Abstract: A structure of a spectrum spreading communication device which solves the problem with the conventional spectrum spreading communication using Barker codes, etc., and limits the rise of the side-lobe of a correctional signal independently of the order of information codes by use of a code sequence having a code length of at least 14. The spectrum spreading communication device uses a pseudo-noise code having code length of at least 14 and a self-correlation side-lobe of not greater than 3 as a pseudo-noise code of a direct spreading communication device which uses the pseudo-noise codes whose polarities are inverted so as to deal with also digital information. Thus, even when the pseudo-noise code length is 14 or more, the side-lobe of the correction coefficient can be restricted. Accordingly, the error rate of the spectrum spreading communication device is reduced and the processing gain is improved.

Abstract: An electroacoustic component including a layer system disposed between two substrates and electroacoustic structures for exciting a guided bulk acoustic wave, the electroacoustic structures being devoid of cavities. The layer system includes a piezo-electric layer, at least one metal layer, and a planarizing layer, which includes a planar interface provided with a substrate disposed directly thereabove. Such a component can be produced at a low cost by direct wafer bonding of two wafers. The electroacoustic component structures are electrically connected to the external contacts through perpendicular electrical connections.

Abstract: A method for manufacturing a surface acoustic wave element including: forming a conductive film on a surface of a piezoelectric substrate; forming a photoresist film on the conductive film; printing a pattern by exposing and developing the pattern, which is originally provided on a photomask, onto the photoresist film by reduced projection; forming an electrode of a surface acoustic wave element by etching the conductive film using the patterned photoresist film as a mask; measuring a resonant frequency of the surface acoustic wave element formed on the piezoelectric substrate; calculating an anodic oxidation voltage based on an amount of anodic oxidation of the electrode that is calculated in advance from the measured resonant frequency and a preset target resonant frequency; and performing anodic oxidation based on the anodic oxidation voltage calculated in the voltage calculation step and finishing anodic oxidation after detecting an end-point of oxidation reaction of the electrode.

Abstract: A method for adjusting a frequency characteristic of an edge reflection type surface acoustic wave device includes the step of obtaining a frequency characteristic of an edge reflection type surface acoustic wave device having a piezoelectric substrate. The edge reflection type surface acoustic wave device has a pair of edges of the piezoelectric substrate which define a predetermined distance therebetween. The piezoelectric substrate is cut at a position which defines a distance that is shorter than the predetermined distance when a final frequency characteristic of the edge reflection type surface acoustic wave device is to be higher than the obtained frequency characteristic. The piezoelectric substrate is cut at a position which defines a distance that is longer than the predetermined distance when a final frequency characteristic of the edge reflection type surface acoustic wave device is to be lower than the obtained frequency characteristic.

Abstract: A CDMA base station transmitter employing the Kahn envelope-elimination-and-restoration technique includes a switching amplifier adapted to linearly amplify the low-level baseband signal derived from the digital amplitude information portion of the digital CDMA signal to be transmitted downlink. In order to achieve the wide bandwidth and high dynamic range needed to linearly amplify the low-level baseband signal derived from the digital amplitude portion of the CDMA signal, a truncating circuit truncates a predetermined number of the least significant bits of each word of the digital amplitude portion before the amplitude portion is converted to a low-level baseband signal and is amplified by the switching amplifier. High resolution is restored to the amplified output by a power-dissipating post regulator at the output of the switching amplifier.

Abstract: An acoustic wave sensor apparatus is disclosed, which generally includes a piezoelectric substrate having a surface thereon. One or more interdigital transducers and a passivation layer can be formed upon the piezoelectric substrate. Additionally, an absorbent material can be formed upon the acoustic path (IDTs, electrodes, etc), such that the interdigital transducers respond to a plurality of acoustic waves propagating across the surface of the piezoelectric substrate, thereby providing data indicative of humidity in the vicinity of the piezoelectric substrate, along with the passivation layer and the interdigital transducers. Additionally, one or more heaters can be formed upon a side of the piezoelectric substrate opposite the side of the piezoelectric substrate upon which the interdigital transducers, the passivation and the absorbent material are located. The heater can be preferably configured from a material such as platinum.

Abstract: A surface acoustic wave element includes a single crystal substrate; a buffer layer formed by a crystal film that is formed on top of the single crystal substrate; and a piezoelectric thin film having a hexagonal system or a trigonal system crystal structure that is formed on top of the buffer layer. The surface acoustic wave element has an improved performance by improving the film quality of the piezoelectric thin film. In addition, because a semiconductor device can be formed on the single crystal substrate, the surface acoustic wave element can be integrated with the semiconductor device. Moreover, leakages of surface acoustic waves into the single crystal substrate are prevented. There are also provided a frequency filter, an oscillator, an electronic circuit, and an electronic instrument that are provided with this surface acoustic wave element.

