Abstract: A micro total analysis system, operating method and manufacturing method thereof are provided. The micro total analysis system includes at least one micro total analysis unit each including: microfluidic device including first electrode and dielectric layer connected to each other, where the dielectric layer drives to-be-measured droplet to move based on voltage of the first electrode; and acoustic wave detection device including second electrode connected to the dielectric layer, where the dielectric layer is also used as transducer of the acoustic wave detection device, and configured to generate acoustic wave toward the droplet based on voltage of the second electrode, and generate a detection result corresponding to the droplet based on received acoustic wave. The micro total analysis system, the operating method and the manufacturing method thereof enables the microfluidic device and the acoustic wave detection device to be integrated in the same chip.

Abstract: A weather-detecting device (100) can include a substrate (102) and a detection region (106) exposed to an environment within which the weather-detecting device (100) is situated when in use. An array (110) of heating elements (112) can be mounted at a first side of the substrate (102), with at least one surface of each heating element (112) in the array (110) being positioned within the detection region (106). A controller can be electrically coupled to the array (110) of heating elements (112), and the controller can individually address each heating element (112) in the array (110) to selectively pass electrical current through each heating element (112).

Abstract: Devices and methods for the detection of streams of water or other extinguishants. A device has a substrate, an array including a plurality of capacitance sensors disposed on the substrate, and a controller operatively connected to each of the plurality of capacitance sensors to measure a capacitance of each respective sensor. The controller is configured to analyze a time-varying component of a series of measured capacitances for each sensor and to output a signal representing how closely that time-varying component matches a stored reference component of a reference signal in which a sensor is proximate to a stream of an extinguishant. A corresponding method obtains a series of measured capacitances from each of a plurality of capacitance sensors disposed upon a substrate, analyzes a time-varying component of the each of the series, and outputs a signal representing a degree of similarity between that series and such a reference signal.

Abstract: A threaded fluidic fitting may include a fluid passage, at least one fluid port, a threaded fitting portion, an engageable body portion, and an electro-fluidic leak detection element. The fluid passage extends from the fluid port of the threaded fluidic fitting. The threaded fitting portion comprises a helical thread, extends from a leak detection face of the engageable body portion, and is configured to rotate with the engageable body portion to enhance a fluidically sealed engagement of one of the fluid ports with a complementary fluidic component. The electro-fluidic leak detection element is positioned on the leak detection face of the engageable body portion or on a drip edge portion of a face extending from the leak detection face. A fluid handling system may include a plurality of threaded fluidic fittings and a leak detecting computing hub in communication with the plurality of threaded fluidic fittings.

Abstract: A system may include a controller configured to cause a capacitance probe to subject a material to a first electric signal having a first frequency and determine a first capacitance of the material at the first frequency. The controller is configured to cause the capacitance probe to subject the material to a second electric signal at a second frequency and determine a second capacitance of the material at the second frequency. The material includes at least a first constituent phase and a second constituent phase. The first constituent phase and the second constituent phase have substantially similar dielectric constants at the first frequency and substantially different dielectric constants at the second frequency. The controller is further configured to determine a porosity of the material based on the first capacitance and determine a relative phase composition of the first constituent phase and the second constituent phase based on the second capacitance.

Abstract: An electrical device including: voltage carrying components, a solid insulation system configured to electrically insulate the voltage carrying components, and a moisture sensor configured to detect moisture in the solid insulation system, wherein the moisture sensor includes: a capacitor having: a first electrode, a second electrode, and a dielectric material arranged between the first electrode and the second electrode, wherein the solid insulation system forms the dielectric material, the capacitance of the capacitor providing an indication of a moisture level in the dielectric material.

Abstract: An arrangement for determining the moisture of an object, in particular the moisture of human skin, has an electrically insulating carrier layer onto which the following units are applied: at least two electrodes, in particular interdigital electrodes, which are arranged on a first face of the carrier layer; a digital capacitance measuring device, to which the electrodes are connected; an NFC transponder which comprises an antenna and to which the measurement results of the capacitance measuring device are supplied in order to be forwarded wirelessly via the antenna, wherein the NFC transponder and the capacitance measuring device are arranged in the same chip in particular; and a shielding, which lies on the carrier layer face opposite the first face and which is connected to system ground of the capacitance measuring device in particular.

