Abstract: A tunable analog noise-cancelling transversal reconfigurable filter for filtering an RF signal. The filter includes a noise-cancelling balun responsive to the RF signal and providing gain and noise suppression, and a time delay network responsive to the signal from the balun. The time delay network includes a single continuous three-dimensional air coaxial line where a separate tap is provided between sections of the line. The filter also includes a multiplication and summing network having a plurality of multiplication stages, where each stage is fed by a voltage signal from at least one of the taps, and each stage includes a multiplication amplifier that amplifies the voltage signal. A tuning element provides a multiplication coefficient to the amplified signal. Each amplified signal in each stage is added on an output line, where the multiplication and summing network operates under Millman's Theorem.

Abstract: Programmable SAW filter module are provided to overcome undesirable drawbacks, limitations and shortcomings associated with “in-line” SAW filters, such as insertion loss, propagation loss and strong signal capture effects. The programmable SAW filter modules remove the SAW structure from the primary signal path, adding signal gain to drive the splitter and using the SAW portion of the circuit as a programmable impedance element. The programmable SAW filter module includes an amplifier, an impedance, a surface acoustic wave propagation element, a splitter, input and output IDT electrodes, input and output interdigitated transducers, means for gain control and a combiner to combine or sum the signals received from the output IDT electrodes and form an output signal. The input and output IDT's are fully integrated circuits comprising the power splitter and power combiner functions, the phase shift, and gain functions.

Abstract: Channel quality can be detected accurately in a wireless transmission system such as an HSDPA method. In the case of estimating a channel quality of a signal transmitted by a Code Division Multiple Access method and of estimating the channel quality in a system having a synchronization channel not orthogonal to a channel receiving data, a noise component of a desired channel is estimated; degree of a noise component caused by the synchronization channel is estimated with respect to the estimated noise; and a channel quality of a receiving channel is detected based on the estimated degree of the noise component.

Abstract: The present invention discloses a double TRU (Transceiver Unit) (45). The output signals from the power amplifiers (64, 84) are combined to one common output signal provided to an antenna arrangement (91). A DSP (Digital Signal Processor) (52, 72) of each TRU (50, 70) comprises means for a constant-envelope modulation scheme (54, 74) and a non-constant envelope scheme (53, 73). The DSP:s (52, 72) select the modulation scheme according to modulation information (49, 69). In such a way, a switching between different modulation schemes can be performed even on a time-slot basis. For non-constant-envelope modulation, the modulated signal is separated into two component signals. Each TRU (50, 70) takes care of the amplification of one component. A phase compensation of at least one of the TRU:s (50, 70) is performed in order to correct for different paths of phases of the power amplifiers (64, 84). The non-constant envelope modulated signal can also be a multi-carrier signal, e.g.

Abstract: A radio communication method and system for transmitting multiple-user digital data information in a Code Division Multiple Access (CDMA) format over multipath and mutual-interfering channels to a receiving terminal with diversity antennas and equalization signal processing. At the receiving terminal, diversity antenna signals are grouped into time blocks and replicas are generated of the user-unique CDMA sequence signals for a set of K mutually interfering users. Within each time block the multiuser channel is estimated, equalization parameters are calculated, and decision-feedback equalization is used to produce multiuser estimates associated with a subset ? of the K users. These estimates are deinterleaved and error-correction decoded to recover transmitted digital data information for the subset of ? users.

Abstract: The number of times for averaging operation for averaging a correlation value of a received signal and a reference signal is properly controlled. When the correlation value is not averaged, since a lower limit value TH_A of a correlation level of a distribution of timings of which a path exists is larger than an upper limit value TH_B of a correlation level of a distribution of timings of which a path does not exist, the correlation value of a path is hidden by noise. Since the averaging operation is repeated until the relation of TH_A>TH_B is satisfied, the averaging operation is stopped when the relation is satisfied. The TH_A and TH_B are decided in accordance with RSCP and ISCP of a pilot channel and RSSI of a received base band signal.

Abstract: A method of Partial Parallel Interference Cancellation (PPIC) is provided for recursively eliminating the Multiple Access Interference from a received signal. Such method is to use a recursion way to eliminate all the Multiple Access Interference (MAI) one by one from the received signal. Moreover, the present invention is to take the output of the pre-stage as the input of the present stage with the recursion method so that we can use only one operating circuit to obtain the function the MAI eliminating.

