Abstract: A frequency conversion system with improved performance. In one embodiment an image reject mixer is used to perform frequency conversion providing an initial degree of suppression of the image and local oscillator leakage signals, and a signal to noise enhancer (SNE) is used to further suppress the image and local oscillator signals, the signal to noise enhancer being a nonlinear passive device that attenuates low-power signals while transmitting high power signals with little loss. The signal to noise enhancer may be fabricated as a thin film of yttrium iron garnet (YIG) epitaxially grown on a gadolinium gallium garnet (GGG) substrate, the GGG substrate secured to a microwave transmission line from the input to the output of the signal to noise enhancer, such that the thin film of yttrium iron garnet is close to the transmission line.

Abstract: A frequency conversion system with improved performance. In one embodiment an image reject mixer is used to perform frequency conversion providing an initial degree of suppression of the image and local oscillator leakage signals, and a signal to noise enhancer (SNE) is used to further suppress the image and local oscillator signals, the signal to noise enhancer being a nonlinear passive device that attenuates low-power signals while transmitting high power signals with little loss. The signal to noise enhancer may be fabricated as a thin film of yttrium iron garnet (YIG) epitaxially grown on a gadolinium gallium garnet (GGG) substrate, the GGG substrate secured to a microwave transmission line from the input to the output of the signal to noise enhancer, such that the thin film of yttrium iron garnet is close to the transmission line.

Abstract: The cartridge 10 provides an inexpensive, effective, clean, reliable means of supplying pressurized cleaning fluid for two component applicators 14. The low friction piston 18 design reduces drag and provides consistent cleaning fluid 12 pressure.

Abstract: A magnetostrictive-based sensor is disclosed which obtains higher return signals through the use of multiple consecutive input pulses

Abstract: A waveguide driving circuit for generating a current pulse in a waveguide includes a voltage source for providing a direct voltage, a choke the first terminal of which is coupled to a first terminal of the voltage source, a first switch the first terminal of which is coupled to a second terminal of the choke and the second terminal of which is coupled to a second terminal of the voltage source, the waveguide the first terminal of which at a first waveguide end is coupled to the first terminal of the first switch and the second terminal of which at the first waveguide end is coupled to a second terminal of the voltage source, and a controller implemented to open and close the first switch, to generate a current pulse at the terminals of the waveguide at the first waveguide end.

Abstract: An apparatus and method for measuring the position of a member. The apparatus has a sonic waveguide, a generator for generating an interrogation sonic wave at a first position in the sonic wave guide, and a transducer for converting the interrogation sonic wave, at a second position in the sonic wave guide, to an interrogation signal. A timer can be enabled in response to the generator generating the interrogation sonic wave and stopped in response to the transducer converting the interrogation sonic wave so as to determine the propagation time delay of the interrogation sonic wave and the distance between the first and second positions. When the transducer is attached to a member, the position of the member can be determined from this distance. The apparatus can include a transmitter for transmitting the interrogation signal. The generator can be configured to generate an excitation sonic wave which is converted by the transducer to a power signal for powering the transmitter.

Abstract: Generation, coding and transmission of an effective video form, scalable portrait video. As an expansion to bi-level video, portrait video is composed of more gray levels, and therefore possesses higher visual quality while it maintains a low bit rate and low computational costs. Portrait video is a scalable video in that each video with a higher level always contains all the information of the video with a lower level. The bandwidths of 2-4 level portrait videos fit into the bandwidth range of 20-40 Kbps that GPRS and CDMA 1X can stably provide. Therefore, portrait video is very promising for video broadcast and communication on 2.5 G wireless networks. With portrait video technology, this system and method is the first to enable two-way video conferencing on Pocket PCs and Handheld PCs.

Abstract: A magnetostrictive level sensing instrument is used for sensing level in a process vessel and comprises an elongate tube having a near end and a distal end. A magnet is selectively positionable proximate the tube responsive to level of the processed material. A magnetostrictive wire in the tube has first and second ends. The second end is operatively secured at the tube distal end. A pair of shear mode crystals are mounted proximate the tube near end. The crystals sandwich the magnetostrictive wire proximate the first end. A sensing circuit is operatively connected to the magnetostrictive wire and the pair of crystals for generating an electrical pulse on the magnetostrictive wire whereby a magnetic field produced by the magnet interacts with the electrical pulse to produce a torsional wave on the magnetostrictive wire sensed by the pair of crystals.

Abstract: A magnetostrictive-based sensor is disclosed which obtains higher return signals through the use of multiple consecutive input pulses.