Abstract: A measurement device (10) comprising a sensing circuit (30) which is electrically floating and fully isolated. The sensing circuit (30) has a first (134) and a second (148) transformer across which is connected a measurement circuit (110). The device is so constructed that any signal generated in the coil (132) of the said first transformer (134) that is connected to the measurement circuit (110) caused by a change in any external magnetic field relative to the measurement circuit (110) is in anti-phase with the corresponding signal generated in the coil (164) of the said second transformer (148) that is connected to the measurement circuit (110).

Abstract: A system and method for providing optimal irrigation or watering, and more specifically providing a soil sensor grid placed in the ground of a landscaped property, in commercial, residential or even agricultural areas. The soil sensor grid can allow for optimal water usage in a specified irrigation area by providing real time data to an irrigation system and a user to optimize water usage. A soil sensor grid, or moisture sensor grid, may be installed on a property, buried in the ground, to provide current and real time feedback of the current moisture levels of the soil. The moisture data is uploaded to the cloud and provided to a user and the irrigation system allowing a user to automatically or manually manipulate the irrigation system to properly water or irrigate different portions of the property based on the data from the soil sensor grid.

Abstract: The present invention discloses a novel capacitive vapor sensor comprising porous immobilized graphene oxide (pGO) on an electrode surface. Also disclosed is an in-situ process for the preparation of this sensor and various uses thereof.

Abstract: A capacitance measurement circuit for determining a sense current of a capacitive sensor with a sense electrode and a guard electrode. The measurement circuit includes a periodic signal voltage source, a sense current measurement circuit configured for determining the sense current with reference to a reference voltage, and at least one remotely controllable switch member. In a first switching state, the at least one switch member electrically connects the sense current measurement circuit to the periodic signal voltage source for providing a first reference voltage, and in a second switching state, the at least one switch member electrically connects the sense current measurement circuit to a second reference voltage that is different from the first reference voltage.

Abstract: A system and method for imaging, monitoring, or measuring systems and processes utilizing only data provided from capacitance sensors. The present invention combines the multi-frequency method of both ECVT/AECVT and DCPT to image or measure processes and systems more efficiently and accurately than the methods alone. The present system analyzes capacitance and current phase acquired at multiple frequencies to determine a plurality of properties of single and multiphase systems all at once. The combined use of ECVT and DCPT in multiphase flow can also be extended to measure volume fraction and phase distribution of flows involving greater than three phases by using multiple frequencies for capacitance, current phase, or both.

Abstract: Soil moisture monitoring systems and methods for measuring mutual inductance of area of influence using radio frequency stimulus are disclosed herein. An example method includes receiving a first inductance frequency sample from a first oscillator circuit, the first oscillator circuit being coupled with one or more reference inductors; receiving a second inductance frequency sample from a second oscillator circuit, the second oscillator circuit being coupled with one or more mutual inductors that sense soil moisture inductance in an area of soil; receiving a temperature reading from a thermometer, the temperature reading being obtained when the first inductance frequency sample and the second inductance frequency sample were obtained. The example method further includes transmitting the first inductance frequency sample, the second inductance frequency sample, and the temperature reading to a receiver.

Abstract: A system and method for imaging, monitoring, or measuring systems and processes utilizing only data provided from capacitance sensors. The present invention combines the multi-frequency method of both ECVT/AECVT and DCPT to image or measure processes and systems more efficiently and accurately than the methods alone. The present system analyzes capacitance and current phase acquired at multiple frequencies to determine a plurality of properties of single and multiphase systems all at once. The combined use of ECVT and DCPT in multiphase flow can also be extended to measure volume fraction and phase distribution of flows involving greater than three phases by using multiple frequencies for capacitance, current phase, or both.

Abstract: A pane arrangement having a pane with an inner surface and an outer surface, a low-E coating arranged on the inner surface of the pane. The pane arrangement having a coating-free first partition line formed in the low-E coating. A capacitive switching region is electrically isolated from a surrounding region of the low-E coating. The surrounding region surrounds the capacitive switching region in sections. The capacitive switching region has a contact region, a supply line region and a first connection region. The supply line region electrically connects the contact region to the first connection region. A coating-free second partition line is formed in the low-E coating. The surrounding region is electrically isolated from an outer region of the low-E coating. The outer region surrounds the surrounding region. A capacitive sensor electronics system is electrically connected to the first connection region of the capacitive switching region and to the surrounding region by a second connection region.

