Abstract: A vehicle wireless data communication system of the invention comprises: a portable device including wireless data communication means and storing means for storing a network setting-up code; and a vehicle carried device including wireless data communication means and storing means for storing a network setting-up code corresponding to the network setting-up code of the portable device, wherein when the portable device approaches to a position within a communication range of the vehicle carried device (S1), an inquiry communication is carried out to compare the network setting-up codes for verification (S2), and when the network setting-up codes are coincident with each other (S3, S5), a wireless link is set up and the vehicle carried device is rendered active (S6).

Abstract: A vehicle wireless data communication system of the invention comprises: a portable device including wireless data communication means and storing means for storing a network setting-up code; and a vehicle carried device including wireless data communication means and storing means for storing a network setting-up code corresponding to the network setting-up code of the portable device, wherein when the portable device approaches to a position within a communication range of the vehicle carried device (S1), an inquiry communication is carried out to compare the network setting-up codes for verification (S2), and when the network setting-up codes are coincident with each other (S3, S5), a wireless link is set up and the vehicle carried device is rendered active (S6).

Abstract: A spread spectrum receiver using a correlator includes a pattern matching circuit for deciding presence or absence of a pulse output which is obtained upon coincidence between the pattern of a correlator output and a predetermined pattern, so as to switch a PN code inside the receiver or the center frequency of a received signal when absence of the pulse output is acknowledged.

Abstract: The present invention is a spread spectrum communications system where the plural pseudonoise codes are switched such that one pseudonoise code represents binary "1" and another pseudonoise code represents binary "0" of the binary data to be transmitted. Further, in the receiver, a reference pseudonoise code is generated which is asynchronous with respect to the carrier and with respect to the pseudonoise codes of the transmitter. The reference pseudonoise code is used in a convolver to reproduce the transmitted information signal.

Abstract: A surface-acoustic-wave device includes at least two surface-acoustic-wave transducers made from metal and disposed along a surface acoustic wave propagating direction on a piezoelectric substrate. At least one of the transducers has a different bandwidth, and a convolver output gate electrode in the form a rectangular metal layer is provided between the transducer having the different bandwidth and another transducer.

Abstract: A differential phase shift keying convolver having a plurality of tracks includes at least one track where an opposite phase convolution output is produced. Each track includes two output gates spaced at the center for differential phase shift keying demodulation. Among these output gates, some gates selected in accordance with the phase relationship between convolution outputs are connected to provide sum and/or difference outputs of the convolution signals. The opposite phase convolution outputs can be produced by arranging at least one of the input transducers in a step-like configuration, by using multistrip couplers, or by providing a metal film in a selected position of the traveling path of surface acoustic waves for application of a control voltage.

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: The surface acoustic wave device includes a plurality of output gate electrodes provided between two signal input transducers on a piezoelectric layer on a semiconductor substrate, so that each output gate electrode receives a bias voltage unique to it and supplies an output signal based on the unique bias voltage.

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 surface acoustic wave device comprises an elastic substrate; a lower electrode provided on the elastic substrate; a piezo-electric film covering the lower electrode; and plural upper electrodes which each include plural electrode fingers and are aligned with and spaced from each other on the piezoelectric film in confrontation with the lower electrode.

Abstract: A surface acoustic wave device comprises a piezoelectric substrate, a pair of transducers provided on the piezoelectric substrate, a center electrode provided in the center between the both transducers, first shield electrode provided between one of the transducers and the center electrode, and second shield electrode provided between the other transducer and the center electrode, with placement substantially represented by: ##EQU1## where l.sub.1 is the width of the individual shield electrodes, l.sub.2 is the distance from the individual shield electrodes to the center electrode, .lambda..sub.0 is the wavelength of a surface acoustic wave at the center frequency, and n.sub.1 and n.sub.2 are whole numbers.

Abstract: A surface acoustic wave device comprises a silicon substrate, an aluminum nitride layer provided on the silicon substrate, a zinc oxide layer provided on the aluminum nitride layer, and electrodes provided on either the silicon substrate, aluminum nitride layer or zinc oxide layer. Propagation is in the [001]- or [011]-axis direction on (100) Si, [001]- or [110]-axis on (110) Si, [112]-axis on (111) Si, or [111]-axis on (112) Si.

Abstract: A surface acoustic wave device comprises a silicon substrate, a silicon dioxide layer provided on the silicon substrate, a zinc oxide layer provided on the silicon dioxide layer and input and output electrodes provided on the zinc oxide layer. The silicon substrate is cut by a crystalline surface substantially equivalent to the (100)- or (110)-surface, and the zinc oxide layer is such that its crystalline surface substantially equivalent to the (0001)-surface is parallel to the cut-surface of the silicon substrate, so that a surface acoustic wave entered from the input electrode is propagated to the output electrode in a direction substantially equivalent to the [011]- or [001]-axis of the silicon substrate.

Abstract: A surface acoustic wave device comprises a silicon substrate, a conductive layer provided on the silicon substrate, a silicon dioxide layer provided on the conductive layer, input and output electrodes provided on the silicon dioxide layer for input and output of a surface acoustic wave, and a zinc oxide layer provided on the electrodes. The silicon substrate is cut by a crystalline surface substantially equivalent to the (111)-surface, and the zinc oxide layer is such that its crystalline surface substantially equivalent to the (0001)-surface is parallel to the cut-surface of the silicon substrate, so that the surface acoustic wave entered by the input electrode travels to the output electrode in a direction substantially equivalent to the [112]-axis of the silicon substrate.

Abstract: The parametric amplifier includes plurality of parameter changing or exciting regions provided in a periodic array on a wave propagation medium having the property that waves having different frequencies travel through the medium at different velocities, so as to cause a parametric action only when a wave applied to the amplifier satisfies a predetermined condition relative to the dispersive nature of the medium.

Abstract: Acoustic surface wave device comprising a lower electrode disposed on an elastic substrate and an upper electrode consisting of two comb-shaped electrodes disposed apart from each other, opposite to said lower electrode through a piezoelectric film covering said lower electrode, at least one of said lower and upper electrodes being constructed as an apodized electrode.

Abstract: Variable capacitance device consisting of a semiconductor substrate having a first conductivity type semiconductor layer, at least one second conductivity type semiconductor region formed in a surface portion of said first conductivity type semiconductor layer, and a barrier for generating a depletion layer formed on the surface opposite to said surface portion of said first conductivity type semiconductor layer, in which a capacitance reading-out section is disposed on said at least one second conductivity type semiconductor region.

Abstract: A surface-acoustic-wave device includes a transducer in which three transducer electrodes are provided on a non-piezoelectric or piezoelectric substrate with 0.degree., 120.degree. and 240.degree. phases, and one of the leading electrodes connected to one of the transducer electrodes extends along the surface of a piezoelectric layer provided on the substrate.

Abstract: A surface acoustic wave device in which first electrodes are provided on a piezoelectric film deposited on an elastic substrate, second electrodes between the piezoelectric film and the elastic substrate, and third electrode within the piezoelectric film, respectively, so that an electric signal is applied to the first and second electrodes.

Abstract: A surface acoustic wave device includes a silicon substrate having a main surface with a given crystalline orientation, a zinc oxide layer deposited on the main surface of the silicon substrate and a dielectric layer as well as electrodes both formed in contact with said zinc oxide layer, so that a surface acoustic wave will be propagated along a given crystalline axis direction of the silicon substrate.