A system and method for analog estimation of a spectral correlation function (SCF) provides a photonic carrier to generate a signal comb and offset comb, each comprising N comb tones separated by respective repetition rates ΔF and ΔF+δF. The signal and offset combs are amplitude-modulated according to an inbound RF signal of interest and filtered via periodic optical filters to produce a sequence of N Fourier components of the signal comb and N Fourier components of the offset comb, each filtered signal comb component overlapping with a filtered offset comb component. In-phase/quadrature (I/Q) components of the products of each component of the complex conjugate of the filtered offset comb and the overlapping counterpart of the filtered signal comb are generated in an optical receiver and digitized into slices of the SCF at a fixed time instance and center frequency, correlated at various cyclic separations α.

Spatially resolved Fourier Transform Impedance Spectroscopy (FTIS) is disclosed to spatially map and quickly build the frequency response of optoelectronic devices using optical probes. The transfer function of a linear system is the Fourier transform of its impulse response, which may be obtained from transient photocurrent measurements of devices such as photodetectors and solar cells. We apply FTIS to a PbS colloidal quantum dot (QD)/SiC heterojunction photodiode and corroborate results using intensity-modulated photocurrent spectroscopy. The cutoff frequencies of the QD/SiC devices were as high as ˜10 kHz, demonstrating their utility in advanced flexible and thin film electronics. The practical frequencies for FTIS lie in the mHz-kHz range, ideal for composite or novel materials such as QD films that are dominated by interfacial trap states.

Provided are a method and device for identifying an individual appliance through analysis of a harmonic component of a power signal. An operating appliance identification method includes collecting a mixed load signal from a home power distribution network, generating a first candidate appliance list by selecting first candidate appliances among individual appliances registered in an individual appliance harmonic analysis information table based on a ratio of a harmonic component value included in the mixed load signal, generating a second candidate appliance list including second candidate appliances by filtering the first candidate appliances based on a magnitude of the harmonic component value included in the mixed load signal, and identifying an operating appliance among a plurality of appliances connected to the home power distribution network by using the second candidate appliance list.

Collect a full band capture spectral reading from a plurality of cable/fiber broadband network customer units (e.g., cable modems or equivalent optical units); for each of the cable/fiber broadband network customer units, construct an ideal spectral reading. For each of the cable/fiber broadband network customer units, subtract the ideal spectral reading from the full band capture spectral reading to obtain a resultant spectrum. For at least one of the cable/fiber broadband network customer units, identify a persistent deviation from zero in the resultant spectrum that does not match a known impairment type. Identify at least one new impairment type corresponding to the persistent deviation from zero. Remediation of the new impairment type can be carried out as appropriate, and/or a detection pattern can be deployed to identify future occurrences of the new impairment type.

Collect a full band capture spectral reading from a plurality of cable/fiber broadband network customer units (e.g., cable modems or equivalent optical units); for each of the cable/fiber broadband network customer units, construct an ideal spectral reading. For each of the cable/fiber broadband network customer units, subtract the ideal spectral reading from the full band capture spectral reading to obtain a resultant spectrum. For at least one of the cable/fiber broadband network customer units, identify a persistent deviation from zero in the resultant spectrum that does not match a known impairment type. Identify at least one new impairment type corresponding to the persistent deviation from zero. Remediation of the new impairment type can be carried out as appropriate, and/or a detection pattern can be deployed to identify future occurrences of the new impairment type.

The disclosure relates to a method for determination of an operating state of a compressor and/or a rotational speed of a compressor drive of the compressor comprising; measuring, over a time range, a magnetic field associated with one or more phases of an electrical power supply conductor supplying the compressor with electrical power; wherein the magnetic field is measured by a detection element to provide a representation of the magnetic field; determining a frequency spectrum of the representation of the magnetic field over the time range; and analyzing the frequency spectrum of the representation of the magnetic field over the time range to determine an operating state of the compressor and/or to determine a rotational speed of the compressor drive. The disclosure further relates to a device for carrying out the method, a compressor measuring system, and a computer-readable storage medium.

The disclosure relates to a method for determination of an operating state of a compressor and/or a rotational speed of a compressor drive of the compressor comprising; measuring, over a time range, a magnetic field associated with one or more phases of an electrical power supply conductor supplying the compressor with electrical power; wherein the magnetic field is measured by a detection element to provide a representation of the magnetic field; determining a frequency spectrum of the representation of the magnetic field over the time range; and analyzing the frequency spectrum of the representation of the magnetic field over the time range to determine an operating state of the compressor and/or to determine a rotational speed of the compressor drive. The disclosure further relates to a device for carrying out the method, a compressor measuring system, and a computer-readable storage medium.

According to one embodiment, an anomaly detection apparatus includes a processing circuit configured to calculate a reconstruction error of an input signal being a time-series signal, calculate cycle information indicating cyclic property of the reconstruction error, and determine presence/absence of an anomaly signal in the input signal on the basis of the cycle information or the cycle information and the reconstruction error.

According to one embodiment, an anomaly detection apparatus includes a processing circuit configured to calculate a reconstruction error of an input signal being a time-series signal, calculate cycle information indicating cyclic property of the reconstruction error, and determine presence/absence of an anomaly signal in the input signal on the basis of the cycle information or the cycle information and the reconstruction error.

A method of analysing a spectrum on which information is transmitted, comprising: determining each different type of modulation used for transmitting the information across the spectrum, for each determined modulation, identifying its carrier frequency and its bandwidth, defining characteristics of usage of the spectrum in terms of the determined modulations and their corresponding carrier frequencies and bandwidths.