Abstract: The field is sensors used in the ground and in particular the provision of a sensor array element for a sensor array useable in housing that has a tapered internal and external shape. The lack of air spaces and gaps, in particular, between the outer surface of the hollow elongate sensor housing and the surrounding ground is substantially avoided when using a tapered housing. A sensor array element is disclosed including a carrier sheet of flexible material formable into a shape which substantially conforms with the shape of the inner wall of said elongate housing. The carrier sheet has electrically conductive regions wherein at least one pair of electrically conductive regions are shaped and located near enough each other to form a capacitive element. The carrier sheet has at least two pairs of electrically conductive regions forming a pair of capacitive elements, and adjacent pairs of capacitive elements have a different diameter.

Abstract: A fuel filter may include a housing and a filter element positioned within the housing. A water collection chamber may be defined in the housing and may be constructed and arranged to collect water separated from a fuel. A water level sensor may be positioned within the water collection chamber. The water level sensor may be constructed and arranged to detect a water level in the water collection chamber. The water level sensor may include an electrically conductive plastic first terminal.

Abstract: A laminated glazing including a moisture-sensitive functional insert included within the glazing, the laminated glazing comprising a stack comprised of a plurality of glass or plastic plies, the plies being joined together by interlayers located between the plies, wherein a central area of the stack comprises at least one optically clear interlayer; the stack further including a moisture-sensitive functional insert; wherein an inner perimeter of the laminated glazing is formed with a frame comprised of a hydrophobic moisture-resistant material, the frame having a thickness substantially corresponding to a combined thickness of the interlayers within the glazing plus the insert. In addition, a method of reducing or eliminating exposure of a moisture-sensitive insert within a laminated glazing constructed as above is also described herein.

Abstract: A sensor housing having a body for housing a soil moisture sensor arrangement with sensors arranged within and along the length of the housing, the body is shaped so that there is a continuous taper from the head end having the larger outer diameter to the inserted end having the smaller outer diameter, and the volume of the opening created by an auger in the ground will provide a matching volume for the sensor housing of a predetermined volume such that the entire tapered outer surface of the sensor is adjacent the ground along the full length of the created opening. The sensors include at least a first capacitive element, and a second capacitive element that has a maximum outer diameter smaller than the maximum outer diameter of the first capacitive element.

Abstract: An electronic circuit can be coupled to an energy harvesting device. The output of the energy harvesting device can provide a damped oscillating waveform elicited from a transient stimulus applied to the energy harvesting device, such as in response to mechanical shock or mechanical impact excitation. A first switch can be coupled between the energy harvesting device and an inductor and configured to selectively connect the input node to the inductor. A second switch can be coupled between the inductor and an energy storage device, the second switch configured to selectively couple the inductor to the energy storage device. A control circuit can be coupled to the first and second switches, such as configured to operate the first and second switches according to one or more of an over bias flip technique, a half bias flip technique, or a bias flip technique.

Abstract: A transparency, e.g. an aircraft laminated windshield, includes one or more moisture sensors to monitor moisture penetration to monitor performance of the moisture barrier. At least one of the moisture sensors includes a dielectric between and in electrical contact with two electrically conductive electrodes. Alternating electrical current is applied to the electrodes to measure the complex impedance (ohms) of the dielectric to determine the amount of moisture within the laminated windshield in the area of the moisture sensor. With the information provided by the moisture sensors performance of the windshield is available to schedule timely repair or replacement of the windshield that is performing outside of acceptable limits.

Abstract: A system for monitoring the characteristics of a material by measuring electrical properties of a material uses a material monitoring device and a cloud database that relates electrical properties of a material to characteristics of that material. The aging and fermentation processes of wine and other alcohols can be monitored. The status and decomposition of foodstuffs can be monitored. The progress of chemical reactions in a vessel can be monitored. Water quality of water from a water conduit can be monitored. These characteristics can be indicated on a product monitoring device or can be communicated to an external computing device.

Abstract: An example approach and structure for providing a chemical sensor, having an electrode that may receive a fluid that is passed on towards a dielectric between the electrode and one or more other electrodes. A capacitance between the electrodes may be changed by the dielectric which is affected by a parameter of the fluid. Measuring a change of the capacitance may indicate a magnitude of the parameter. The electrode receiving the fluid may have one or more layers of metal particles that by design of the particles and their arrangement can result in determined pore sizes and routes through the electrode for a controllable porosity of the electrode.

Abstract: The invention pertains to an apparatus and a method for determining a dielectric property of a first substance in a composition in a non-invasive manner. The composition includes at least the first substance to be measured and a second substance. The method uses and apparatus includes a capacitor for creating a field into which the composition can be introduced at least in part, where the capacitor is part of an oscillator circuit, and the oscillator circuit is coupled to a device for determining the resonance frequency of the oscillator circuit. The capacitor includes a layer of a non-conducting material such that the composition, when introduced at least in part into the field of the capacitor, does not come into an electrical contact with the electrodes of the capacitor.