Abstract: The problem of interference and coupling between circuits that arises in reducing the size of a voltage-controlled oscillator by using low temperature co-fired ceramics (LTCC) substrate technology is alleviated. A voltage-controlled oscillator includes an amplifier a surface acoustic wave device 15 that forms a feedback circuit for the amplifier; a frequency adjuster that is provided the feedback circuit and has a filter configuration; a phase shifter 13 including a hybrid coupler having an additional controller that receives a control voltage from an external source and changes a phase in an oscillation loop; an equal power distributor 12 that equally distributes output power in the oscillation loop and outputs the power to the outside of the oscillation loop; and a delay line 16 concentratedly provided a place where coupling or interference does not occur the oscillation loop for correcting a phase condition in the oscillation loop.

Abstract: Surface acoustic wave (SAW) zebra-wave-guide (10) implemented as an array of interdigitized electrode fingers, wherein the array has internal inter-finger connectors (18) providing inside electrical shorting of part of fingers (16) remaining other fingers (14) to be isolated, moreover, the array (12) is bordered by important free surface spaces (15). Time delay and phase of the propagating SAW beam front are controlled by the varying of quantity of isolated fingers (14) of the zebra-wave-guide (10). Aggregation (40) of the parallel zebra-wave-guides having different quantities of isolated fingers (14) and different widths allows manipulations with narrow SAW beams' phases and magnitudes, that becomes helpful degree of freedom for desire transformation of the SAW beam (140).

Abstract: An assembly and method for array processing of hermetically sealed Surface Acoustic Wave (SAW) Devices employs a non-conductive material having an array of spaced cavities extending into the material for receiving a SAW die face down, in a flip-chip arrangement. Each cavity has a peripheral recess dimensioned to receive a lid for hermetically sealing the die within the cavity. Conductive paths are provided from the interior of the cavity to the surface of the array for providing an electrical contact with the SAW die. Individual SAW devices are then provided by cutting along separation lines between adjacent cavities after a plurality of die have been hermetically sealed within its cavity.

Abstract: A surface acoustic wave device applied to a filter, an oscillator, a delay element, or the like has at least a surface acoustic wave element with metal electrodes formed on a piezoelectric substrate to excite surface acoustic waves, a plastic casing base to accommodate the surface acoustic wave element inside a casing, and a plastic cap to seal a hollow in the casing. If the plastic casing base and plastic cap have the same material color, there will be a high risk of misjudging the front and back faces of a plastic package. Providing the plastic casing base and plastic cap with different material colors may reduce inserting direction errors when inserting the surface acoustic wave device into, for example, a printed board.

Abstract: A base material made of C-faced sapphire single crystal is set on a susceptor installed in a reactor arranged horizontally. Then, a trimethyl-aluminum and an ammonia are introduced as raw material gases into the reactor and supplied onto the substrate, to form an AlN film. In this case, the temperature of the base material is set to 1100° C. or over, and the ratio (V raw material gas/III raw material gas) is set to 800 or below, and the forming pressure is set within a range of 7-17 Torr. As a result, the crystallinity of the AlN film is developed to 90 arcsec or below in FWHM of X-ray rocking curve, and the surface flatness of the AlN film is developed to 20 Å or below. Therefore, a substrate composed of the base material and the AlN film is preferably usable for an acoustic surface wave device, and if the substrate is employed, the deviation from the theoretical propagation velocity is set to 1.5 m/sec or below.

Abstract: A voltage controlled oscillator is provided. The oscillator includes a surface acoustic wave element for forming a feedback circuit for an amplifier, and a phase adjustment circuit including a filter which is interposed in the feedback circuit. The oscillator also has a phase shifter including a hybrid coupler to which an additional control part is attached for changing a phase value within an oscillation loop with a control voltage supplied from an external source. An equal power divider equally distributes output power within the oscillation loop and supplies the output power outside the oscillation loop. A multi-layer board is used for mounting the amplifier, surface acoustic wave element, phase adjustment circuit, phase shifter, and equal power divider in at least two separate layers.

