A calibration apparatus calibrates cross-frequency phases of large-signal network analyzer measurements and includes: a signal generator; a vector network analyzer that includes couplers and receivers that receive the calibration signal and the reference multitone signal from the signal generator; a calibration receiver that receives a calibration signal from the vector network analyzer and produces a digitized calibration temporal signal from the calibration signal; and a signal processor in communication with the signal generator and the vector network analyzer and that: receives the reference digitized signal from the reference receiver; receives the forward digitized signal from the forward coupled receiver; receives the reverse digitized signal from the reverse coupled receiver; receives the digitized calibration temporal signal from the calibration receiver; and produces a calibration factor from the reference digitized signal, the forward digitized signal, the reverse digitized signal, and the digitized calibration temporal signal.

A capacitive sensor includes a first conductive structure; a second conductive structure that is counter to the first conductive structure, wherein the second conductive structure is movable relative to the first conductive structure in response to an external force acting thereon, wherein the second conductive structure is capacitively coupled to the first conductive structure to form a first capacitor having a first capacitance that changes with a change in a distance between the first conductive structure and second conductive structure; a signal generator configured to apply a first electrical signal step at an input or at an output of the first capacitor to induce a first voltage transient response at the output of first capacitor; and a diagnostic circuit configured to detect a fault in the capacitive sensor by measuring a first time constant of the first voltage transient response and detecting the fault based on the first time constant.

A capacitive sensor includes a first conductive structure; a second conductive structure that is counter to the first conductive structure, wherein the second conductive structure is movable relative to the first conductive structure in response to an external force acting thereon, wherein the second conductive structure is capacitively coupled to the first conductive structure to form a first capacitor having a first capacitance that changes with a change in a distance between the first conductive structure and second conductive structure; a signal generator configured to apply a first electrical signal step at an input or at an output of the first capacitor to induce a first voltage transient response at the output of first capacitor; and a diagnostic circuit configured to detect a fault in the capacitive sensor by measuring a first time constant of the first voltage transient response and detecting the fault based on the first time constant.

A temperature test apparatus 1 includes a test antenna 6 configured to transmit or receive a radio signal to or from the antennas 110 in order to measure reception characteristics or transmission characteristics of the DUT 100, a heat-insulating housing 70 made of heat-insulating material surrounding a space region 71 including a quiet zone QZ, and a measuring device 20 configured to measure the transmission characteristics or the reception characteristics of the DUT 100. The heat-insulating housing 70 has a flat plate shaped part 70a in a region through which radio waves of a radio signal transmitted from the test antenna 6 passes before entering the quiet zone QZ. The flat plate shaped part 70a is perpendicular to the traveling direction of the radio waves of the radio signal entering the quiet zone QZ.

The focus of the teachings is on using Compact ferrite antenna to detect the motion of metal objects using a very low frequency (VLF) square wave, propagated between a pair of compact ferrite-particle dielectric-core RWA antennas in free space. The two salient features in the signal are observed; both of which are characteristic of Brillouin-precursor propagation: (1) a temporal Bessel-like waveform; and (2) an algebraic, rather than exponential, attenuation with distance over three meters. The key element teaching shows pair of source and detector antenna enables the detection of metals (weapon gun, knife) on a person or package between the ferrite- particle dielectric-core antennas- source (S) and detector (D) pairs or arrays of S-D tractor. The detection consisted of a change in the amplitude of the Bessel-like waveform of the received signal for security system to detect weapons.

Measurement of signal power for variable or time varying signals. A log-linear VGA coupled in a feedback configuration to a difference detector and an integrator, includes a set of amplifier cells selectable by a sliding current generator, producing a sum of outputs. Outputs of the sliding current generator include a first control current provided using a sum of amplified currents, a sequence of intermediate control currents, and a final control current provided using a sum of amplified currents. Control currents to be summed can be differentially amplified or attenuated; attenuators include capacitors to compensate for capacitive loading. Selectable amplifier cells are differentially amplified or attenuated. Isolating switches and canceling stages reduce the effects of leakage between adjacent amplifier cells. The sliding current generator can have boosted current to first and last amplifier cells, providing a more linear-in-dB gain near a relative maximum or minimum.

A method and apparatus are for monitoring a secondary power device and for accurately checking a state of the secondary power device, and an electronic system includes the apparatus. The method of monitoring a secondary power device includes setting a first reference parameter by using a voltage of at least one capacitor of the secondary power device, setting a second reference parameter by using the voltage of the at least one capacitor and the first reference parameter, and setting a reference level for checking of the state of the secondary power device by using the second reference parameter, wherein the reference level is used in checking of the state of the secondary power device.

A method and apparatus are for monitoring a secondary power device and for accurately checking a state of the secondary power device, and an electronic system includes the apparatus. The method of monitoring a secondary power device includes setting a first reference parameter by using a voltage of at least one capacitor of the secondary power device, setting a second reference parameter by using the voltage of the at least one capacitor and the first reference parameter, and setting a reference level for checking of the state of the secondary power device by using the second reference parameter, wherein the reference level is used in checking of the state of the secondary power device.

A method for the correction of synchronization errors Δt in the measurement of the impedance of an electrical or electrochemical component, more particularly a lithium ion cell is provided. In general, synchronization errors in an impedance measurement can arise between the excitation and response signals, which can misrepresent the phase of the impedance value obtained. According to the method, the synchronization error can be determined by measuring the impedance at two different frequencies and solving an optimization problem in respect of the deviation of the phases from an equivalent circuit diagram, which comprises at least one resistance and an inductance. The phase of the impedance value obtained can be corrected in this way.

Systems, devices, computer-implemented methods, and/or computer program products that facilitate low power, wideband multitone generation. In one example, a multitone generator device can comprise a controller operatively coupled to first and second digital-to-analog converters (DACs). The controller can apply different delays of a sampling signal to the first and second DACs to facilitate sideband suppression of signals output by the first and second DACs. One aspect of such a multitone generator device is that the multitone generator device can facilitate low power, wideband multitone generation.