Abstract: A multimodal sensor includes a microtensiometer for measuring the chemical potential of a sub-saturated liquid, a temperature sensor, and a water content sensor. The microtensiometer includes a sensor body comprising a first gas-impermeable layer, an opposing second gas-impermeable layer, and a porous membrane layer disposed therebetween. The sensor body defines an internal liquid reservoir. The membrane layer is fluidly connected with the liquid reservoir, and extends to an outside edge of the microtensiometer. The membrane layer defines a plurality of through pores providing an open path from the liquid reservoir to the outside edge of the microtensiometer. The pores have a maximum diameter of 3 millimeters. The microtensiometer further includes a sensor adapted to measure changes in pressure between the liquid reservoir and an outside environment. The temperature sensor is integrated onto the microtensiometer body, and the water content sensor is coupled to the microtensiometer body.

Abstract: A plate heat exchanger includes a heat exchanger plate having a heat transfer area and an edge area, extending around the heat transfer area. The heat exchanger plate is a double wall plate formed by two adjoining plates compressed to be in contact with each other. A sensor configured to sense at least one parameter and to produce a signal depending on the parameter includes a sensor probe that is provided between the adjoining plates.

Abstract: A fluid detection apparatus and a fluid detection method are provided. The fluid detection apparatus includes a plurality of capacitive detection units and a sensing circuit. The capacitive detection units are sequentially arranged along a detection direction, wherein each of the capacitive detection units generates an impedance variation in response to the submergence of the fluid and accordingly generates a corresponding fluid detection signal. The sensing circuit is coupled to the capacitive detection units so as to receive the fluid detection signals and send a first status indication signal indicating a spread circumstance of the fluid along the detection direction according to the fluid detection signals.

Abstract: A capacitance detection circuit has at least a carrier signal generating circuit that supplies a carrier signal to one of a movable or a fixed electrode of a sensor, an operational amplifier with one of the movable or fixed electrode as an input and ground as another input, and a printed circuit board on which the physical quantity sensor, the carrier signal generating circuit, and the operational amplifier are mounted. An insulation-secured area on the printed circuit board is configured as a moisture absorption reduction area, including at least an electrode connection part of the physical quantity sensor, an input-side connection part of the operational amplifier, and a connection part connected to the input side of the operational amplifier out of connection parts of input-side circuit components connected between the electrode connection part and the input-side connection part.

Abstract: The present invention is systems and methods for detecting and locating leaks in roofing membranes and roof flashing. The systems include a conductive mesh underneath the roofing membrane and/or a conductive medium behind the roof flashing; attractor cables; and a reversible power supply attached to the conductive mesh/medium and attractor cables. The roofing membrane system also includes sensors, which may be wireless. The systems are controlled by a computer.

Abstract: The present invention is systems and methods for detecting and locating leaks in roofing membranes and roof flashing. The systems include a conductive mesh underneath the roofing membrane and/or a conductive medium behind the roof flashing; attractor cables; and a reversible power supply attached to the conductive mesh/medium and attractor cables. The roofing membrane system also includes sensors, which may be wireless. The systems are controlled by a computer.

Abstract: The present invention is a method and system for detecting and locating leaks in a roofing membrane. The mean net voltage from an emitting electrode activated by and connected to the positive side of a power supply, when a conductive mesh disposed beneath the membrane is connected to the negative side of the power supply, is compared with the mean reference voltage from the emitting electrode when a reference electrode is connected to the negative side of the power supply in place of the conductive mesh. If the mean net voltage is greater than or equal to the mean reference voltage, then a leak is indicated.

Abstract: A water vapor sensor comprises a substrate and a film of carbon nanotubes impregnated with surfactant on the substrate. The substrate is of material which is inert relative to the film. Two or more electrical conductors are in contact with in spaced apart zones of the film, whereby the impedance of the film may be measured. The sensor is housed in housing which protects the sensor but also allows exposure of the film to water vapor.

Abstract: An object of the present invention is to provide a moisture measuring apparatus which, when the body of the apparatus for measuring a state of moisture in a measurement target object is mounted into the measurement target object, provides a user with a mounting state as to whether the moisture measuring apparatus has been appropriately mounted. In the present invention, the CPU of a moisture measuring apparatus determines the mounting state of the moisture measuring apparatus in soil that is a measurement target object (judges whether or not there is a gap between a sensor electrode and soil) based on the state of moisture (moisture amount) measured by a soil moisture amount sensor, and informs a result of the judgment.