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 ZnO monolithically integrated tunable surface acoustic wave (MITSAW) device uses tunable acousto-electric and acouso-optic interaction between surface acoustic waves (SAW) and a two dimensional electron gas (2DEG) in a ZnO/MgxZn1−xO quantum well. The high electromechanical coupling coefficients of piezoelectric ZnO in conjunction with the low acoustic loss and high velocity of sapphire (Al2O3) offers high frequency and low loss RF applications. The 2DEG interacts with the lateral electric field resulting in ohmic loss which attenuates and slows the surface acoustic wave. This mechanism is used to tune the acoustic velocity. The high coupling coefficients offered by the ZnO/R—(Al2O3) systems allows large velocity tuning. Combined with the optical characteristics of the wide and direct band gap (about 3.3 eV) semiconductor and transparent ZnO electrodes, the MITSAW chip can be used for UV optical signal processing.

Abstract: A ZnO monolithically integrated tunable surface acoustic wave (MITSAW) device uses tunable acousto-electric and acouso-optic interaction between surface acoustic waves (SAW) and a two dimensional electron gas (2DEG) in a ZnO/MgxZn1-xO quantum well. The high electromechanical coupling coefficients of piezoelectric ZnO in conjunction with the low acoustic loss and high velocity of sapphire (Al2O3) offers high frequency and low loss RF applications. The 2DEG interacts with the lateral electric field resulting in ohmic loss which attenuates and slows the surface acoustic wave. This mechanism is used to tune the acoustic velocity. The high coupling coefficients offered by the ZnO/R-(Al2O3) systems allows large velocity tuning. Combined with the optical characteristics of the wide and direct band gap (about 3.3 eV) semiconductor and transparent ZnO electrodes, the MITSAW chip can be used for UV optical signal processing.

Abstract: An acoustic wave identification transponder device, having a substrate, an electroacoustic transducer generating an acoustic wave in said substrate and a set of encoding elements disposed in a path of the acoustic wave for modifying the acoustic wave, having elements which reflect portions of the acoustic wave having a component orthogonal to the incident wave. The reflectors may be, for example, trackchangers or reflective arrays compressors (RAC). The wave may be phase-amplitude modulated for increased efficiency expressed in bits per tap. Such phase amplitude modulation is preferably imposed by partial beam width phase delay elements disposed within an acoustic beam path.

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: Electrical components, such as filters, oscillators, resonators and delay lines are manufactured from a piezo ceramic base which includes a depolarized zone. The sound velocity is set by topically heating a portion of the base to form the depolarized zone between a pair of transducers.

Abstract: An acoustic device has an acoustic wave propagating medium exhibiting elastic abnormality in the vicinity of a Curie temperature. It is desirable that such an acoustic wave propagating medium be formed of a ferroelectric substance or a high-elastic substance and, in particular, have a Curie temperature at normal temperatures. For example, such ferroelectric substance is a solid solution expressed by Cs(Pb.sub.1-x Sr.sub.x)(Cl.sub.1-y Br.sub.y).sub.3 or (Bi.sub.1-x Dy.sub.x)VO.sub.4. By changing values of x and y appropriately, the Curie temperature of the solid solution can be varied, and an acoustic wave propagating medium meeting the purpose of use can be obtained. In such an acoustic wave propagating medium, an elastic coefficient C.sup.P at the time of constant polarization differs greatly from an elastic coefficient C.sup.E at the time of a constant electric field in the vicinity of the Curie temperature. Accordingly, the propagation velocity of acoustic waves is greatly different, too.

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 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: A high speed analog to digital converter system employs a set of ACT devices in parallel to buffer a high speed data sampling rate to the processing rate of the analog to digital converters employed. Vernier control of phase between individual devices is maintained by controlling the speed of propagation of the SAW wave by illumination of the substrate in response to a phase comparison between the SAW and a reference signal.

Abstract: A tapped delay line uses a varistor network for tap weighting. The varistors may be used in a resistive summing network or as amplifier gain control elements. In addition, the varistors can be programmed by a voltage programming circuit comprising a switch array, an input voltage programming bus, and sets of master and slave digital programming signals.

Abstract: An SAW convolver is disclosed, in which a pair of input transducer means disposed at the left and right end portions on a piezoelectric substrate having a velocity dispersion consists of a plurality of pairs of input transducers and the distance between different pairs of input transducers differs from each other so as to compensate the velocity dispersion.

Abstract: A heterostructure acoustic charge transport (HACT) device having a number of signal tap electrodes has revealed unexpected insensitivity to electrode spacing and unexpected sensitivity to electrode width. Spacing of one SAW wavelength between consecutive electrodes and an electrode width of .lambda./20 are preferred.

