A system for non-invasive sensing of radio-frequency current spectra. In one example, the system comprises a plasma processing chamber, a plasma generator, and a shunt connector having a resistor therein. In one example, the shunt connector is attached across an opening in a ground-return path between the chamber and the generator.

System and method for machine condition monitoring using phase adjusted vector averaging. An analog signal from a sensor measuring a machine parameter may be acquired, thereby generating a first digital signal that includes multiple analysis blocks of data. For each analysis block, a complex valued frequency spectrum (CVFS) may be computed via a Discrete Fourier transform (DFT), at least one reference frequency may be specified, and a complex valued phase compensation vector that preserves magnitude while adjusting phase constructed to achieve coherence between reference frequency components (RFCs) and the selected analysis block. The CVFS may be phase compensated by multiplying the complex valued phase compensation vector with the complex-valued frequency spectrum. The complex valued frequency spectra of the analysis blocks may be vector averaged, thereby improving signal to noise ratio at specified frequencies. RFCs in the averaged spectrum may be identified, thereby generating average RFCs analyzable to determine machine condition.

A measuring device for measuring a signal of interest within a measuring signal is provided. It device comprises a trace determiner, which is adapted to consecutively determine a first stack of traces of the measuring signal, a statistics evaluator, adapted to, after each trace of said first stack of traces is determined by the trace determiner, statistically evaluate if a presence of the signal of interest is detected with a first pre-set degree of certainty, wherein the trace determiner is adapted to cease determining said traces of said first stack of traces, when the statistics evaluator has determined that the signal of interest has been detected to the first pre-set degree of certainty. Preferably a parameter determiner is, adapted to determine measuring parameters, based upon the statistical evaluation.

A frequency measurement method and a system thereof are provided. The method includes: generating to-be-detected emergent light under an action of the electro-optical crystal when a light source irradiates an electro-optical crystal disposed in the microwave electric field; detecting, by a single-photon detector, the to-be-detected emergent light to obtain a detection result of the single-photon detector; and determining a frequency of the microwave signal based on the detection result of the single-photon detector and a Fourier transform algorithm.

A frequency measurement method and a system thereof are provided. The method includes: generating to-be-detected emergent light under an action of the electro-optical crystal when a light source irradiates an electro-optical crystal disposed in the microwave electric field; detecting, by a single-photon detector, the to-be-detected emergent light to obtain a detection result of the single-photon detector; and determining a frequency of the microwave signal based on the detection result of the single-photon detector and a Fourier transform algorithm.

A power conversion device of an embodiment includes a rectifier that full-wave rectifies alternating current of a plurality of phases supplied from a power supply side, a capacitor that smoothes an output voltage of the rectifier, a voltage detection unit that detects the smoothed voltage, and an open phase detection unit that detects that an open phase has occurred in the alternating current of the plurality of phases based on a component having a frequency that is twice as high as a fundamental frequency of the alternating current of the plurality of phases included in frequency components of the smoothed voltage.

A power conversion device of an embodiment includes a rectifier that full-wave rectifies alternating current of a plurality of phases supplied from a power supply side, a capacitor that smoothes an output voltage of the rectifier, a voltage detection unit that detects the smoothed voltage, and an open phase detection unit that detects that an open phase has occurred in the alternating current of the plurality of phases based on a component having a frequency that is twice as high as a fundamental frequency of the alternating current of the plurality of phases included in frequency components of the smoothed voltage.

The disclosed technology relates to a method and apparatus for graphically displaying a switching cycle of a switching device. A switching voltage and a switching current are acquired for a device under test via a voltage probe and a current probe, respectively, for a plurality of switching cycles of the device under test. The switching current versus the switching voltage is plotted on a current versus voltage plot as a curve for each of the switching cycles. Each of the curves on the current versus voltage plot overlap each other and are displayed to a user.

An oscilloscope including an input port for receiving training data including waveforms and corresponding known classifications and a processor for training a plurality of classifiers on the training data. Training includes iteratively applying each classifier to each waveform of the training data to obtain corresponding predicted waveform classifications and comparing the predicted waveform classifications with the known classifications. Classifiers are corrected when predicted waveform classifications does not match the known classifications. Models for each classification are constructed with suggested measurements or actions. Subsequently, live waveform data is captured by the oscilloscope and the classifiers are applied to the live data. When a confidence value for a single classification exceeds a threshold, the waveform data is classified, and suggested measurements or actions are implemented in the oscilloscope based on the classification.

An oscilloscope including an input port for receiving training data including waveforms and corresponding known classifications and a processor for training a plurality of classifiers on the training data. Training includes iteratively applying each classifier to each waveform of the training data to obtain corresponding predicted waveform classifications and comparing the predicted waveform classifications with the known classifications. Classifiers are corrected when predicted waveform classifications does not match the known classifications. Models for each classification are constructed with suggested measurements or actions. Subsequently, live waveform data is captured by the oscilloscope and the classifiers are applied to the live data. When a confidence value for a single classification exceeds a threshold, the waveform data is classified, and suggested measurements or actions are implemented in the oscilloscope based on the classification.