Abstract: The invention relates to a device, system and method for measuring moisture in building structures. A tubular body part (100) may be embedded in a material during its casting. Hole(s) (106) provided in the body part (100) lets moisture inside a space separated by the body part (100). Measuring element including electronics (102) and a sensor (104) functionally connected to the body part (100) is used to measure the separated space 108. With a reading device (234), the results may then be read from above surface due to a provided wireless link between the measuring element (102) and (104) and the reading device (234).

Abstract: Electrically conductive structures produced on or in a substrate, or produced such that the structures are floating in a substrate undergo simple and reliable capacitive contactless and non-destructive inspection using a capacitive sensor having at least two sensor electrode surfaces which are arranged at different constant distances from one another parallel to a surface of the substrate and are arranged beside one another relative to the surface of the substrate.

Abstract: A method for providing corrected measurements of absolute capacitance of an object in the proximity of at least two independent electrodes of a non-optimized shape integrated in a human-machine interface device for detecting the object. The method includes measuring, for each electrode, an actual value of absolute capacitance between the electrode and the object, and calculating a prediction by applying a multi-variable nonlinear prediction model to the actual values of absolute capacitance so as to obtain an image of probability densities. Then, using the probability densities as corrected absolute capacitance values for detecting the object.

Abstract: An interconnect structure and method of fabricating the same is provided. More specifically, the interconnect structure is a defect free capped interconnect structure. The structure includes a conductive material formed in a trench of a planarized dielectric layer which is devoid of cap material. The structure further includes the cap material formed on the conductive material to prevent migration. The method of forming a structure includes selectively depositing a sacrificial material over a dielectric material and providing a metal capping layer over a conductive layer within a trench of the dielectric material. The method further includes removing the sacrificial material with any unwanted deposited or nucleated metal capping layer thereon.

Abstract: A method of operating a sensor 112 having a first transmit plate 114, a second receive plate 115 and a dielectric material between the two plates 114, 115. The method comprises the steps of: applying an alternating across the transmit and receive plates 114, 115, thereby to create an alternating electric field, which applied voltage results in a current Iz flowing through the two plates 114, 115; producing a voltage signal corresponding to the resultant current Iz; determining the average value of the product of the corresponding voltage signal and a reference voltage signal Vref3; and adjusting the phase of the reference voltage Vref3 until a null condition is achieved, at which condition the average value is approximately zero. A sensor 112 is also disclosed.

Abstract: In one aspect the present invention provides a down-hole monitoring system, comprising one or more pieces of down-hole equipment, for example a down-hole logging tool, and at least one resonant sensor for obtaining physical and chemical parameters of a down-hole fluid in proximity to the sensor. In another aspect, the present invention provides a method for detecting material properties of a down-hole fluid, the method comprising placing a resonant LCR sensor within a piece of down-hole equipment, taking sensor readings down-hole, transmitting the sensor readings to a reader device, and analyzing the sensor readings.

Abstract: A controller is coupled to a plurality of moisture sensors positioned within the grain bin at various spaced-apart locations. The controller determines a grain moisture level adjacent each moisture sensor and compares the grain moisture level to a predetermined maximum moisture level. The controller is coupled to a grain spreader that is configured to selectively distribute incoming grain into the grain bin and operates the spreader to distribute incoming grain to create a shortened airflow path through the grain that encompasses the moisture sensors having determined grain moisture levels above the predetermined maximum moisture level. The controller is coupled to a fan that is coupled to the grain bin and configured to provide airflow through the grain in the grain bin. The controller operates the fan to provide greater airflow through the grain along the shortened airflow path than is provided along airflow paths outside the shortened airflow path.

Abstract: A moisture sensor includes a first electrode, a layer of porous insulating material including a plurality of pores, a film of dielectric sensing material covering the inner surfaces of the plurality of pores and a second electrode.

Abstract: A moisture sensor unit for sending moisture in an environment includes a passive moisture sensor and two passive RFID tags. The two passive RFID tags are spaced apart from each other and disposed on opposite sides of the moisture sensor. Each of the RFID tags is electrically coupled to the moisture sensor and each of the RFID tags includes a circuit that determines an amount of moisture that is associated with the moisture sensor. Each of the RFID tags is configured to respond to a first radio frequency signal with a second radio frequency signal that includes information about the amount of moisture.