Abstract: A delay device comprises a semi-conductor chip having acoustic charge transport channel disposed therein; a contact operably connected to and disposed at one end of the channel for injecting an electronic signal into the channel; a transducer for generating a single frequency, large amplitude acoustic surface wave through the channel for thereby transporting the electronic signal through the channel; a plurality of electrodes operably associated with the channel and disposed along the propagation path of the surface acoustic wave for non-destructively sensing the electronic signal; switches monolithically disposed on the chip and operably connected to the electrodes for preselecting any one of the electrodes, thereby extracting a delayed replica of the signal from the channel; and an output circuit for processing the extracted signal for generating an output.

Abstract: A simplified heterostructure charge transport device has a GaAs transport layer that is the top layer of the device, deposited on an (Al,Ga) As barrier layer for vertical confinement of charge packets. Confinement at the top surface is provided by pinning of the conduction band surface states.

Abstract: A method of adjusting the center frequency of a SAW device by providing a substrate capable of propagating a surface acoustic wave thereon having input transducer electrode on one end portion thereof, output transducer electrodes on the opposite end portion thereof and a waveguide portion therebetween, applying an RF input signal to the input transducer and providing an indication of the output obtained from the output transducer and etching the entire device with an etchant until the indication has reached a predetermined status.

Abstract: A SAW device tapped delay line includes an apodized input IDT (inter-digital transducer) and a plurality of substantially identical unapodized output IDTs arranged to receive, after delays which successively increase by an amont T, a SAW propagated from the input IDT. Each output IDT is terminated with a low impedance which is constituted by the low input impedance of a buffer amplifier, to minimize acoustic regeneration by the output IDTs. Grounded dummy fingers with the same metallization ratio as the output IDTs are provided between adjacent output IDTs to provide a constant SAW velocity. The delay line is particularly suited to use in an equalizer of a microwave radio transmission system, in which the delay T is the inverse of the symbol rate of the system. Intermediate frequency automatic time domain equalizer (IF ATDE) arrangements using the SAW device tapped delay line are described.

Abstract: In an SAW convolver composed of a substrate having a multi-layered structure comprising at least a piezoelectric film, self convolution is suppressed by disposing a first and a second array electrode disposed between the gate electrode and a pair of input electrodes, respectively, each of which consists of a high impurity concentration semiconductor layer. Further a convolution integrator is constituted by using such a convolver.

Abstract: An acoustic charge transport (ACT) device is easily constructed to provide for variable carrier frequency operation or, alternatively, for variable time delays. Variable carrier frequency operation in an ACT device is achieved by incorporating a two dimensional dispersive transducer array which has an interdigitated finger arrangement. This array has a graded periodicity or finger spacing that varies along the length of the array and also has the fingers placed at a 45 degree angle with respect to the length of the array. Because of the varying spacing of the electrode fingers, different spatial regions in the piezoelectric substrate are preferentially excited reflecting the presence of specific frequency components in an applied input signal. A variable time delay is similarly achieved in an ACT device by incorporating a two dimensional interdigital transducer array having fingers with a graded periodicity.

Abstract: The difficulty of making Doppler shift velocity measurements in a chirp pulse echo ranging system is overcome by employing a pulse frequency compression filter, suitably a SAW compressor 45, having individual outputs 64, 65, 66, 67 respectively relating to adjacent contiguous frequency bands A, B, C, D, (FIG. 3) each having a bandwidth approximately equal to the chirp frequency swing. Signal detection and processing means 70 senses the occurrence of a compressed pulse on any of the outputs and measures the amplitudes of signals on all the outputs. A computer then computes the Doppler shift from the amplitude ratio of the sensed signals to adjacent frequency bands, determines the target velocity therefrom and uses the result also to correct the range measured by the counter 5.

Abstract: A clock regeneration circuit which is formed as an integrated circuit except for a SAW (surface acoustic wave) filter module which can be used unaltered for a number of regeneration circuits which are provided for various clock frequencies and the design of the SAW filter modules for such regeneration circuits are designed such that the SAW filter modules have an increasing phase for decreasing clock frequency. An in-phase data rate generation is possible even though the integrated circuit always supplies the filter module with pulses of identical lengths for all clock frequencies and an improved clock regeneration circuit results.

Abstract: A monolithic SAW convolver comprises a piezoelectric film, an insulator, a semiconductive epitaxial film and a high-concentrated semiconductive substrate. The semiconductive epitaxial film has a thickness in a predetermined range to improve the efficiency and the temperature property of the convolver.

Abstract: A variable analog delay line apparatus utilizing a plurality of tapped SAW devices that are connected in series by single pole multi-throw switch units. The amount of delay is determined by the switch throw arm of the switch unit that is associated with the SAW device. The delay times are added serially to obtain the needed delay.