Abstract: A magnetostrictive system is shown wherein there is included a wave guide but no return wire. The wave guide is folded and acts as the completed wire (whether solid or hollow) for conducting current for the current input pulse.

Abstract: A high power ferrite microwave phase shifter that is both compact and low cost. The ferrite phase shifter includes a waveguide having a first cylinder and a second cylinder, the radius of the second cylinder being less than the radius of the first cylinder. The second cylinder is disposed within the first cylinder such that the two cylinders have a common axis of symmetry. The waveguide includes a first septum formed as a disk and disposed within the second cylinder. The disk has a pie-shaped aperture formed therethrough and is centrally disposed within the second cylinder so that the two cylinders and the disk share the same axis of symmetry. The second cylinder has an opening formed therethrough that is aligned with the pie-shaped aperture. The waveguide further includes a second septum that extends from the first cylinder to the disk center while bisecting the pie-shaped aperture, thereby separating an input from an output of the ferrite phase shifter.

Abstract: A magnetostatic wave filter that includes a ferromagnetic substance stacked on one side of a dielectric substrate, one side of which is grounded, and the filter includes an input section having an input transfer line and an input energy transformer for causing the energy transformation between an electromagnetic wave and a magnetostatic wave, and an output section having an output energy transformer for causing the energy transformation between the electromagnetic wave and the magnetostatic wave and an output transfer line. The width of exciting lines in the input energy transformer and the output energy transformer varies in a longitudinal direction, the filter includes a shield film formed of a grounded conductive film having holes through which a magnetic thin film can pass between the input section and said output section, to prevent coupling of an electromagnetic wave.

Abstract: Magnetostatic devices includes: input and output electrodes for including energy conversion pattern provided in a dielectric substrate; a multi-layer -magnetic substance structure placed at an upper portion of the dielectric substrate, wherein magnetically active thin film is placed at both sides of a magnetically inactive substrate; an upper shield, composed of grounded conductor, for preventing the input and output electrodes from coupling; a lower shield provided at the dielectric substrate, wherein the substrate contain a hole with the same length as the upper shield, and walls of said hole are provided with conductor; a magnetostatic wave end portion, inserted into the dielectric substrate to be placed at both end plane of the multi-layer magnetic structure, for blocking the magnetostatic wave not to reflect therefrom; and a magnetostatic wave reflector, provided in the dielectric substrate as a line whose width vary, for reflecting and selecting a desired pass band before it reaches to the magnetostatic

Abstract: In accordance with the invention, magnetostrictive saw devices are provided with improved transducer structures for enhanced performance. In one improved device, the transducers are in the form of gratings with interconnected ends for reduced resistance and inductance. In another embodiment, the transducers are shaped to provide apodization. In yet a third embodiment, transducer performance is enhanced by patterning composite structures.

Abstract: A magnetostatic wave device comprises a magnetic garnet single crystal film. The single crystal film magnetic garnet is represented by the general formula of Y3Fe5-x-yInxMyO12 (wherein M is at least one of Ga, Al and Sc, 0.01≦x≦0.45 and 0≦y≦1.2) and the Curie temperature is about 150° C. to 285° C.

Abstract: A magnetostatic-wave device includes a dielectric substrate on which parallel first electrically conductive lines are formed. A magnetostatic-wave device formed of a gadolinium-gallium-garnet (GGG) substrate on which yttrium-iron-garnet (YIG) thin films are formed is disposed on the first electrically conductive lines. Crossed second electrically conductive lines are formed on a YIG thin film. Lands are formed at both ends of these electrically conductive lines and are connected to each other with bonding wire to form one electrically conductive line. Input and output ends are formed between both ends of this electrically conductive line and the ground.

Abstract: There is provided a magnetostatic wave device which operates even with a substitution R, A:YIG having a small film thickness and which has a wider operational frequency band. A magnetostatic wave device comprising a magnetic garnet film is provided which is made of a material expressed by a general formula: (Y.sub.1-r R.sub.r).sub.3 (Fe.sub.1-a A.sub.a).sub.5 O.sub.12 where R is at least one selected from among La, Bi, Gd and Lu; A is at least one selected from among Al, Ga, In and Sc; r and a are within the ranges 0.ltoreq.r.ltoreq.1 and 0.ltoreq.a<1, respectively; and r and a can not be zero at the same time. Further, the crystal structure of said magnetic garnet film is a superlattice.