Abstract: A method, circuit and apparatus for detecting capacitance on a droplet actuator, inter alia, for determining the presence, partial presence or absence of a droplet at an electrode on a droplet actuator by: (a) providing a droplet actuator comprising: (i) a substrate comprising electrodes arranged on the substrate for conducting droplet operations on a surface of the substrate; (ii) a capacitance detection circuit for detecting capacitance at the droplet operations surface at one or more of the electrodes; (b) detecting capacitance at the droplet operations surface at one or more of the electrodes; and (c) determining from the capacitance the presence, partial presence or absence of a droplet at the droplet operations surface at the electrode.

Abstract: A method and system for monitoring the dynamic response of soil moisture and setting a threshold in relation to the field capacity of a soil area is disclosed herein. By measuring the dynamic response of soil moisture under wet soil conditions, one can determine a practical field capacity for the soil, in-situ, based solely on the soil moisture sensor output. Essentially, by looking at how the soil moisture level varies with time one can determine the field capacity.

Abstract: A method and apparatus for transmitting a measurement variable that is detected by a measuring unit and transmitted via a data transmission channel to a main control unit of a domestic appliance that is isolated from the measuring unit is disclosed. The measurement control unit is coupled to the main control unit via a data transmission channel through which a measurement variable detectable by the measuring unit can be transmitted to the main control unit. The data transmission channel is a line having a protective impedance.

Abstract: The invention relates to devices for liquid level detection (LLD). It relates to a laboratory device having an electronic circuit for detecting a liquid level in a liquid container, a feeler, which can be advanced, and which is connected to an input side of the electronic circuit, and having a movement device, which allows the feeler to be advanced in the direction of the liquid in the liquid container. Upon the immersion of the feeler in the liquid, a capacitance change is caused in the electronic circuit, which triggers a signal in the circuit. The laboratory device comprises a reference circuit, which is connected to the input side of the circuit, and which specifies an effective capacitance on the input side of the circuit. A sequence controller is used, which causes the triggering of a test by the application of a control signal to the reference circuit, the control signal causing an increase of the effective capacitance through a switching procedure.

Abstract: A system for measuring crop moisture content in a harvester elevator includes a receiver and processing node and one or more moisture sensing instruments coupled to one or more paddles of the harvested elevator, respectively. The moisture sensing instruments each include a moisture sensor and a transmitter in communication with a receiver and processing node. The moisture sensor is configured to dynamically measure the moisture content of a static harvested crop, relative to the sensor and corresponding paddle, at ascends in the harvester elevator.

Abstract: Electronic devices may be accidentally exposed to liquid during operation. To detect liquid intrusion events, an electronic device may be provided with one or more electronic liquid contact sensors. The liquid contact sensors may have electrodes. Control circuitry may make measurements across the electrodes such as resistance and capacitance measurements to detect the presence of liquid. Liquid contact sensor data may be maintained in a log within storage in the electronic device. The liquid contact sensor data can be used to display information for a user of the electronic device or can be loaded onto external equipment for analysis. Liquid contact sensor electrodes may be formed from metal traces on substrates such as printed circuits, from contacts in a connector, from contacts on an integrated circuit, or from other conductive electrode structures.

Abstract: An apparatus including a sensor array, configured to produce an array output value in response to an environmental stimulus, and a controller, the sensor array including a plurality of sensors and a common output terminal connected to the respective outputs of the sensors, each sensor having first and second electrodes configured to output a respective sensor output value in a particular environment based on the areas of the first and second electrodes and/or the spacing therebetween, the controller configured to control which of the sensors are connected to the common output terminal using respective switches to vary the effective area and/or spacing of the sensor array such that the array output value at the common output terminal, based on the contribution of the respective sensor output values of the connected sensors, is held at a reference value.

Abstract: The invention relates to a method for determining a level of a material interface in a tank, by means of a radar level gauge system comprising a transceiver; a probe for guiding a transmitted electromagnetic signal towards the material interface. The probe comprises a first plurality of reference impedance transitions located above the interface at known physical distances from a reference position, and a second plurality of reference impedance transitions located below the interface at known physical distances from the reference position. The method comprising determining electrical distances to the first and second plurality of reference impedance transitions based on a signal reflected by the reference impedance transition, determining, a first and a second approximation function relating the first and second sets of electrical distance values to the physical distances; and determining the level of the material interface based on the first approximation function and the second approximation function.