Abstract: A surface acoustic wave device includes a semiconductor substrate, a piezoelectric film disposed on the semiconductor substrate, at least one pair of comb-shaped electrodes constituting an input transducer, and an output transducer a plurality of surface acoustic wave filters having different bands, which include a plurality of metal electrodes, so disposed that each of them is located between the input and output comb-shaped electrodes of each of the surface acoustic wave filters, a bias voltage applying arrangement for applying bias voltages to each of the metal electrodes; and a bias voltage regulating arrangement for regulating the bias voltages.

Abstract: A monolithic surface acoustic wave convolver has a structure of piezoelectric layer/insulative layer/p(n)-type semiconductive layer/n(p)-type semiconductive layer/n.sup.+ (p.sup.+)-type semiconductive substrate in which the p(n)-type semiconductive layer has a uniform thickness, and its acceptor (donor) concentration and thickness are selected to allow a depletion layer to expand throughout it under zero bias. The p(n)-type semiconductive layer and n(p)-type semiconductive layer are made by epitaxially growing the n(p)-type semiconductive layer on the n.sup.+ (p.sup.+)-type semiconductive substrate and subsequently change the conductivity of the surface portion of the epitaxial layer by impurity diffusion or ion implantation.

Abstract: The surface acoustic wave device comprises an elastic substrate, a piezoelectric film deposited on the elastic substrate, and transducers and matching circuits both provided on the piezoelectric film or along the interface between the piezoelectric film and the elastic substrate.

Abstract: A passive transponder for use in an interrogation/transponder system comprises a substrate having a substrate surface defining a path of travel for surface acoustic waves; a launch transducer element arranged on the surface for converting interrogating signals into surface acoustic waves which propagate along the path of travel; a plurality of tap transducer elements arranged on the surface at spaced intervals along the path of travel for converting surface acoustic waves into respective output signals; and a circuit, connected to the tap transducer elements, for combining the output signals of these transducer elements to form reply signals. In order to control the delay time from transducer element to transducer element, one or more "delay pads" are provided on the substrate surface between these transducer elements.

Abstract: An electrostatic voltage sensor which includes a surface acoustic wave propagating medium and transmitting and receiving transducers coupled to the medium. The voltage sensor is provided with a separate voltage collecting member different from the electrode for applying a voltage or electric field, and the voltage obtained in the voltage collecting member is varied by a predetermined frequency for being applied to the electrode so as to detect external voltage by the variation component of the oscillating frequency.

Abstract: An surface acoustic wave device, especially amplifier which includes input and output means for electrical signals provided so as to be spaced on a surface of a piezoelectric material which comprises a laminate in combination with a semiconductor, and an electrode provided in a surface signal wave propagation path between said input and output means for supplying pumping power.

Abstract: In the last section of a delay line having coupled cavities for a traveling-wave tube, the following parameters are progressively increased in the direction of propagation of the electron beam: the diameter of the opening provided for the passage of the electron beam, thus making it possible to ensure better transmission of the beam and consequently to ensure higher efficiency as well as lower heat build-up; the ratio (D.sub.2 -D.sub.1)/2 of the cavity nozzles; and the thickness of the walls which are common to two adjacent cavities.

Abstract: A variable delay line for surface acoustic waves includes spaced input and output transducers affixed on the wave-propagating surface of a piezoelectric substrate for sending and receiving acoustic waves. An AC or DC voltage is applied to the substrate through a pair of electrodes as a strain inducing signal. The applied voltage changes the time delay of the wave by physically altering the length of the propagation path, and/or by altering the effective properties of the substrate to vary the propagation velocity of the wave. The time delay will vary proportionately in response to the applied voltage.

Abstract: A surface acoustic wave resonator formed on a semiconductive piezoelectric substrate (9) has arrays (10, 11) of reflector elements forming rectifying junctions with the substrate, a voltage is impressed between the arrays and related ohmic ground contacts (12, 13) for controlling the carrier concentration beneath the arrays so as to vary the acoustic velocity therebeneath, thereby to tune the resonator. The resonator may include two acoustoelectric transducers (16, 17) for connection with an amplifier in an oscillator loop, or may have but a single acoustoelectric transducer (20) for interconnection between the elements of an oscillator circuit (21).