Abstract: Surface acoustic wave device having a high k2, and a frequency filter, oscillator, electronic circuit and electronic device employing this surface acoustic wave device is provided, wherein a first oxide thin film layer comprising SrO or MgO and a second oxide thin film layer comprising SrTiO3 are sequentially formed on top of a (110) Si substrate, or a first oxide thin film layer comprising CeO2, ZrO2 or yttrium-stabilized zirconia and a second oxide thin film layer comprising SrTiO3 are sequentially formed on top of a (100) Si substrate, a KNbO3 piezoelectric thin film being then formed on top of either of these second oxide thin film layers, and then, a protective film comprising oxide or nitride is formed on top of the KNbO3 piezoelectric thin film, finally, at least one electrode is formed on top of this protective film, to form a surface acoustic wave device, which surface acoustic wave device is employed to form a frequency filter, oscillator, electronic circuit, or electronic device.

Abstract: A piezoelectric resonator is constructed to be vibrated in a square type vibration mode and to minimize the variations in the resonant frequency caused by the manufacturing process. The resonator includes a piezoelectric substrate having a pair of main surfaces, electrodes disposed on the pair of main surfaces and grooves provided on one of the main surfaces of the piezoelectric substrate. The grooves divide at least one of the electrodes into a plurality of divided electrodes. One of the plurality of divided electrodes defines an input/output electrode. A maximum distance between the outer edges of two of the grooves disposed opposite to each other across the input/output electrode is about 0.5 to about 0.55 times the length of one side edge of the piezoelectric substrate.

Abstract: A surface-acoustic-wave filter has a piezoelectric substrate; and a plurality of transversal surface-acoustic-wave (SAW) filters set on the piezoelectric substrate and respectively having at least two inter-digital transducer (IDT) electrodes for transcieving surface acoustic waves, characterized in that periods for surface acoustic waves to propagate from inputs to outputs of the SAW filters differ in the SAW filters and thereby, timings of outputs from the SAW filters are different from each other.

Abstract: A surface acoustic wave (SAW) device that is made with diamond, that has high efficiency, and that can be operated at high frequencies, particularly from 9.5 to 10.5 GHz. The SAW device comprises a diamond layer formed singly or formed on a substrate, a ZnO piezoelectric layer, interdigital transducers (IDTs), and a short-circuiting electrode as required. The SAW device has a structure in which the thickness of the ZnO layer, the wavelength of a harmonic of the SAW, and the line width of the IDTs fall in a specified range. With this structure, a large electromechanical coupling coefficient is obtained in a high-frequency range of 10 GHz band by utilizing the third or fifth harmonic of the SAW.

Abstract: A method of manufacturing an edge reflection type surface acoustic wave device includes the step of preparing a surface acoustic wave mother substrate having a plurality of interdigital transducers formed on one main surface thereof. A cut groove is formed in the substrate by cutting the surface acoustic wave mother substrate beginning from the one main surface side thereof. This step of forming a cut groove is repeated so as to produce a plurality of cut grooves so that the first reflection edge of the respective surface acoustic wave devices are sequentially formed. Next, similarly, cut grooves are sequentially formed on the surface acoustic wave mother substrate from the one main-face side thereof so as not to reach the other main surface thereof, whereby the second reflection edges of the respective surface acoustic wave devices are sequentially formed.

Abstract: In a surface-acoustic-wave (SAW) device and method of fabricating the same, a SAW chip is flip-chip mounted in a package. The package has a window facing an electrode formed surface of the SAW chip. After the SAW chip is mounted, the in-process item is inserted into reactive ion etching equipment, with the window open. The substrate or electrodes of the SAW chip is etched by an etching gas introduced into the ion etching equipment. Films may be formed on the electrode formation surface, in place of etching. Thus, variation in characteristics stemming from variations in manufacturing processes can be suppressed.

Abstract: An acousto-optic scanning system, which relies on two counter propagating acoustic waves with the same frequency modulation. This scheme completely suppresses the linear frequency chirp, and thus enables the generation of fast non-linear scans and non-constant linear scans. By changing the phase between the modulating signals, this scheme also provides fast longitudinal scans of the focal point.

Abstract: An adaptive tuning method for a wireless communication device determines the impedance of a matching circuit relative to an impedance to be matched and adjusts the impedance of the matching circuit accordingly. A passive surface acoustic wave (SAW) device includes multiple terminated interdigital transducers (IDTs) which generate reflected SAWs when excited by incident SAWs, each reflected SAW having magnitude and phase characteristics dependent upon the particular IDT termination. According to the invention, the IDT terminations include the impedance matching circuit and the impedance to be matched. Input IDTs in the SAW device are excited with electrical signals, which are converted to generate the incident SAWs. The resultant reflected SAWs are converted by output IDTs into output electrical signal signals which can then be analyzed to determine magnitude and phase differences between the output electrical signal signals and generate an impedance matching circuit control signal based thereon.

