Abstract:
A device for measuring the phase-noise spectrum of a pulsed sinusoidal signal generates a pulsed sinusoidal signal, converts the analog pulsed sinusoidal signal into a corresponding digital, pulsed sinusoidal signal and mixes the digital, pulsed sinusoidal signal into the baseband by means of quadrature mixing. Following this, the phase of the pulsed sinusoidal signal in the baseband is determined by means of Fourier transform of the phase of the pulsed sinusoidal signal, the phase spectrum of the pulsed sinusoidal signal is determined, and the phase-noise spectrum of the pulsed sinusoidal signal is determined by removing the spectral lines associated with the sinusoidal signal from the phase spectrum. According to the invention, the pulse pauses are removed from the pulsed sinusoidal signal in the baseband.
Abstract:
A long range wireless phasing voltmeter determines the phase difference between the time-varying voltage carried on a reference electrical conductor and another, field conductor. The voltage signal from the reference conductor is measured by a reference probe and compared by a first unit in communication with that reference probe to a precision 60 Hz signal generated from a GPS receiver. The phase difference between these, in the form of a nine-bit, audible signal using frequency shift keying to modulate the carrier frequency, is transmitted by the first unit to a second unit perhaps miles away. A receiver in the second unit decodes the signal and uses another precision 60 Hz signal generated from another GPS receiver to re-create a surrogate of the original reference voltage signal. This surrogate signal is forwarded to a meter probe that is measuring the signal on a field conductor. The meter probe can then compare the two signals to determine the phase angle difference between them.
Abstract:
A long range wireless electrical phasing system using a centrally located beacon to transmit reference phase angle information to any number of locally handheld (Meter Probes) display modules containing a receiver to receive the distant beacon signal and a contact electrode used to contact a local electrical conductor. The display module processes the distant message and local electrical phase information and displays the exact phase angle difference of the local electrical conductor with respect to a distant reference phase.
Abstract:
A Stein Hall cup for measuring the viscosity of a starch adhesive is automated to provide viscosity measurement in real time using a PLC or other data gathering and control processor. Temperature of the adhesive is measured concurrently with viscosity and temperature signals are processed with the timed viscosity signal to provide a temperature compensated value of starch viscosity.
Abstract:
Voltage instantaneous value time-series estimation data and a present-time voltage estimation value are calculated by using an actually-measured frequency and voltage instantaneous value time-series data according to a least square method. A present-time voltage effective value is determined by using the calculated voltage instantaneous value time-series estimation data, and a present-time synchrophasor, a voltage distortion degree and an inter-bus-line synchrophasor phase angle difference are determined by using the present-time voltage effective value and the present-time voltage estimation value.
Abstract:
The present invention relates to a method and apparatus for measuring a frequency or a phase of a measuring signal, wherein the frequency (fg) or the phase (φg) are estimated by approximating the relationship between a collecting clock (c) and a gating clock (g) based on a non-linear step-shaped function. Thereby, the estimation error can be improved with almost negligible complexity increase in signal processing.
Abstract:
Accelerometers have a number of wide-ranging uses, and it is desirable to both increase their accuracy while decreasing size. Here, millimeter or sub-millimeter wavelength accelerometers are provided which has the advantage of having the high accuracy of an optical accelerometer, while being compact. Additionally, because millimeter or sub-millimeter wavelength signals are employed, cumbersome and awkward on-chip optical devices and bulky optical mediums can be avoided.
Abstract:
A frequency change detector splits a frequency standard signal into two undelayed frequency signals, one of which is delayed by a predetermined amount. The delayed signal is then mixed with the undelayed frequency signal into a mixed signal that is further filtered and amplified for providing an output signal indicating frequency changes of the frequency standard signal. The mixed frequency signal indicates frequency changes of the original frequency standard signal without reference to another frequency standard. This frequency change detector is well suited for use on satellites as an early warning detection of changes in on-board atomic frequency standards.
Abstract:
Voltage instantaneous value time-series estimation data and a present-time voltage estimation value are calculated by using an actually-measured frequency and voltage instantaneous value time-series data according to a least square method. A present-time voltage effective value is determined by using the calculated voltage instantaneous value time-series estimation data, and a present-time synchrophasor, a voltage distortion degree and an inter-bus-line synchrophasor phase angle difference are determined by using the present-time voltage effective value and the present-time voltage estimation value.
Abstract:
A phasemeter for estimating the phase of a signal. For multi-tone signals, multiple phase estimates may be provided. An embodiment includes components operating in the digital domain, where a sampled input signal is multiplied by cosine and sine terms to provide estimates of the inphase and quadrature components. The quadrature component provides an error signal that is provided to a feedback loop, the feedback loop providing a model phase that tends to track the phase of a tone in the input signal. The cosine and sine terms are generated from the model phase. The inphase and quadrature components are used to form a residual phase, which is added to the model phase to provide an estimate of the phase of the input signal. Other embodiments are described and claimed.