A sensor apparatus includes a sensor head and a measurement unit. The sensor head includes a first probe and a second probe. The first probe includes a first tiny antenna section for transmission and a second tiny antenna section for transmission. The second probe is arranged at a predetermined distance from the first probe, and includes a first tiny antenna section for reception and a second tiny antenna section for reception. The measurement unit generates a measurement signal that includes information regarding characteristics of a propagation of an electromagnetic wave in a medium between the first tiny antenna section for transmission and the first tiny antenna section for reception, and information regarding characteristics of the propagation of the electromagnetic wave in the medium between the second tiny antenna section for transmission and the second tiny antenna section for reception. The first probe and the second probe have different probe lengths, or a distance between the first tiny antenna section for transmission and the first tiny antenna section for reception, and a distance between the second tiny antenna section for transmission and the second tiny antenna section for reception are different from each other.

An inductive-capacitive (LC) wireless sensor for the detection of toxic heavy metal ions includes inductors and interdigitated electrodes (IDE) in planar form. The sensor may be fabricated by screen printing silver (Ag) ink onto a flexible polyethylene-terephthalate (PET) substrate to form a metallization layer. Palladium nanoparticles (Pd NP) may be drop casted onto the IDEs to form a sensing layer. The resonant frequency of the LC sensor may be remotely monitored by measuring the reflection coefficient (S.sub.11) of a detection coil (planar inductor). The resonant frequency of the LC sensor changes with varying concentrations of heavy metals such as mercury (Hg.sup.2+) and lead (Pb.sup.2+) ions. Changes in the resonant frequency may be used to detect the presence and/or concentration of heavy metal ions.

In one embodiment, a sensor arrangement for the contactless sensing of angles of rotation on a rotating part includes a disk-shaped target, a coil arrangement, and an evaluation and control unit. The disc-shaped target is coupled to the rotating part and includes at least two metal surfaces that influence the inductances in the flat detection coils due to eddy current effects as a function of the degree of overlap. The disc-shaped target can generate at least one piece of information for ascertaining the instantaneous angle of rotation of the rotating part, in connection with the coil arrangement. The coil arrangement has has three flat detection coils uniformly distributed on the circumference of a circle. The evaluation and control unit can generate essentially sinusoidal evaluation signals which represent the changes in inductance of the detection coils and can evaluate them for calculating the angle of rotation.

A coil detection circuit thereof for an electromagnetic input device including a plurality of first loop coils and second loop coils includes a first detection unit, a second detection unit and a selection unit. When the selection unit selects one the first loop coils to emit an electromagnetic signal for each one of the second loop coils, each one of the second loop coils forms a second closed loop for receiving the electromagnetic signal, and the second detection unit detects a second signal. When one of the second loop coils forms an open circuit or short circuit, the second detection unit detects an open-circuit signal or a short-circuit signal.

An inductive sensor (10) has a substrate (20), on which multiple transmitter/receiver coils (31, 32, 33) are arranged side by side. It can be operated in such a way that the transmitter/receiver coils (31, 32, 33) are each stimulated independently of one another at a frequency of more than 100 MHz.

The present invention relates to an oscillating sensor for a measurement device comprising: an oscillator comprising a resonance circuit for providing an oscillation signal; a gain stage configured to feedback to the resonance circuit to inject energy for excitation of the resonance circuit to maintain oscillation; at least one calibration element to adjust the open loop gain of the oscillator; a calibration unit to provide a modulated calibration control signal to selectively adjust an electrical measure of the at least one calibration element based on at least one predetermined duty cycle, wherein the modulated calibration control signal has an irregularly time-varying cycle frequency.

The invention relates to an oscillating sensor for a measurement device comprising: an oscillator comprising: a resonance circuit for providing an oscillation signal; a gain stage configured to provide a feed-back to the resonance circuit to inject energy for excitation of the oscillator to maintain oscillation; at least one calibration element to adjust the open loop gain of the oscillator; a calibration unit to provide a modulated calibration control signal to selectively adjust an electrical measure of the at least one calibration element based on at least one predetermined duty cycle, wherein the calibration unit is further configured to provide the modulated calibration control signal with at least one cycle frequency which depends on the oscillation frequency.

A system may include a resistive-inductive-capacitive sensor, a driver configured to drive the resistive-inductive-capacitive sensor at a driving frequency, and a measurement circuit communicatively coupled to the resistive-inductive-capacitive sensor and configured to measure phase information associated with the resistive-inductive-capacitive sensor and based on the phase information, determine a displacement of a mechanical member relative to the resistive-inductive-capacitive sensor, wherein the displacement of the mechanical member causes a change in an impedance of the resistive-inductive-capacitive sensor.

Non-contact type measuring apparatus able to detect a difference in signal intensity by transmitting a radio frequency (RF) signal having a predetermined frequency through one of two coil antennas and receiving an induced RF current signal transmitted via a medium through the other coil antennas and detect conductivity and a variation in characteristic of a non-conductor by comparing the signal intensity with a signal intensity comparison table for each frequency, which is stored in a controller by measuring a signal intensity for each frequency in advance, on the basis of the signal intensity for each frequency. The non-contact type measuring apparatus can accurately measure not only various elements using a characteristic in which conductivity is varied according to total dissolved solid, temperature, and an amount of a conductive medium and permittivity change characteristic of a non-conductor, but also conductivity and variation in characteristic of the non-conductor.

An inductive sensor (10) has a substrate (20), on which multiple transmitter/receiver coils (31, 32, 33) are arranged side by side. It can be operated in such a way that the transmitter/receiver coils (31, 32, 33) are each stimulated independently of one another at a frequency of more than 100 MHz.