Abstract: Electrically conductive thin film metallizations having continuous operating temperatures of 300° C. and more are of considerable practical interest for a number of technical applications, such as surface wave elements. Technical reasons and high production costs are a bar to the use of standard films. In order to remedy this, films including a mixture of a high-melting conductive metal and aluminum oxides, wherein in particular aluminum-rich non-stoichiometric aluminum oxides are used. The aluminum oxides act as components thermally stabilizing the conductive metal film; an optional proportion of chemically available aluminum can additionally alloy with the conductive metal and thereby enables essential film properties, such as the electrical conductivity to be specifically influenced.

Abstract: The invention relates to a measurement system for the wireless and position-independent measurement of the temperature of the load of an oven with high accuracy using passive temperature probes. The measurement system for the wireless measurement of the temperature of food or workpieces in ovens has an interrogation unit located outside the oven chamber, one or more interrogation antennas located in the oven chamber and at least one passively operated temperature probe with a probe antenna and at least one temperature sensor designed as a resonator, said temperature probe being freely movable within the oven, characterized in that the temperature sensor has at least two resonances with different temperature coefficients of frequency, wherein the electrical equivalent circuit diagrams of the resonance elements differ only slightly from each other.

Abstract: A surface wave component contains at least two interdigital transducers having natural unidirectionality, disposed on a piezoelectric crystal substrate, which form a transducer pair consisting of transmission transducer and reception transducer. The transducers consist of an interdigital electrode structure having prongs and bus bars, and have opposite forward directions. At least two of the prongs form a transducer cell that has at least one excitation center for exciting an electrical potential wave and at least one reflection center for reflection of electrical potential waves, The transducer cells consist of two prongs having the same width, having a distance between the prong centers equal to half the length of a transducer period, whereby the electrode structures of the two transducers consist of the same material, but have different layer thicknesses.

Abstract: A transducer has natural unidirectionality for surface acoustic waves. An interdigital electrode structure is arranged on a piezoelectric crystal substrate and is constructed with interdigital transducers including collecting electrodes and fingers. At least two of the fingers form a transducer cell, which includes at least one excitation center for exciting an electrical potential wave and at least one reflection center for reflecting electrical potential waves. The fingers are oriented perpendicularly to a direction R parallel to a 1- or 3-fold rotational axis of the substrate crystal and the derivative dv/d?=0 applies to R, wherein v is the phase velocity of the surface wave and ? is an angular deviation of the perpendicular to the finger direction from the direction R.

Abstract: Electrically conductive thin film metallizations having continuous operating temperatures of 300° C. and more are of considerable practical interest for a number of technical applications, such as surface wave elements. Technical reasons and high production costs are a bar to the use of standard films. In order to remedy this, films including a mixture of a high-melting conductive metal and aluminum oxides, wherein in particular aluminum-rich non-stoichiometric aluminum oxides are used. The aluminum oxides act as components thermally stabilizing the conductive metal film; an optional proportion of chemically available aluminum can additionally alloy with the conductive metal and thereby enables essential film properties, such as the electrical conductivity to be specifically influenced.

Abstract: The invention relates to a measurement system for the wireless and position-independent measurement of the temperature of the load of an oven with high accuracy using passive temperature probes. The measurement system for the wireless measurement of the temperature of food or workpieces in ovens has an interrogation unit located outside the oven chamber, one or more interrogation antennas located in the oven chamber and at least one passively operated temperature probe with a probe antenna and at least one temperature sensor designed as a resonator, said temperature probe being freely movable within the oven, characterized in that the temperature sensor has at least two resonances with different temperature coefficients of frequency, wherein the electrical equivalent circuit diagrams of the resonance elements differ only slightly from each other.

Abstract: A surface wave component contains at least two interdigital transducers having natural unidirectionality, disposed on a piezoelectric crystal substrate, which form a transducer pair consisting of transmission transducer and reception transducer. The transducers consist of an interdigital electrode structure having prongs and bus bars, and have opposite forward directions. At least two of the prongs form a transducer cell that has at least one excitation center for exciting an electrical potential wave and at least one reflection center for reflection of electrical potential waves, The transducer cells consist of two prongs having the same width, having a distance between the prong centers equal to half the length of a transducer period, whereby the electrode structures of the two transducers consist of the same material, but have different layer thicknesses.

