field film bulk acoustic resonators (LF-FBAR). All electrodes in this design are located on one surface of the piezoelectric material, thereby simplifying manufacturing and improving performance. The gap between electrodes is limited to a specified dimension to maximize the efficiency of the device. Single and multi-pole devices are described. Barium magnesium fluoride and lithium niobate are specified as the piezoelectric material for high frequency applications.

Abstract: The invention is directed to an FSL in which a pair of planar ferrite members have planar surfaces in confronting relationship and at least one signal carrying conductor is supported between the ferrites and is closely coupled thereto. A magnetic biasing field is established having field lines disposed at an angle relative to the conductor such that the FSL has an increased attenuation at low frequencies resulting in a relatively flat limiting characteristic across the bandwidth. The conductor may lie in a plane parallel to the field lines or transverse to the field lines. In one embodiment the conductor zigzags in the plane of the field.

Abstract: A frequency selective limiting device is described incorporating a pair of generally planar ferrite members and a plurality of signal-carrying conductors positioned between the ferrite members. The plurality of signal-carrying conductors are located on a single YIG substrate. A D.C. bias field may be generated by a common magnetic source positioned on the surface of the substrate opposite the plurality of signal-carrying conductors.

Abstract: In the present invention magnetostatic wave (MSW) filters of the delay line and resonator type responsive to multimode MSW signals trap a desired MSW mode of the signal and attenuate untrapped modes of the signal in order to provide a higher order band rejection characteristic. In a preferred embodiment a low loss YIG film is disposed on a substrate. An apertured metallization layer on the YIG film defines a region of MSW propagation within the aperture and a metallization layer at the opposite side of the YIG film traps a selected MSW mode in said aperture. A region of high attenuation for MSW waves adjacent the desired propagation region absorbs untrapped MSW waves.

Abstract: A frequency selective limiting device is described incorporating a planar ferrite member and at least one signal-carrying conductor positioned thereon. A conductor is located on the ferrite member to confine a portion of an RF magnetic field produced by the microwave signals within the ferrite member. In one embodiment of the invention, the conductor comprises coplanar ground planes positioned adjacent to the signal-carrying conductor, thereby forming a coplanar waveguide. Alternatively a pair of coplanar conductors may form a slot line. In another embodiment a second ferrite member is positioned in confronting relationship with the first ferrite member carrying the conductors.

Abstract: A plurality of frequency selective limiting (FSL) units are concurrently prepared on a common substrate by depositing a first ferrite member onto a metallized surface of the substrate. The first ferrite member is formed by sputtering a first ferrite film onto the metallized surface and subsequently growing a ferrite layer thereon. A plurality of signal carrying conductors are positioned in spaced relation on the first ferrite member. A second ferrite member is deposited on top in the same manner as the first ferrite member. The overall structure is diced into individual units that are then metallized thereby providing a plurality of FLS's.

Abstract: A frequency selective limiting device is described incorporating a plurality of individual attenuating units spaced apart from one another in substantially parallel relation and positioned between a pair of ground planes. Each individual attenuating unit is interposed between a pair of magnetic strips. In one embodiment of the invention, each individual attenuating unit includes a microstrip conductor positioned between a dielectric substrate layer and a layer of ferrite material. In an alternate embodiment of the invention, each individual attenuating unit includes a microstrip conductor positioned between a pair of planar ferrite members, the pair of ferrite members and microstrip conductor being mechanically supported by a dielectrical substrate layer. In both embodiments of the invention, adjacent attenuating units are serially connected by microstrip jumpers to provide a flow path for microwave signals passed through the limiting device.

Abstract: Electroacoustic resonating apparatus capable of generating resonances of tunable frequencies. The apparatus includes two transducers coupled to a ferrimagnetic substrate at opposite ends thereof. The first transducer converts an input signal into a signal that produces bulk acoustic waves in the ferrimagnetic substrate. The second transducer receives the bulk acoustic waves and converts them into electrical signals, or alternatively a single transducer which performs both input and output functions. Variable magnetizing means located proximate to the ferromagnetic substrate induces a magnetic field throughout the substrate wherein the magnetic field alters the frequencies of the resonance of the acoustic waves. By varying the magnitude of the magnetic field, the frequencies of the resonances may be varied, thereby allowing tuning of the apparatus.

Abstract: An arrangement for improving the frequency plane delay linearity of a frequency dispersive delay line of the type employing ferrite film materials such as yttrium iron garnet. Linearity improvement involves use of frequency selective transducers located at successively different delay locations in the transmitting and receiving areas of the delay line together with ground plane effects and out of phase signal coupling to the transducer elements including exemplary use of a particular type of microwave transmission line for coupling to the magnetic film.

Abstract: A magnetostatic wave device operating within a biasing magnetic field for delaying microwave signals is described including a layer of YIG material having a predetermined thickness, first and second transducers spaced apart for generating and receiving magnetostatic waves in the YIG material and a ground plane having a plurality of spacings from said YIG material, each spacing having a predetermined length along the propagation path between the first and second transducers. The invention further includes first and second layers of YIG material, first and second transducers spaced apart for generating magnetostatic waves in said first material and said first material having a plurality of spacings from said second material, each spacing having a predetermined length along the propagation path from said first to said second transducer. The invention overcomes the problem of undesired phase or group delay variations from a desired linear or quadratic phase variation as a function of frequency.

Abstract: The linearity of group delay versus frequency in magnetostatic wave delay lines is improved by a linear variation of one of three discrete parameters in the region between the two delay line transducers. The parameter variation is applied to magnetostatic wave delay lines that have a ground plane, a magnetic garnet crystal film substrate that is spaced from the ground plane and has transmitting and receiving transducers engaged to it, and a magnetic bias field. The discrete parameters varied are the magnetic bias field; the distance of the substrate from the ground plane; and the thickness of the substrate. Appropriate linear variations of any one of the these parameters provides improved linearity of group delay versus frequency.