A measuring system for performing over the air power measurements is provided. The measuring system comprises, within a single housing, a detector module, comprising a detector input, a transmitter module, comprising a transmitter output, and an antenna. The detector input and the transmitter output are at least temporarily connected. At least the transmitter output or the detector input are at least temporarily connected to the antenna.

Analysis of smart meter and/or similar data based on frequency content is disclosed. In various embodiments, for each of a plurality of resource consumption nodes a time series data including for each of a series of observation times a corresponding resource consumption data associated with that observation time is received. At least a portion of the time series data, for each of at least a subset of the plurality of resource consumption nodes, is transformed into a frequency domain. A feature set based at least in part on the resource consumption data as transformed into the frequency domain is used to detect that resource consumption data associated with a particular resource consumption node is anomalous.

Analysis of smart meter and/or similar data based on frequency content is disclosed. In various embodiments, for each of a plurality of resource consumption nodes a time series data including for each of a series of observation times a corresponding resource consumption data associated with that observation time is received. At least a portion of the time series data, for each of at least a subset of the plurality of resource consumption nodes, is transformed into a frequency domain. A feature set based at least in part on the resource consumption data as transformed into the frequency domain is used to detect that resource consumption data associated with a particular resource consumption node is anomalous.

There are provided a method, a system and a device for calibrating a frequency of a driving voltage waveform for a linear resonance device. An actual sampling frequency is continuously corrected, so that a difference between a measured natural frequency of the linear resonance device obtained during a calibration process and a frequency of a standard driving voltage waveform stored in a driving chip for the linear resonance device is in a predetermined range. The driving chip outputs a driving waveform at a finally corrected actual sampling frequency, to drive the linear resonance device. Further, only an actual sampling frequency is required to be adjusted, and it is not required to modify waveform data stored in the driving chip for the linear resonance device.

In certain embodiments, an apparatus includes a sensing element having a capacitance to a first reference voltage. The capacitance is variable as a function of a proximity of an object to the sensing element. The apparatus further includes a sample capacitor connected to the sensing element and control circuitry connected to the sample capacitor. The control circuitry is configured to supply a charge to the sample capacitor and the sensing element and discharge the sensing element. The control circuitry is further configured to provide, in response to the discharge of the sensing element, a signal indicative of the capacitance to the first reference voltage of the sensing element. The control circuitry is further configured to process the signal to detect a change in the capacitance to the first reference voltage as indicative of the proximity of the object to the sensing element.

A method for determining characteristic parameters of an electrostatic actuation oscillator, where the method includes generating a first excitation voltage defined as being the sum of a first sinusoidal voltage and a voltage pulse; applying the first excitation voltage at the input of the oscillator; acquiring in the time domain a first response voltage present at the output of the oscillator when the first excitation voltage is applied at the input of the oscillator; obtaining, by transformation in the frequency domain, a first amplitude spectral density of the first response voltage; determining the characteristic parameters of the oscillator from the first amplitude spectral density.

A method for determining characteristic parameters of an electrostatic actuation oscillator, where the method includes generating a first excitation voltage defined as being the sum of a first sinusoidal voltage and a voltage pulse; applying the first excitation voltage at the input of the oscillator; acquiring in the time domain a first response voltage present at the output of the oscillator when the first excitation voltage is applied at the input of the oscillator; obtaining, by transformation in the frequency domain, a first amplitude spectral density of the first response voltage; determining the characteristic parameters of the oscillator from the first amplitude spectral density.

A constant current source, a stable time base and a capacitor are used to self-check operation of an analog-to-digital convertor (ADC) by charging the capacitor for a pre-determined amount of time to produce a voltage thereon. This voltage will be proportional to the amount of time that the capacitor was charged. Multiple points on the ADC transfer function can be verified in this self-check procedure simply by varying the amount of time for charging of the capacitor. Relative accuracy among test points may then be easily obtained. Absolute accuracy may be obtained by using an accurate clock reference for the time base, a known current source and capacitor value.

Apparatus (1) for use in disturbance evaluation systems based on disturbance extraction, which apparatus (1) comprises measuring means for obtaining signal frequency both before (4) and after a disturbance (3) in an electricity network but excluding use of the disturbance transient itself, and interpolation means (5) for interpolating frequency across the disturbance interval to reflect the underlying frequency trend (9) uninfluenced by the disturbance transient. The apparatus (1) may include: (i) at least one delay means (2) for receiving at least one analogue or digital signal (6) from the electricity network; (ii) at least one first access point (P) at a first part of the delay means (2); (iii) at least one second access point (Q) at a second part of the delay means (2), and the apparatus (1) being such that: (iv) the measuring means comprises: (a) a first frequency derivation means (3) for processing a set of access point outputs from the first access point and providing at least one measure of frequency (7) after the disturbance; and (b) a second frequency derivation means (4) for processing a set of access point outputs from the second access point or a delayed output means, for providing at least one measure of frequency (8) before the disturbance; and the interpolation means (5) receives the measure of frequency (7) after the disturbance and the measure of frequency (8) before the disturbance, and provides a measure of frequency (9) as a function of time over a period of interest, which comprises the disturbance interval and either side of the disturbance interval.

Apparatus (1) for use in disturbance evaluation systems based on disturbance extraction, which apparatus (1) comprises measuring means for obtaining signal frequency both before (4) and after a disturbance (3) in an electricity network but excluding use of the disturbance transient itself, and interpolation means (5) for interpolating frequency across the disturbance interval to reflect the underlying frequency trend (9) uninfluenced by the disturbance transient. The apparatus (1) may include: (i) at least one delay means (2) for receiving at least one analogue or digital signal (6) from the electricity network; (ii) at least one first access point (P) at a first part of the delay means (2); (iii) at least one second access point (Q) at a second part of the delay means (2), and the apparatus (1) being such that: (iv) the measuring means comprises: (a) a first frequency derivation means (3) for processing a set of access point outputs from the first access point and providing at least one measure of frequency (7) after the disturbance; and (b) a second frequency derivation means (4) for processing a set of access point outputs from the second access point or a delayed output means, for providing at least one measure of frequency (8) before the disturbance; and the interpolation means (5) receives the measure of frequency (7) after the disturbance and the measure of frequency (8) before the disturbance, and provides a measure of frequency (9) as a function of time over a period of interest, which comprises the disturbance interval and either side of the disturbance interval.