Abstract: A magnetostrictive waveguide position measuring apparatus includes a waveguide extending between opposed anchored ends. A magnet is displaceable along the waveguide and generates torsional strain in the waveguide in response to an electrical excitation signal transmitted along the waveguide. A piezoceramic element sensor is coupled to the waveguide to sense the torsional strain signal on the waveguide. A signal processor determines the relative elapsed time between the excitation signal and the output signal of the piezoceramic element to determine the position of the magnet along the waveguide. The sensor is coupled to the waveguide by a low resonance coupling medium.

Abstract: Array sensors are described which are based on the magnetostrictive delay line technique, where sensing is based on the modification of the magnetic circuit along the magnetostrictive delay line. The proposed array sensors can perform a quantitative measurement of signals instead of the merely sensing activity performed by sensors of the prior art. Further advantageous characteristics of the proposed array sensors is that magnetoresistive devices and alternatively a detecting magnetostrictive delay line with two detecting coils at the ends thereof are used at the output of the sensor array, and that the detected pulsed width T is monitored instead of the peak voltage, this offering an improved response of the proposed array sensors. The above improvements are used in various applications and specifically are proposed novel digitizers and displacement sensors as well as a magnetic field distribution sensor.

Abstract: A magnetostrictive waveguide type position measuring system wherein the wire waveguide is mounted within a small diameter brass tube which, in turn, is mounted by way of resilient suspension components within a rigid outer tube affixed to a position reference frame. The resilient components isolate the waveguide from relatively high frequency shock inputs characteristic of rough environment applications. The waveguide is made of rolled and drawn wire with a round section, but the terminal ends are gradually reconfigured from round to flat, rectangular sections and are sandwiched between acoustic dampening pads to reduce or eliminate sonic reflections.

Abstract: A surface magnetostatic wave device includes an Fe-containing garnet single crystal film grown on a gadolinium gallium garnet substrate. The crystallographic plane azimuth of the gadolinium gallium garnet substrate can be one of a (110) plane, a (100) plane, and a (211) plane. The device achieves both a reduced saturation magnetization and a reduced anisotropic magnetic field to thereby minimize the lowest frequency in the propagation band.

Abstract: A length measuring apparatus that uses an ultrasonic magnetostrictive delay line can detect a position with high accuracy by utilizing a reflected wave positively. In a measuring apparatus using an ultrasonic magnetostrictive delay line in which a wave transmitter (4) is disposed at one end of an ultrasonic magnetostrictive delay line (1), and the other end of the ultrasonic magnetostrictive delay line (1) is made an open end, a detecting coil (3) is wound around the outer periphery of the ultrasonic magnetostrictive delay line (1) over the whole area of the measuring range, a magnet piece (2) is disposed so as to become slidable along the ultrasonic magnetostrictive delay line (1) an a position of the magnet piece (2) is measured on the basis of a delay time of a detection pulse (B) produced in the detection coil (3) relative to a drive pulse (A) applied to the wave transmitter (4), a period (T.sub.

Abstract: A damping element for use with a waveguide that supports a current pulse and results in a torsional or longitudinal strain wave is disclosed. The damping element is to dampen the reflection of the strain wave and includes a sleeve surrounding the waveguide and a mechanism for applying pressure on the sleeve so the sleeve exerts pressure on the waveguide, thereby gradually dampening the strain wave energy along the length of the waveguide surrounded by the damping element sleeve to prevent reflection of the strain wave.

Abstract: An improved magnetostrictive wire based position transducer that has applications in both liquid level measuring systems and in position indicating systems. A cylindrically structured and circularly polarized piezoelectric element directly measures the torsional acoustic waves in the magnetostrictive wire as they are received by the sensor. The cylindrical structure of the sensor eliminates many of the inadvertently detected acoustic and electrical pulses within the wire that are not indicative of the passage of the torsional wave of concern. The present system provides an improved sensor configuration which is selectively sensitive to torsional waves while being insensitive to vibrations in alternate planes. This improved piezoelectric sensor in combination with the electrical configuration allows placement of the magnetostrictive wire apart from the liquid whose level is being measured or from the indicator whose position is of concern.

Abstract: The present application discloses a magnetostrictive linear displacement detector with an axial coil torsional strain transducer. The displacement detector includes a magnetostrictive wire, a return wire and a magnet disposed for displacement along the magnetostrictive wire. A torsional strain sensor at the head end generates an electrical indication of the torsional strain within the magnetostrictive wire induced by passage of an electrical excitation by the position of the magnet. The torsional strain sensor includes two serially connected coils wound in opposite directions. The total length is short compared with the rate of electrical propagation within the magnetostrictive wire and long compared with the rate of torsional strain propagation within the magnetostrictive wire. The induced current within the two coils from electrical excitation of the magnetostrictive wire substantially cancel out because generally the whole sensor is excited simultaneously.