Abstract: An acoustic charge transport device is formed by a process which introduces a process dependent variation in charge carrier density within the device. The acoustic charge transport device includes a transport channel operable to carry charge carriers in response to a surface acoustic wave. In addition, the acoustic charge transport device further includes a backgate for controlling the charge carrier density within the transport channel.

Abstract: An adaptive tuning method for a wireless communication device determines the impedance of a matching circuit relative to an impedance to be matched and adjusts the impedance of the matching circuit accordingly. A passive surface acoustic wave (SAW) device includes multiple terminated interdigital transducers (IDTs) which generate reflected SAWs when excited by incident SAWs, each reflected SAW having magnitude and phase characteristics dependent upon the particular IDT termination. According to the invention, the IDT terminations include the impedance matching circuit and the impedance to be matched. Input IDTs in the SAW device are excited with electrical signals, which are converted to generate the incident SAWs. The resultant reflected SAWs are converted by output IDTs into output electrical signal signals which can then be analyzed to determine magnitude and phase differences between the output electrical signal signals and generate an impedance matching circuit control signal based thereon.

Abstract: In accordance with the invention, magnetostrictive saw devices are provided with tunable transducer structures for enhanced performance. The transducers are in the form of patterned conductors disposed between magnetic films. The magnetostrictive response is tuned by adjusting the thickness of magnetic film overlying the conductive layer.

Abstract: SAW filter package which can reduce an electromagnetic feed-through for improving an SAW filter performance including a base having a frame around a periphery, a ground part formed of a metal plating on an inside surface of the base for attaching an acoustic surface wave filter thereto, cut-away portions formed by cutting the metal plating of the ground part in two steps, and a metal piece electrically separated from the metal plating by the cut-away portions.

Abstract: A tool holder for holding a tool has at least one sensor for measuring an operating parameter of the tool holder or the tool during the operation thereof and generating measured value signals which are fed to a signal processing unit for evaluation. The sensor is a surface acoustic wave sensor operating according to acoustic wave principles and its measured value signals are readable in a contactless manner by means of radio waves. The surface acoustic wave sensor requires no current supply circuit but instead draws transmission energy required for transmission of the measured value signals to the signal processing unit from a high frequency interrogation signal, that is transmitted by radio waves from the signal processing unit and is received by the surface acoustic wave sensor.

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 bulk acoustic wave delay line is disclosed having a thin, amorphous metal substrate, and deposited on the first and second surface at each end of which is a very thin layer of a piezoelectric material. Positioned on each piezoelectric material layered area are a plurality of interleaved electrodes with a first portion of each plurality of electrodes being interconnected and a second portion of each plurality of electrodes being interconnected. The electrodes on the first and second surface at one end of said device are energized with electrical signals in a phased or un-phased manner to generate selected modes of pure Lamb waves in said substrate.

Abstract: An improved surface acoustic wave device includes a film of a magnetostrictive material disposed on a substrate and spaced apart input and output transducer elements disposed on the film. The input element causes horizontally polarized shear waves to propagate along the film via the magnetostriction of the film. The shear waves propagating along the film are received by the output transducer element. The SAW device can be integrated on a microelectronic circuit useable in single chip radio frequency applications.

Abstract: An acoustical-electronic component operating with acoustical surface waves, includes a piezoelectric substrate in which an acoustical surface wave is guided and enters into interaction with an electron system disposed on the substrate in the travel path of the acoustical surface wave. The electron system is constructed as an electron channel that is tunable in its electrical conductivity by field effect. A tunable delay line, a resonator and a semiconductor sensor use the component.

Abstract: A method (100) of providing a time delay to a signal utilizing a surface acoustic wave ladder filter includes a first step (102) of providing a piezoelectric substrate. A second step (104) includes disposing series and shunt coupled surface acoustic wave transducers in a ladder configuration on the substrate with each of the transducers having an associated aperture and an associated number of interdigital electrode elements. A third step (106) includes configuring the associated aperture and an associated number of interdigital electrode elements for each surface acoustic wave transducer for maximum phase linearity of the ladder filter and uniform group delay response from the ladder filter. A fourth step (108) includes adjusting the number of transducers in the ladder filter to provide a desired average group delay. Subsequently passing a signal through the ladder filter will delay the signal by a time equal to the group delay.