Abstract: The invention relates to a transducer having natural unidirectionality for surface acoustic waves, wherein an interdigital electrode structure is arranged on a piezoelectric crystal substrate and is constructed with interdigital transducers comprising collecting electrodes and fingers, wherein at least two of the fingers form a transducer cell, which comprises at least one excitation center for exciting an electrical potential wave and at least one reflection center for reflecting electrical potential waves. The invention is based on the problem of finding materials, material sections, and propagation directions for transducers having natural unidirectionality that result in a low insertion loss even in broadband transducers, and for which the frequency position is not affected or is affected only slightly by errors in the orientation of the electrode structure on the substrate despite the unidirectional characteristics of the transducers.

Abstract: A transducer for surface acoustic waves, and a resonator and a filter for surface acoustic waves having the transducer are provided. The transducer for surface acoustic waves has cells containing two electrode fingers per cell, wherein the transducer exhibits unidirectional behavior for propagation directions of the surface acoustic waves parallel to highly symmetrical directions of the crystal substrate. Each of two electrodes have a plurality of electrode fingers, the electrode fingers having center axes extending parallel to their longitudinal axes and being spaced apart from center axes of adjacent electrode fingers of the same electrode by a distance which equals the ratio of the velocity of the surface acoustic wave and the cut-off frequency of the transducer. The electrode fingers of both electrodes define a plurality of cells each consisting of two fingers.

Abstract: An oscillator circuit includes a combination of two frequency-determining elements, designed as single-port surface wave resonators with interdigital converters, and one active electronic circuit. The two single-port surface wave resonators are connected to each other, avoiding inductive components. In the case of a combination in a parallel circuit, the connection is designed as a combination oscillating at high-frequency anti-resonance, and in the case of a combination in a series circuit, the combination is designed as a combination oscillating at high-frequency resonance.

Abstract: The present invention relates to a transducer for surface acoustic waves, in particular the present invention relates to a resonator and a filter for surface acoustic waves on basis of the transducer according to the present invention. The object of the present invention is to propose a transducer for surface acoustic waves which is composed of cells containing two electrode fingers per cell, wherein the transducer according to the present invention shows unidirectional behaviour for propagation directions of the surface acoustic waves parallel to highly symmetrical directions of the crystal substrate.

Abstract: The invention refers to the electrical engineering/electronics field and relates to an oscillator circuit consisting of a combination of two frequency-determining elements and one active electronic circuit, wherein the frequency-determining elements are designed as single-port surface wave resonators with interdigital converters. According to the invention, the two single-port surface wave resonators are connected to each other, avoiding inductive components whereas, in the case of a combination in a parallel circuit, the connection is designed as a combination oscillating at high-frequency anti-resonance, and in the case of a combination in a series circuit, the combination is designed as a combination oscillating at high-frequency resonance.

Abstract: A resonator filter cascade has resonator structures disposed adjacent to one another and form a waveguide for acoustic surface waves, and coupling transducers. The present invention changes resonator filter cascades so that the insertion attenuation is reduced by decreasing the attenuation of cascading, without using a coupling coil. A resonator filter cascade has resonator structures having coupling transducers which transversely couple resonator filters and the coupling transducers, belonging the same transversely coupled resonator filter, are not connected with one another. Coupling transducers of different transversely coupled resonator filters are each connected with one another over a pair of electrically conducting connections.

Abstract: The invention relates to a transverse-mode-coupled resonator filter based on surface acoustic waves. The object of the invention is to modify such resonator filters, in which there are disposed adjacent to one another on a substrate (1) a plurality of one-port resonator structures (2; 3), which comprise two strip reflectors (22 and 23; 32 and 33) and an interdigital transducer (21; 31) and together form a waveguide for surface acoustic waves, in such a way that the insertion loss of the filters is reduced, especially by reducing the damping due to the cascade connection. This object is achieved by the fact that at least one of the one-port resonator structures (2; 3) differs from the other one-port resonator structures by the ratio of the finger width to the spacing (216) of the finger centers (214; 215) and by the ratio of the width of the reflector strips (221; 231; 321; 331) to the spacing (226; 236) of the centers (224; 225 and 234; 235) of the reflector strips (221; 231; 321; 331).

Abstract: The invention relates to a resonator filter cascade on the basis of acoustic surface waves, for which at least two transversely coupled resonator filters, which are composed of several resonator structures disposed adjacent to one another and form a wave guide for acoustic surface waves, and switching transducers are present.

Abstract: The invention relates to a transverse-mode-coupled resonator filter based on surface acoustic waves.