Abstract: A magnetostatic wave (MSW) signal-to-noise (S/N) enhancer includes a divider for dividing an input signal into a first and a second path signals, first and second microwave-MSW transducers for transducing the first and second path signals into the first and second path transduced signals, and a combiner for combining the first and second path transduced signals in opposite phase to each other. The first path signal contains a desired signal which is higher than a first saturation level and a noise component which is lower than the first path threshold power level. The first microwave-MSW transducer outputs the noise in linear operation and the desired signal in saturation operation. All the component signals of the second path signal including noise are lower than the second path threshold power level and are output in a linear operation by the second microwave-MSW transducer.

Abstract: A proposal is made for a magnetostatic-wave chip capable of treating a relatively large electric power even when the size of the magnetostatic-wave device, such as filters, delay lines, resonators and oscillators, constructed therewith is very small. The chip is prepared by the epitaxial growth of a rare earth-iron garnet film on the substrate surface and the desired performance of the device can be achieved when the parameters of .DELTA.H/4.pi.Ms,.DELTA.H being the half-value width of the magnetic rosonance peak at 9.2 GHz and 4.pi.Ms being the saturation magnetization, and the volume of the magnetostatic-wave film of the chip fall within the area defined by the five points P1 to P5 shown in FIG. 1.

Abstract: A magnetic sight gage sensor comprises a sensor for determining the liquid level in a process vessel utilizing a magnetic float on the interior of a tube. The tube is connected at different levels to a process vessel and contains a liquid that is maintained at the same level as the liquid inside the process vessel. A magnetostrictive displacement transducer is coupled to the tube or sight glass on the exterior of such glass, so it is out of the process fluid. The transducer provides signals indicating the position of the float relative to a reference position on the transducer. The tube or sight glass is made of a non-magnetic material in order to allow transmission of the magnetic field from the float to the transducer.

Abstract: A force transducer which uses current pulses in a conductor to generate acoustic pulses in a magnetostrictive delay line. The pulses are sensed by a coil around the line. The magnitude of the pulses is modified by force applied to the transducer by changing the shielding effect of a magnetoelastic ribbon (between the conductor and the delay line) by applying a force to be sensed thereto. The transducers are economic and easily assembled into arrays for sensing stress distribution in two dimensions because the common conductors can be used for the columns of the array and common delay lines can be used for the array rows. Each column then has a common current-pulse generator and each row has a common detector coil. A similar technique may be used for sensing the spatial distribution of other parameters such as temperature, magnetic field or displacement.

Abstract: The present invention is a combined magnetostrictive linear displacement detector and plural location temperature detector. The combined apparatus produces a composite signal for transmission on a 2 wire transmission line. The resistances of the temperature sensitive resistors as well as two reference resistors are measured in a predetermined sequence. The linear displacement is measured by the length of time required for a torsional strain to travel along the magnetostrictive wire to the position of the magnet. A pulse generator generates a predetermined number of pulses for each resistance measurement having pulse period corresponding to the measured resistance, with the minimum such pulse period preferably being greater than twice the maximum time required for a torsional strain to propagate the length of the magnetostrictive wire. An electrical signal is supplied to the transmission line when either said pulse generator generates a pulse or the induced electrical signal is detected.

Abstract: A magnetostrictive linear position transducer including a position indicating magnet. Magnet position information is fed back to the detector to automatically control the detector threshold as a function of magnet position.

Abstract: A magnetostrictive linear displacement detector with increased position resolution includes a magnetostrictive wire anchored at opposite head and foot ends with a reflection termination at the foot end and a damping termination at the head end. A return wire is connected to the foot end of the magnetostrictive wire. The magnetostrictive wire is electrically excited at its head end. A variable position to be detected is represented by a magnet disposed for displacement along the magnetostrictive wire. A torsional motion sensor at the head end generates an electrical indication of the torsional motion within the magnetostrictive wire induced by passage of the electrical excitation by the position of the magnet. The displacement is determined from the interval of time between the detection of the torsional motion traveling directly from the magnet and the detection of the torsional motion reflected from the reflection termination.

