Fraunhofer-Gesellschaft Zur Foerderung Der Angewandten Forschung E.V.

Josef Sauerer

Hans-Peter Hohe

Norbert Weber

Stefan Moedl

Michael Hackner

Heinrich Milosiu

Frank Oehler

Johann Hauer

Elmar Herzer

Volker Peters

Ulrich Schlag

Stefan Modl

Stefan MÖDL

A capacity measuring circuit includes a measuring voltage source configured to feed a sinusoidal voltage signal to a first terminal of a capacity to be measured so as to cause a temporal change in a charge stored on the capacity to be measured. The capacity measuring circuit additionally includes a delta-sigma modulator. The delta-sigma modulator is configured to receive a charge from a second terminal of the capacity to be measured and to provide a digital output signal which is dependent on a quantity of the charge received from the capacity to be measured. The capacity measuring circuit may be employed in a sensor system.

Capacity measuring circuit, sensor system and method for measuring a capacity using a sinusoidal voltage signal

A sensor arrangement has a current regulator, a reference resistance a feed current scaler and a sensor element having an internal resistance, the internal resistance of the sensor element and the reference resistance having a predetermined ratio. The current regulator is implemented to provide a reference current by the reference resistance and to change the reference current in response to an interference influence-conditioned change of the reference resistance such that the voltage decreasing across the reference resistance remains in a predetermined range around an applied set voltage. The current regulator is implemented to provide a feed current to the feed current scaler and to change a magnitude of the feed current depending on a magnitude of the reference current. The feed current scaler is implemented to feed a scaled feed current into the sensor element to scale a voltage according to the scaling of the feed current.

Sensor arrangement and method

A method and an arrangement for magnetically determining a position using a permanent magnet are described, wherein the vector and local gradient of the magnetic flux density of the permanent magnet are measured using a position sensor, and the position and orientation of the magnetic dipole of the permanent magnet relative to the position sensor are calculated from the measured values. A spherical permanent magnet having homogenous magnetization is used in the method and the arrangement, preventing previously present cross-sensitivity between the position and orientation determination, and allowing measurement without prior calibration.

Method and arrangement for magnetically determining a position

A sensor assembly for determining a magnetization direction of an indicator magnet with respect to the sensor assembly includes a first magnetic field sensor for detecting a first and a second magnetic field component with respect to a first and a second spatial direction, and a second magnetic field sensor for detecting a third and a fourth magnetic field component with respect to the second spatial direction, wherein the first and the second magnetic field sensor are spaced apart from one another. Further, the sensor assembly includes a processor that is implemented to combine the first and the second magnetic field component to obtain a first combination quantity, to combine the third and the fourth magnetic field component to obtain a second combination quantity, to determine a position of the indicator magnet and the magnetization direction.

Sensor assembly and method for determining a magnetization direction of an indicator magnet

The invention relates to a method and a radio device for detecting a movement of at least one receiver, wherein the radio signals are sent from at least one stationary transmitter to the at least one receiver and the received signals are evaluated for determining a movement. The radio signals are designed as a specified bit sequence modulated onto a high-frequency carrier and are demodulated by the receiver to form a receiving sequence that is correlated to determine correspondence with the specified bit sequences stored as a reference sequence. Dependent on the correspondence or errors that can be determined by the correlation, quality indicators for the receiving field strength of the received radio signals are determined, wherein the radio signals having the specified bit sequence are sent from the transmitter having at least two different transmission powers in a series. The series is repeated at temporal intervals and the quality indicators of the received sequences of the series are evaluated to determine a movement of the receiver in relation to the transmitter.

Method and radio device for detecting a movement

A Hall sensor array for offset-compensated magnetic field measurement comprises a first and at least one additional pair of Hall sensor elements. Each Hall sensor element has four terminals, of which two act as power supply terminals for supplying an operating current and two act as measurement terminals for measuring a Hall voltage. Respective first supply terminals of each Hall sensor element are connected together and to a first terminal of a common voltage source and respective second supply terminals of each Hall sensor element are connected together and to a second terminal of the common voltage source so that the common voltage source supplies an operating current for the Hall sensor elements. The Hall sensor elements are operated in the spinning current mode so that the offset voltages of the Hall sensor elements approximately cancel one another out in a revolution so that the Hall signal contributions which actually depend on the magnetic field remain.

Hall sensor array for measuring a magnetic field with offset compensation

A Hall element comprises a region having a non-zero Hall constant, a first contact for supplying an operating current to the region, a third contact for conducting the operating current from the region, the first and third contacts defining a direction of the operating current within the region, a second and a fourth contact for tapping a Hall voltage, and a conductor pattern connected to the first contact or to the third contact and substantially surrounding the region laterally or being arranged above or below the region. The conductor pattern has the effect that the intrinsic field of the operating current through the Hall element is suppressed outside the Hall element such that the Hall element effects an at least reduced offset in adjacent Hall elements. In addition thereto, the arrangement of the conductor pattern has the effect that effects of the current return on the Hall voltage generated by the Hall element itself are also at least reduced. An offset reduction is possible simultaneously on an element, by way of suitable implementation, also for both operating current directions in a spinning-current operating mode.

Offset-reduced hall element

A hall sensor ( ) comprises two opposite current supply, contact electrodes ( ) between which an active area ( ) is defined for generating a current flow through the active area and two opposite voltage tapping contact electrodes ( ) for tapping-off a hall voltage, wherein a portion of the respective contact electrodes facing the active area ( ) is formed in such a way that the interfering influence of the contacts on the offset-reduced effect of the spinning current operation is reduced.

Hall sensor with a reduced offset signal

A current measuring device for measuring the current through one or a plurality of conductors (L L L ) of an array of n conductors, n being a natural number&gE;2, comprises n&plus;1 magnetic-field-sensitive sensors (S to S ) which are arranged such that two respective magnetic-field-sensitive sensors are arranged adjacent a respective conductor. A unit ( ) for reading out output signals of the magnetic-field-sensitive sensors is provided. Furthermore, the current measuring device is provided with a unit ( ) for calculating the current through one or a plurality of conductors on the basis of the read output signals and on the basis of coefficients which describe the influence of currents flowing through each of the n conductors and of a constant magnetic field on the output signal of each of the magnetic-field-sensitive sensors.

Device and method for measuring an electric current

A device for non-contractual measurement of the speed of an object moving over a surface comprises a means for radiating a signal of fixed frequency at an angle onto the surface in or against the direction of motion, said angle being variable by the movement of the object, and for receiving a Doppler-shifted signal reflected at the surface. A means is provided for combining a plurality of reflected Doppler-shifted signals, which are received in temporal succession, so as to produce a combined spectrum. The device for non-contractual speed measurement additionally comprises a means for detecting from the combined spectrum the spectral portion having the highest or lowest frequency and exceeding a predetermined signal power, and a means for deducing the speed from the frequency of the detected spectral portion.

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Herzogenaurach, Germany

Josef Sauerer