Abstract: The transducer according to the invention, driven in differential mode, consists of at least a first transducer (5) and a second transducer (6) which are connected in parallel so as to obtain the symmetry of the differential inputs, respectively forming a first and a second acoustic channel; the two transducers (5, 6) exhibiting a specified longitudinal offset with respect to one another. Applications: mobile radio filters.

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 programmable signal translating device, praticularly a transversal filter, includes a wave transport body for transporting a wave along its length, a first channel of electrical conductors having a plurality of code sections spaced along its length for generating phase-coded electrical signals from the wave propagated by the transport body, a second channel of electrical conductors connected in parallel to the first channel and of identical code sections as, but of opposite polarity to, the first channel, and programmable electrical connections between the code sections of the first channel and the code sections of the second channel and the output circuit, for connecting selected code sections of the first and second channels to the output circuit.

Abstract: A fast pattern recognition system includes a combination of digital and analog processing circuitry which allows the system to achieve super computing processing speeds within an open personal computer architecture. The system receives a bit map which is representative of the unknown pattern, such as a picture of an unknown person. The bit map could have multiple people in it--no other system has "faces in the crowd" ability. The bit map associated with the unknown pattern is then pre-processed and compared against a plurality of known patterns in a database using a dispersive delay line, to determine how well the unknown pattern correlates with the known patterns.

Abstract: A filter operating with acoustical harmonic waves includes at least one resonator being formed of an interdigital converter and reflectors. An electrical resistor is connected parallel to at least one filter component for protecting against electrostatic discharge from contact with electrostatically charged parts. The electrical resistor is integrated with one or both of the reflectors of the resonator.

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: The invention concerns unidirectional ground-wave transducers using an alternating series of emitter cells (E) and reflector cells (R).The invention consists in using, in the emitter cells (E), fingers having a width of .lambda./3 spaced apart by a distance of 2 .lambda./3; and, in the reflector cells (R), fingers having a width of .lambda./4 spaced apart by a distance of .lambda./2.Using identical engraving precision, the invention makes it possible to increase by 50% the frequency at which the unidirectional transducer thus produced can be used.

Abstract: To obtain a surface acoustic wave device which can be produced with ease at a low cost and can be reduced in size without causing deterioration of characteristics, a surface acoustic wave device having input and output transducers arranged alternately on the surface of a substrate for propagating a surface acoustic wave includes metal patterns provided outside the transducers along the extension line of the propagation path of the surface acoustic wave and having at least one surface inclined at an angle .theta. (5.degree.<.theta.<85.degree. or -85.degree.<.theta.<-5.degree.) with respect to the propagation direction of the surface acoustic wave.

Abstract: A pair of crystallographically matched piezoelectric substrates are sealed together to provide a package for a SAW device. A sealant material including a glass frit is deposited on a selected portion of a first one of the pair of substrates. The substrate having the sealant material is then heated to a temperature which is substantially below the glazing temperature of the sealant material to dry the sealant material. The substrate having the dried sealant material is heated a second time at a temperature just above the softening temperature of the glass frit to glaze the glass frit component with other components of the sealant material being driven from the glass frit during the heating cycles. The substrate having the glazed frit and the other remaining substrate are then mated together in a predetermined manner.

Abstract: This invention provides a delay circuit capable of electrically varying the delay amount comprising a first transistor for receiving a signal to be delayed from the base connected to an input terminal and outputting a positive phase signal and a negative phase signal with respect to the signal from the input terminal, respectively from the emitter and the collector thereof; two variable capacity diodes with their terminals of the same polarity connected together and a specified control voltage applied to the point of said connection, one end of the connected diodes being connected to the emitter of said first transistor; a second transistor with the base grounded, the emitter connected to the collector of the above-mentioned first transistor, and the collector connected to one end of a specified resistance; and a delayed signal output terminal having connected thereto the other end of the two variable capacity diodes and the other end of the specified resistance.

Abstract: A surface-wave-type reflective delay line includes an input/output interdigital converter, and a plurality of surface wave reflectors. The surface wave reflectors are disposed at positions corresponding to an order of magnitude of half of a particular desired transit time of a surface wave between the input/output interdigital converter and an applicable surface wave reflector and back. At least some of the surface wave reflectors are each shifted by a mathematically random value out of the positions corresponding to half the particular desired transit time.