Abstract: A damping device for damping mechanical vibrations in a small diameter elongated member, such as a waveguide carrying torsional strain waves, includes a damping material contained inside a housing on the waveguide, the damping material is a viscous liquid that does not evaporate or change viscosity over a wide temperature range and which has additives for providing adequate mass density for damping vibrations in such elongated member. The use of a viscous liquid and additives for changing the mass density permits varying the mass density to match impedances and reduce the amplitudes of any reflective waves. The viscous liquid preferably comprises a silicone base oil partially filled with zinc oxide and metal particles to give the characteristic of stable viscosity across a wide range of temperature and provide the necessary attenuation while obtaining good coupling of the damping material to the elongated member.

Abstract: A displacement transducer utilizes a torsional strain waveguide having a magnetic member that is adjustable positioned along the length of the waveguide, when an electrical current pulse is passed along the waveguide and reaches the magnet torsional strain wave is created in the waveguide. The torsional strain wave will be reflected back toward a mounting end of the waveguide where a converter or sensor is positioned to sense the strain wave signal and convert it to an electrical output signal. The strain wave signals have signal lobes of a time period. A waveguide mounting block supports the waveguide at the mounting end and provides a reflection point for the torsional strain waves. The waveguide mounting block is on an opposite side of the signal sensor from the magnet.

Abstract: A liquid level detector of the type in which a magnetostrictive wire extends through the liquid level measurement range and is captured in a tensioned vertical orientation within a stainless steel tube. Liquid level is measured as a function of the time required for a torsional disturbance imparted the wire near the top to travel along the wire to a magnet which is contained within a liquid level float which slides up and down along the tube. The torsional disturbances imparted to the wire by means of a piezoelectric crystal to which the wire is easily clamped. Accuracy is enhanced by measuring liquid level as a function of the elapsed time between an actuation signal and the first zero crossing of the voltage which is induced as the torsional strain passes through the area of influence of the sliding magnet.

Abstract: A sonic delay line assembly suitable for shipping in coiled form allowing for expedited installation, particularly in liquid storage tanks. The sonic delay line comprises a sonic waveguide made of solid wire, which also serves as an electrical pulse conductor for the generation of sonic pulses on waveguide through interaction with a positionable static magnetic field. A sonic waveguide containment can be provided to protect the flexible tubing and sonic waveguide. Positioned around the containment and free to ride up and down the containment as liquid levels in the tank vary is a float. The float carries an annular magnet with poles axially aligned with sonic waveguide to provide the magnetic field with which the magnetic fields of the electrical pulses on the sonic waveguide interact.

Abstract: A force transducer is described which uses current pulses in a conductor to generate acoustic pulses in a magnetostrictive delay line. The pulses are sensed by a coil around the line. The magnitude of the pulses is modified by force applied to the transducer either by changing the shielding effect of a magnetoelastic ribbon (between the conductor and the delay line) by applying a force to be sensed thereto, or in another alternative by modifying the distance between the conductor and the delay line in accordance with applied force. The transducers are economic and easily assembled into arrays for sensing stress distribution in two dimensions because the common conductors can be used for the columns of the array and common delay lines can be used for the array rows. Each column then has a common current-pulse generator and each row has a common detector coil. A similar technique may be used for sensing the spatial distribution of other parameters such as temperature, magnetic field or displacement.

Abstract: A wide band large dynamic range current sensor operable to measure current leakage in an external conductor utilizing a magnetostatic spin wave delay line (MSW) device is described. The measurable changes in well known electromagnetic properties of ferrite films, as utilized in MSW devices when these films are exposed to external current induced magnetic fields, results in a current sensitive detection device. A method of current detection using this device is also described. Specific, low power microelectronic applications as well as, high power, local and remote current detecting embodiments are included.

Abstract: A phased array radar antenna utilizing signal time delay magnetostatic spin wave devices operable to provide feed line transmit time control for variable length transmission feed lines. The preferred embodiment of an improved phased array radar antenna incorporates ferrite devices controlled by d.c. voltage driven ferroelectrics.

Abstract: A liquid level detector of the type in which a magnetostrictive wire extends through the liquid level measurement range and is captured in a tensioned vertical orientation within a stainless steel tube. Liquid level is measured as a function of the time required for a torsional disturbance imparted the wire near the top to travel along the wire to a magnet which is contained within a liquid level float which slides up and down along the tube. The torsional disturbances imparted to the wire by means of a piezoelectric crystal to which the wire is easily clamped. Accuracy is enhanced by measuring liquid level as a function of the elapsed time between an actuation signal and the first zero crossing of the voltage which is induced as the torsional strain passes through the area of influence of the sliding magnet.

