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: 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: A discharge type display apparatus for displaying images through discharges in a discharge gas enclosed in discharge spaces of the apparatus. The discharge gas is a mixed gas including at least Xe, He and Ne. A mixed ratio of He to Ne in the gas mixture is set approximately for 50% in volume at most.

Abstract: It is the object of the invention to provide a structure of a novel 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 a 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: It is the object of the invention to provide a structure of a novel 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 a 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: There is provided a surface acoustic wave device for use as a filter in a television receiver set which can reduce reflection waves generated from outermost electrodes of input and output interdigital transducers to improve various filter characteristics. In the surface acoustic wave device having, on a piezoelectric substrate, the input interdigital transducer for converting an electric signal into a surface acoustic wave and the output interdigital transducer, disposed to oppose the input interdigital transducer, for converting the surface acoustic wave resulting from the conversion by the input interdigital transducer into an electric signal, a first dummy electrode is provided to a first outermost electrode finger of the output interdigital transducer, the first outermost electrode finger being located at one end of the output interdigital transducer opposite to the input interdigital transducer, and having an electrode aperture length of .lambda.

Abstract: A surface acoustic wave device makes it possible to increase the electrode width without generating mass-electrical-loading and is capable of operating in a high-frequency band higher than or equal to the UHF band, and this surface acoustic way device may be used in a communication device to eliminate need for any down-converter which is indispensable to the conventional high-frequency communication device, and which is therefore capable of being manufactured at a reduced cost. The surface acoustic wave device is provided with an electrode structure meeting conditions represented by: s+m=(2n+1)L/(4k), where L is electrode period, not taking into consideration the polarity of an interdigital transducer, m is electrode line width, s is minimum electrode gap width, and n and k are natural numbers. The surface acoustic wave device is used as the demodulator of the communication device.

Abstract: A SAW device having a piezoelectric substrate and interleaved metal electrodes formed on the substrate, in which the formation of the electrodes on the substrate is carried out by sputtering. Further, the metal electrodes may contain an additive of Cu, Ti, Zn, Mg, Fe, Ni, Cr, Ga, Ge, Sn, Pd or Ta. The resulting SAW device is capable of dealing with high frequency electric signals of a larger amplitude, or higher power electric signals, as compared with the conventional SAW device.

Abstract: A solid state electronic device having a thin film of an Al (aluminum) alloy Li (lithium) on the surface of a substrate for a surface acoustic wave (SAW). Interdigital electrodes, electric wiring patterns and bonding pads are formed by the thin film of the Li-added Al alloy. This thin film suppresses migration which occurs when a high density current is supplied to the device or a large amplitude SAW is generated. The thin film, which provides a small loss and relatively low hardness, provides a desired power handling capability and high yield of wire bonding. The this film assures high endurance to failure of the device and sufficient life of the device.

Abstract: When SAW filter is used as a receiving filter of an antenna duplexer filter in a cellular radio equipment, since a transmitting signal of an out-band frequency has a large power for the SAW filter, the large power can leak into the SAW filter to generate inter-modulation disturbances in the SAW filter. Since the inter-modulation disturbances are generated when the transmission power density of the surface acoustic wave is made too large, input converters are divided, and the divided converters are disposed in the direction perpendicular to the propagation direction of the surface acoustic wave to lower the transmission power density. Since the divided converters are connected in series, reduction in the impedence together with increase of the aperture length can be compensated.

Abstract: In a SAW device comprising a piezoelectric substrate and at least one set of metallic electrodes formed on the piezoelectric substrate, at least one set of the electrodes have a laminated structure comprised of a layer of an aluminum film added with an impurity at a concentration of 6 wt. % or less and another layer of a film of pure aluminum or aluminum added with an impurity at a concentration of 0.4 wt. % or less. The SAW device having the laminated structure of electrodes can handle high frequency electric signals of higher power and/or larger amplitudes.

Abstract: In an elastic surface wave device comprising a piezoelectric substrate, a first transducer group, and a second transducer group or groups located on one or both sides of the first transducer group to exchange elastic surface waves with the first transducer group, the second transducer group comprises a plurality of transducers sharing the same elastic surface wave propagation path. The geometrical central positions of the individual transducers making up the second transducer group are located symmetrically about the geometrical central position (0--0') of the entire second transducer group, with each pair of such symmetrically located transducers incorporating the same number of pairs. The delay time, that is, the time taken by elastic surface waves propagating between the centers of every two adjoining transducers, excluding the two outermost transducers, is constant (.tau.).

