Test standards and methods for impedance calibration of a probe system and probe systems that include the test standards and/or utilize the methods are disclosed herein. The test standards include at least one test structure. In some embodiments, the test standard further includes an alignment structure that is associated with the test structure. In some embodiments, the test standards include a plurality of test structures. In some embodiments, the plurality of test structures includes a thin film thru test structure and a thin film offset test structure. In some embodiments, the plurality of test structures is positioned to simultaneously contact a plurality of probe regions of a probe head. The methods include methods of calibrating a probe system.

A method according to the present disclosure for the controlled connection of a calibration standard in an associated calibration module to a port to be calibrated of a network analyzer connects the port to be calibrated of the network analyzer to a high-frequency port of the calibration module. It transmits a high-frequency signal generated in the network analyzer with an information signalling the calibration standard to be used to the high-frequency port of the calibration module. Within the calibration module, the information signalling the calibration standard to be used is detected from the high-frequency signal received in the calibration module, and the calibration standard to be used is connected to the high-frequency port of the calibration module by a control unit integrated in the calibration module.

A signal correction method for correcting a measured signal has the following steps: processing a digital representation of a first signal at a first measurement input; processing a digital representation of a second signal at a second measurement input corresponding to the first signal convoluted with a transfer function; and determining the transfer function for correcting the measured signal. Further, a use of the method, a system for correcting a measured signal, and an oscilloscope are provided.

An electrochemical impedance spectroscopy (EIS) current measurement system for measuring a current through a cell arrangement including one or more electrochemical cells can include a sense resistor arrangement, which can be configured to be placed in series with the cell arrangement, and voltage measurement circuitry, which can be configured to measure a voltage across the sense resistor arrangement, including to measure at least a direct current (DC) component of the voltage, where a current through the sense resistor arrangement can have a DC component and an alternating current (AC) component.

A method for selecting one or more gain values in an electrochemical impedance spectroscopy (EIS) current measurement system to provide an improved signal-to-noise characteristic can include selecting a larger one of an electrochemical cell arrangement impedance indication value and a sense resistor arrangement impedance indication value and using the selected impedance indication value as a determined impedance indication value. The method can also include determining, for a plurality of gain setting combinations, an EIS excitation current value at which current measurement circuitry of the current measurement system will reach a specified amount of a non-saturation range of the current measurement system when measuring the determined impedance indication value. The method can also include determining, for the plurality of gain setting combinations, a signal-to-noise characteristic at the determined EIS excitation current based upon a determined noise level in at least one part of the EIS current measurement system.

A calibration system for calibrating an electrochemical impedance spectroscopy (EIS) current measurement system can include a calibration resistor, which can have a specified resistance and an unspecified reactance, a reactive element which can have a specified reactance and an unspecified resistance, and a current source, which can be configured to provide a specified current through the reactive element, through the calibration resistor, and through a sense resistor arrangement of the EIS current measurement system to be calibrated, where the sense resistor arrangement can have a resistance and a reactance. The calibration system can also include voltage measurement circuitry, which can be configured to measure (1) a first voltage across the calibration resistor and a second voltage across the sense resistor arrangement and (2) a third voltage across the reactive element and a fourth voltage across the sense resistor arrangement, to determine a calibrated resistance value and a calibrated reactance value associated with the sense resistor arrangement.

A point stick module has a sensing device, a rank unit and a signal processing device. The sensing device outputs multiple sensing signals in response to operations done by a user. The rank unit provides a rank signal to represent a rank of the sensing device. The signal processing device is coupled to the sensing device and the rank unit to receive the multiple sensing signals and the rank signal, wherein the signal processing device selects a parameter according to the rank signal.

Some embodiments include a method for monitoring usage of electrical power of a structure using an electrical power monitoring system. The structure can have one or more main electrical power lines that supply the electrical power to a first load in the structure. The method can include calibrating the electrical power monitoring system. A first raw current in the one or more main electrical power lines and first calibration data can be generated while calibrating the electrical power monitoring system. The method also can include storing the first calibration data and a measurement of the first raw current. The method additionally can include measuring a second raw current. The method further can include calculating a first measured current. The method additionally can include displaying the first measured current. Other embodiments of related systems and methods are disclosed.

The present disclosure relates to a calibration unit for a vector network analyzer (VNA). The calibration unit comprises a calibration circuit which is configured to provide the calibration standards open, short and match; and an isolation circuit. The calibration circuit comprises a first port which is arranged for being connected to a port of the VNA, a second port which is arranged for being connected to a device-under-test (DUT), and a third port which is connected to a first port of the isolation circuit; and the isolation circuit comprises a second port which is arranged for being connected to one or more further calibration units.

The present disclosure provides a system and method for verifying alternating current (AC)/direct current (DC) conversion of an ultralow-frequency voltage. The system includes a quantum voltage generation system, a low-frequency signal source, a follower, three switches, a double-heater-strip thermoelectric converter, a nanovoltmeter, a clock source, a high-precision digital sampling system, and an upper computer. Based on DC and AC quantum voltage technologies and with reference to the double-heater-strip thermoelectric converter, an ultralow-frequency voltage is traced to a DC quantum voltage through AC/DC conversion, and a conversion result is compared with an AC quantum voltage to verify rationality of precision and an uncertainty evaluation result of AC/DC conversion of the ultralow-frequency voltage, so as to ensure reliability of AC/DC conversion of the ultralow-frequency voltage. This resolves a problem that the AC/DC conversion result of the ultralow-frequency voltage cannot be verified.