Abstract: A mode converter for a distance measuring device having a sonic delay line with a permanent magnet movable along same, the converter having a free-standing magnetostrictive armature with one end attached to the delay line and the other end terminating dampinglessly within the usual coil. The armature length and shape are such that the longitudinal stress wave initiated by an electrical pulse in the coil strengthens the mechanical pulse applied to the delay line.

Abstract: A metallic glass ribbon of the formulaFe.sub.w B.sub.x Si.sub.y C.sub.zwherein0.78.ltoreq.w.ltoreq.0.83,0.13.ltoreq.x.ltoreq.0.17,0.03.ltoreq.y.ltoreq.0.07,0.005.ltoreq.z.ltoreq.0.03,andw+x+y+z=1,is annealed to remove mechanical strains and exposed to a magnetic field in the plane of the ribbon and transverse to the long axis of the ribbon. The resulting metalic glass ribbons have very large magnetic coupling coefficients (k.sub.33 >0.9). The treated ribbons are useful in magnetostrictive transducers and in passive listening devices such as hydrophones or pressure sensors.

Abstract: An automatic position coordinate determining device comprises a data tablet which has a single magnetostrictive element in which strain waves are induced for determining the position coordinates of a pointer relative to a pair of mutually orthogonal coordinate axes obliquely disposed with respect to the magnetostrictive element. Two mutually orthogonal pluralities of parallel equidistantly spaced electrical conductors form a grid network on the top surface of the tablet. These pluralities of conductors are wrapped around the edge of the tablet and spatially compressed to form respective X and Y conductor grids over opposing quadrants of the tablet bottom surface. A movable pointer travels along the top surface of the tablet while the magnetostrictive element is arranged along the diagonal of the tablet bottom surface. The conductors of the X and Y grids are inductively coupled to the diagonal magnetostrictive element.

Abstract: A magnetostatic wave device unit in which the magnetic biasing unit includes a carrier member which contains one of the pole pieces and forms an enlarged mechanical and electrical support surface for a magnetostatic wave device.

Abstract: The invention relates to an ultrasonic distance measuring device for linear distance measurement comprising a tube of magnetostrictive material, a magnet displaceable relative to the tube for generating torsional ultrasonic pulses as a function of electrical pulses produced by a pulse generator and travelling along the tube, these torsional ultrasonic pulses serving as position signals, and also comprising an ultrasonic receiver coupled to the tube for converting ultrasonic pulses generated in the tube into electrical signals and a measuring circuit for ascertaining the position of the movable magent as a function of the time interval between the signals obtained from the position signals and at least one respective reference signal generated by the presence of an electrical pulse.

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 cascade combination of magnetostatic delay line elements operating in different signal propagation modes for the purpose of achieving dispersion cancellation; magnetic bias control of the attained frequency-dependent delay and a magnetic bias field establishing apparatus for providing the tubular, laminar magnetic flux needed for backward volume wave operation of a magnetostatic delay element are also included.

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: A position determining device has two perpendicular longitudinal magnetostrictive elements. A grid of a plurality of closed loop conductors has two parallel straight legs which form the grid. A flux producing element inductively coupled to at least one of said grid conductors causes an electrical current in that conductor. In turn that current induces a strain wave in the magnetostrictive element. Near the end of the magnetostrictive element is a sensing means to detect the strain wave comprising a lumped inductive capacitive delay line substantially having a plurality of evenly spaced inductive coils aligned with the magnetostrictive elements.The lumped delay line is defined by the formulas ##EQU1## where w is the overall length of the delay line; L is the total inductance, C is the total capacitance, Z is the terminating impedance, c is capacitance of the capacitance associated with each coil, and n is the number of coils.

Abstract: A magnetostatic wave device which has broad application in the signal processing arena is disclosed herein. Basically, the magnetostatic wave device includes a layer of magnetized magnetic medium having a surface which includes a prespecified area to support the propagation of magnetostatic waves. A generator element is disposed at one end of the propagation area and is operative to carry an electromagnetic signal to generate magnetostatic waves supported by the propagation area. A pattern of conductive material having a plurality of conductive paths commonly coupled together at both ends is disposed in juxtaposition with the propagation area of the magnetic medium surface. In one embodiment, the conductive pattern includes a variable impedance coupled to each of a desired number of the conductive paths thereof to vary the impedance of the path. Each variable impedance is adjustable controlled in accordance with an applied governing signal.