Abstract: A surface acoustic wave (SAW) device comprises a piezo-electric surface acoustic substrate, and plural sets of input/output interdigital electrodes disposed on the substrate. A phase shifter is provided between a sending electrode and a reflecting electrode included in the input or output interdigital electrodes for producing an electrical phase difference to implement a unidirectional electrode. The sending electrode and the reflecting electrode are mutually connected through the phase shifter including two pure reactance elements serially connected between the sending and the reflecting electrodes and a pure reactance element connected to the junction between the two serially connected reactance elements so as to form a T-circuit. When the two serially connected pure reactance elements are selected equal to each other, the operating frequency band is broadened. The phase shifter includes no ohmic resistance and thus is lossless.

Abstract: In an apparatus for descrambling a scrambled television signal, an elastic surface wave filter is used. This elastic surface wave filter has an interdigital electrode having an electrode pattern similar to at least portion of the waveforms of a luminance signal section of the scrambled television signal to be input. The elastic surface wave filter generates a response pulse only when the waveforms which are analogous to the electrode pattern of the interdigital electrode of the scrambled television signal were input, thereby descrambling the television signal using this response pulse.

Abstract: An elastic surface wave device that has good frequency characteristics and no unwanted signals, and is highly suited for mass production, comprising a piezoelectric substrate, at least one pair of transmitting and receiving electrodes on the surface of said substrate, and elastic surface wave absorbers formed by curing a composition, the main component of which is a resin curable by ultraviolet radiation, disposed on at least part of the zone on said piezoelectric substrate that propagates unwanted elastic surface waves.

Abstract: Disclosed is a surface acoustic wave transmission device comprising a piezoelectric substrate provided thereon with an input and output transducers for transmitting and receiving the surface acoustic wave, a package for accommodating the piezoelectric substrate, and an adhesion layer for fixing the bottom of the piezoelectric substrate to the ground plane of the package. The adhesion layer is made to have a thickness of .lambda..sub.R /2.6 or more wherein .lambda..sub.R : is the wave length of the surface acoustic wave at the main lobe of the operating frequency, so that unnecessary waves caused by bulk wave components are absorbed.

Abstract: A surface acoustic wave device, a method for manufacturing the same and a manufacturing equipment therefor are disclosed. In the surface acoustic wave device having functional elements such as input and output interdigital electrodes of Al, Al-Si alloy or Al-Cu-Si alloy thin film strips and a grating type reflector, arranged on a piezoelectric substrate and any other bus conductors arranged on the same substrate, at least a portion of the functional elements and the bus conductors having a high frequency metal strip having a line width of no more than 2 .mu.m, at least the metal strip having the width of no more than 2 .mu.m has a film thickness of no less than 0.25 .mu.

Abstract: In a preferred embodiment, a surface acoustic wave device comprises a piezoelectric substrate, a first electrode formed on the substrate and acting to convert an electrical signal into a surface acoustic wave, and second and third electrodes formed on the substrate and acting to convert the surface acoustic wave into an electrical signal. The second and third electrodes are disposed at different distances from the first electrode and connected electrically with each other. Electrode fingers of the second electrode are arranged in a relationship of the opposite polarity with respect to those of the third electrode so as to cause peaks in the constant frequency interval multi-peak frequency characteristics of the device acting as a filter to take place at frequencies which are (integer+1/2) times the constant frequency interval .DELTA.f. In another preferred embodiment, a plurality of surface acoustic wave device units are formed on a common piezoelectric substrate.

Abstract: A surface-acoustic-wave filter for a channel selection tuning system of a television receiver includes at least two comb filter elements, each of which comprises an input transducer provided on a piezoelectric substrate and adapted to convert an input electrical signal into an elastic surface wave, and first and second output transducers disposed on the substrate for receiving the elastic surface wave propagating in the same direction from the input transducer. The first and second output transducers are positioned from the input transducer with different distances. The transducers of the two comb filter elements are so designed that the respective comb filter elements respond to frequencies of different program channel bands over for example VHF and UHF bands.