An idle tone dispersion device outputs a frequency delta-sigma modulation signal obtained by using either one of a reference signal and a measured signal to perform frequency delta-sigma modulation of the other and dispersing an idle tone. The idle tone dispersion device includes n (n is any natural number equal to or larger than 2) frequency delta-sigma modulation sections and an adder configured to add up output signals of the n frequency delta-sigma modulation sections and output the frequency delta-sigma modulation signal. Each of the n frequency delta-sigma modulation sections uses either one of the reference signal and the measured signal to perform the frequency delta-sigma modulation of the other. At least one of the reference signal and the measured signal includes jitter including a frequency component higher than a frequency of an idle tone of an output signal of the frequency delta-sigma modulation section.

A data collection system pertaining to one embodiment of the present invention collects time-series data which is output from sensors installed on equipment which is a monitored object and carries out detecting an abnormality of the equipment. The data collection system stores plural fault models as data for comparison with time-series data and, in a learning process, determines a range to examine within time-series data by comparing the time-series data with each one of the fault models. An abnormality detection process includes extracting a partial frequency spectrum to examine from the frequency spectrum of time-series data, using information on the range to examine within the time-series data determined through the learning process, and carrying out detecting an abnormality of the equipment using the extracted frequency spectrum.

The apparatus employs magnetoresistive sensors (28) to generate a sinusoid having a time-varying instantaneous frequency commensurate with the instantaneous frequency of the angular displacement of a motor's rotating shaft (40). The resultant signal is then fed to a mixture of fixed-phase-shifting circuits (22) whose outputs are then amplified by voltage-controlled amplifiers and fed to independently wired stator phases (56).

A digital measurement system includes an oscillator, a mixer, and a controller coupled to each other. The oscillator provides a reference signal having a second frequency. The mixer generates a down-converted signal based on the output signal and the reference signal. The controller then determines a characteristic of the output signal (e.g., frequency or phase) based on the down-converted signal. An analog measurement system includes a filter having a center frequency, a rectifier, and a controller. The filter filters the output signal and the rectifier rectifies the filtered signal. The controller samples the rectified signal and determines a characteristic of the output signal based on the level of the rectified signal. The reference signal controller may adjust a characteristic of the output signal based on the determined frequency and/or phase of the output signal.

A digital measurement system includes an oscillator, a mixer, and a controller coupled to each other. The oscillator provides a reference signal having a second frequency. The mixer generates a down-converted signal based on the output signal and the reference signal. The controller then determines a characteristic of the output signal (e.g., frequency or phase) based on the down-converted signal. An analog measurement system includes a filter having a center frequency, a rectifier, and a controller. The filter filters the output signal and the rectifier rectifies the filtered signal. The controller samples the rectified signal and determines a characteristic of the output signal based on the level of the rectified signal. The reference signal controller may adjust a characteristic of the output signal based on the determined frequency and/or phase of the output signal.

A detection device includes: a frequency property acquisition unit that acquires a frequency property when an alternating-current signal is input to at least two conductive bodies provided on a fiber sheet; and a detection signal output unit that outputs a detection signal when the frequency property acquisition unit acquires a predetermined frequency property.

A passive intermodulation (PIM) measurement device for measuring a PIM in at least one of installation equipments and a distribution network within a distributed antenna system (DAS), the PIM measurement device included in a relay unit of the DAS the PIM measurement device includes a pulse generation unit a PIM detection unit and a controller. The pulse generation unit generates a two-tone pulse signal having frequencies different from each other. The PIM detection unit detects intermodulation (IM) signals fed back from the installation equipments or the distribution network in the DAS corresponding to the propagation of the two-tone pulse signal. The controller detects PIM generation information in the DAS based on the fed-back IM signal.

An apparatus and method for monitoring the performance of a power line filter. The apparatus for monitoring the performance of a power line filter includes a performance degradation monitoring unit for monitoring performance degradation of individual components constituting a power line filter, and then generating performance degradation information, a frequency characteristic measurement unit for measuring frequency characteristics of the power line filter, and a performance monitoring unit for determining at least one of an operating state and performance of the power line filter based on the performance degradation information of the individual components and information on the frequency characteristics of the power line filter.

An apparatus and method for monitoring the performance of a power line filter. The apparatus for monitoring the performance of a power line filter includes a performance degradation monitoring unit for monitoring performance degradation of individual components constituting a power line filter, and then generating performance degradation information, a frequency characteristic measurement unit for measuring frequency characteristics of the power line filter, and a performance monitoring unit for determining at least one of an operating state and performance of the power line filter based on the performance degradation information of the individual components and information on the frequency characteristics of the power line filter.

A tool is presented herein capable of performing several electrical measurements and generating several electrical outputs. The tool can be configured to perform measurements and provide outputs most commonly utilized when developing and diagnosing failures of a hardware platform based around a microcontroller. The tool can have a form factor and a header configuration compatible for mating with an external microcontroller or minicomputer developer board such as Arduino, UDOO, Raspberry Pi, TI LaunchPad, STM Nucleo, BeagleBone, etc.