Abstract: A surface acoustic wave variable time delay includes a surface acoustic wave device (10) which is secured within a housing (30). The device (10) is provided with an input transducer (12) and an output transducer (16) which are respectfully connected to input lines (14) and output lines (18). An electrostrictive element (20) is secured within housing (30) between an end of device (10) and an interior wall (34) of housing (30). A control signal is applied to electrodes (22, 24) connected to element (20) to vary the size thereof. Element (20) applies a mechanical force to the surface acoustic wave device (10) to alter the distance between the input transducer (12) and output transducer (16) to thereby control the delay time between the signal supplied to the input lines (14) and the output signal at the output lines (18).

Abstract: A continuously variable delay line (10) includes a piezoelectric crystal (12) having an input transducer (14) and an output transducer (16). An input signal is transmitted through input lines (18) to the input transducer (14) and received through output lines (20) from the output transducer (16). The input signal is converted to a surface acoustic wave for transmission across the surface of crystal (12). Control electrodes (22 and 24) are applied to surfaces of the crystal (12) and are connected to control lines (26). A control signal is applied to the control lines (26) to apply an electric field to the crystal (12). The electric field thus applied alters the longitudinal dimensional characteristic of the crystal (12) and thereby controls the propagation distance between the input transducer (14) and the output transducer (16).

Abstract: An oscillator including two magnetostatic wave delay lines of different lengths formed on the surface of a magnetic material, one of whose ends is common and made by a first microstrip coupler, each of the other ends being made of a second and a third microstrip couplers respectively. The two lines are looped by means of a single amplifier. By selecting the two lengths, it is possible to obtain the desired interval between modes in such a way that there is a single oscillation mode comprised in the pass-band of the strips, in a pre-determined tuning band. This oscillator operates in the microwave range.

Abstract: An electrically controlled surface acoustic wave (SAW) delay unit includes a piezoelectric and semiconductive substrate having a segmented rectifying contact disposed on the surface of an interaction region between launching and detecting transducers, with a controllable voltage applied to the rectifying contact, thereby to vary the concentration of carriers in the semiconductive material, so as to commensurately alter the velocity of surface acoustic waves in the module. The segmented contact provides significant increase in the achievable variation in velocity, and therefore in phase as well. An oscillator configuration includes such a module with an amplifier and other circuit elements formed integrally therewith in a monolithic fashion.

Abstract: The treatment is directly effected on the waves propagated. Zones, for creating interruptions in propagation, are created on the useful surface of the propagation material. Several parallel tracks for propagating the elastic waves are thus delimited by these zones, the length and width of which are selected in dependance upon the required treatment.

Abstract: An improved SAW pressure sensor structure includes a dual substrate sensor having a SAW substrate with a SAW delay line disposed in an active signal region on a first one of two parallel major surfaces thereof, and having a centrally apertured base substrate of the same material bonded at a mating surface thereof to the second one of the SAW substrate major surfaces with a glass seal, the dual substrates being bonded in crystallographic orientation, the central aperture having segmented portions to provide a major diameter opening at the mating surface coextensive with the active signal region to form a diaphragm and having a minor diameter opening at a second surface of the base substrate at a value less than one half that of the major diameter, the base substrate further including an O-ring groove adapted to receive one end of a cylindrical metal sleeve in a vacuum sealing relationship, the metal sleeve having a diameter equal to one half that of the aperture major diameter, the sleeve being bonded at anoth

Abstract: A SAW signal processor includes a plurality of FET taps having individually programmable source-drain bias which controls both the amplitude and the phase of the mixing efficiency of internal product mixing of waves passing beneath the tap, in dependence upon the amplitude and polarity of the bias, the gates of the FETs may be interconnected so as to provide a summation of correlation at the output. Embodiments include multi-FET taps formed on substrates that are both semiconductive and piezoelectric, such as n-type epitaxial gallium aresenide, and ZnO coated silicon. Simple biphase and weighted biphase of phase-shifted tap pairs, for complete phase control, are disclosed.

Abstract: A surface acoustic wave (SAW) device formed by an unitary insulating, magostrictive ferrite, slab whose easy axis of magnetization is initially (prior to the application of a d.c. magnetic biasing field) perpendicular to the direction of SAW-wave propagation. For example, the easy axis of magnetization in a single-crystal lithium ferrite slab is the <111> axis. Therfore this axis is aligned perpendicular to the SAW wave propagation direction and parallel to the edges of the SAW device. Application of a dc magnetic field swings the magnetic moments such that they will be parallel with the SAW wave propagation. Materials useful in carrying out this invention are those which have (1) an easy axis of magnetization, (2) good insulator qualities and (3) the magnetostrictive property. A dc magnetic field is applied parallel with the SAW direction or perpendicular to the easy axis of the material in order to align the magnetic moments in the direction of the SAW wave propagation.