Abstract: Disclosed herein is a surface acoustic wave device employing diamond, which has an operation frequency in a range of several hundred MHz to several GHz, a high propagation velocity and a large electromechanical coefficient. This surface acoustic wave comprises a substrate, a diamond layer which is formed on the substrate, a ZnO layer which is formed on the diamond layer, and interdigital electrodes which are formed on the ZnO layer, and utilizes a second order mode of a surface acoustic wave which is excited in a structure satisfying (2.pi..H/.lambda.)=0.9 to 2.3 where H represents the thickness of the ZnO layer and .lambda. represents the wavelength of the surface acoustic wave. This surface acoustic wave device can be used in an extremely high frequency range, whereby the same is applicable to a resonator, a delay line, a signal processing device, a convolver, a correlator or the like in addition to a filter.

Abstract: A heterojunction acoustic charge transport (HACT) device having a charge transport layer 16 surrounded by upper and lower charge confinement layers 14,30, respectively, and having a cap layer 36 at the outer surface, above the upper confinement layer 30, is provided with a P-N junction to minimize the effects of surface states. An intermediate layer 34 is disposed between the cap layer 36 and upper charge confinement layer 30. The upper confinement layer 30 and intermediate layer 34 are doped with opposite polarities to provide a P-N junction which creates a built-in electric field having sufficient strength to keep mobile charge carriers, transported by a SAW along the charge transport channel, from being trapped by or recombined with surface states at the external interface of the cap layer 36. Alternatively, the intermediate layer is not present and a cap layer 42 is doped to provide one side of the P-N junction.

Abstract: A convolver has a piezoelectric film layer, an insulator layer and a semi-conductor layer. A surface resistance measurement part permits measurement of a surface resistance related to the surface resistance seen by a gate electrode of the convolver. The surface resistance part is changeable by a bias voltage applied to the convolver. The amplitude of the bias voltage is controlled to set the surface resistance at a value which produces a desired convolution efficiency of the convolver. The convolver is adaptable to be fabricated as an integrated circuit with a simple structure. A transmitter/receiver system is disclosed in which a transmitted SSC signal is modulated by a pseudo-noise (PN) signal, as well as by a normal modulation. In the receiver, the PN component of the signal is removed using a convolver according to the present invention, to correlate the received signal before detection thereof.

Abstract: A sampling device operating as a buffer between a first data signal and a relatively slow processing device accepts the input signal and stores samples of it on a SAW traveling past an input electrode. A blocking potential is applied to a set of electrodes to store a set of charge packets with the SAW device. Packets are consecutively released at a slower rate accommodated to the needs of the next processing unit in line, to read out the sampled signal at a modified rate for intentional distortion of the input signal, for slowing the output stored signal rate, or for time reversal of the signal.

Abstract: An SAW (surface acoustic wave) device is disclosed, in which a plurality of SAW delay lines and a plurality of SAW convolver elements are combined; signals delayed by predetermined amounts by the combined SAW delay lines are used as input signals to the SAW convolver elements; and output signals thus obtained from the plurality of SAW convolver elements are added together to be taken out so that apparently a processing time, which is equal to a signal processing time of a single SAW convolver element multiplied by an integer, can be obtained.

Abstract: An acoustic delay line includes electrodes on a monolithic piezoceramic substrate, which serve as electro-acoustic transducers for the delay line. The distance between said transducers defines the transit time, and thus the delay path. Each transducer may have electrodes on the same side of the substrate, in which case thickness of the substrate is less than or equal to one-half the wavelength of the highest frequency to be transmitted in the substrate, so as to prevent the formation of higher modes. Alternatively, each transducer may have congruent electrodes on opposite sides of the substrate, in which case the thickness of the substrate is less than or equal to the wavelength of the highest frequency to be transmitted. The substrate is polarized substantially parallel to the equipotential lines which arise in the substrate upon the application of a voltage to the electrodes.

Abstract: A bias control device for a narrow band interference suppressing filter using a surface acoustic wave (SAW) element is disclosed, in which bias shift signals corresponding to spectre intensities of channels having central frequencies different from each other outputted from the filter are caught as digital data; magnitudes of the data are compared and at the same time the channel numbers are sorted in the order of the spectre intensities; and control signals for the filter are generated in this way.

Abstract: A strip coupled type convolver includes an aluminum nitride (AlN) layer and a semiconductor layer both provided on a single sapphire substrate, and includes many metal strips extending across a surface wave propagating path on a surface of the AlN piezoelectric layer to transmit a potential on the piezoelectric surface to a Schottky diode array provided on the semiconductor surface to cause a nonlinear interaction.