1869results about "Noise figure or signal-to-noise ratio measurement" patented technology

A system is disclosed for detecting and calculating the level of ambient and / or environmental noise, such as electromagnetic interference generated by electric power lines, ambient lights, light dimmers, television or computer displays, power supplies or transformers, and medical equipment. In some embodiments, the system performs frequency analysis on the interference signal detected by light photodetectors and determines the power of the interference signal concentrated in the analyzed frequency bands. The worst-case interference level can be determined by selecting the maximum from the computed power values. In some embodiments, the determined interference signal power can be compared with the noise tolerance of a patient monitoring system configured to reliably and non-invasively detect physiological parameters of a user. The results of the comparison can be presented to the user audio-visually. In some embodiments, the system can be used to perform spot check measurements of electromagnetic interference.

An integrated circuit identification device (ICID) to be incorporated into an integrated circuit (IC) includes an array of electronic cells in which the magnitude of an output signal of each cell is a function of randomly occurring parametric variations which vary from cell-to-cell. The ICID also includes a circuit for measuring the output of each cell and for producing output data having a value reflecting the particular combination of measured characteristics of all of the elements of the array. When we make the number of elements in the array large enough, we insure that to a high degree of probability, the pattern of measured array cell characteristics for an ICID embedded in any one IC will be unique and distinguishable from such patterns measured by ICIDs embedded in millions of other ICs. Thus the value of the output data produced by an ICID circuit acts as a unique "fingerprint" for the IC in which it is installed, and can be used as a unique identification (ID) for that IC.

A system is disposed at a location of a utility commodity subscriber for informing the subscriber of utility commodity cost and usage and for controlling utility commodity usage. The system includes one or more utility meters, an information and control apparatus, a first data communication link, and a second data communication link. The one or more meters measure usage of one or more utility commodity and for generating one or more usage signals including a measurement of the subscriber's usage of the one or more utility commodities. The information and control apparatus includes a microprocessor, a memory, a clock, and a user interface, for inputting and outputting information. The first data communication link is between the one or more utility meters and the information and control apparatus and provides the one or more usage signals to said information and control apparatus for storage in the memory. The second data communication link is between the information and control apparatus and one or more central locations associated with the one or more utility commodity. The second communication link also provides rate information related to usage of the one or more utility commodity from the one or more central location to the information and control apparatus and provides utility commodity usage data from the information and control apparatus to the one or more central location. The microprocessor computes an accumulated cost of one or more utility commodity for a predetermined period of time according to the clock, the one or more usage signal, and the rate information. Information related to the accumulated cost is provided to the user interface for output to the subscriber.

A communication device, for connecting one or more electrical appliances to a remote service centre, comprises a control unit (AMC), means (PLG) for connecting the device (HG) to an alternating voltage electric mains network (Vac) and means (SK) for supplying the alternating mains voltage (Vac) to a power supply line of an electric appliance. The device (HG) further comprises first communication means (CSA), prearranged for receiving information possibly generated by the electric appliance and transmitted through the power supply line thereof, second communication means (ZB), prearranged for establishing a connection with a local area network (HN1) and third communication means (GGM), prearranged for establishing a connection with a further communication network, different from the local network (HN1), to which the remote service centre is connected. The control unit (AMC) is prearranged for acquiring by means of the first communication means (CSA), first information possibly generated by the electric appliance and transmitted through the power supply line thereof and / or second information regarding electric energy consumptions associated to the operation of is the electric appliance, acquiring, by means of the second communication means (ZB), third information possibly available on the local network (HN1), and transmitting to the remote centre (RMC), by means of the third communication means (GGM), at least one of the first, second and third information.

The method of reducing contamination of electrical signals recorded in the presence of repeated interference contamination comprises obtaining an electrical signal recorded in the presence of a contaminating signal, and detecting a timing signal that occurs at a fixed time point during the electrical signal relative to the onset of the contaminating signal. The electrical signal is digitized, wherein the digitizing begins with the timing signal. A plurality of digitized electrical signals is analyzed, wherein the electrical signals are synchronized with respect to the timing signal, to obtain an estimated contaminating signal that is subtracted from the digitized electrical signal. This method can be used with electrophysiological signals, such as EEG, ECG, EMG and galvanic skin response, and for elimination of noise associated with concurrently used methods such as MRI. The method of noise reduction is applicable to recordings of other electrical signals, including audio recordings.

In a speech communications network, continuous play of audio packets is achieved using a jitter buffer in a receiver. Audio packets are stored in the jitter buffer before decoding the audio packets into an audible output. When the level of stored audio packets approaches the full capacity of the jitter buffer, the rate at which the audio packets are played out of the jitter buffer is increased signaling a compression operation in the decoder. When the level of stored audio packets approaches an empty level of the jitter buffer, the rate which the audio packets are played out of the jitter buffer is reduced signaling an expansion operation in the decoder. Audio packets are not modified when the level of stored audio packets is within a predetermined range. A speed controller is provided to instruct the decoder to decode the audio packets according to either a compressed, expanded or normal audio packet status.

An arc fault detector system detects arcing faults in an electrical distribution system by monitoring one or more conductors and producing an input signal representing one or more electrical signal conditions in the circuit to be monitored. This input signal is processed to develop signals representing the electrical current flow through the monitored circuit and broadband noise signal components. The system analyzes these signals to determine whether an arcing fault is present, and if so, outputs a trip signal which may be used directly or indirectly to trip a circuit breaker or other circuit interruption device.

A method and apparatus for anti-islanding of distributed power generation systems having an inverter comprising a phase locked loop (PLL), a phase shift generator for injecting a phase shift into the PLL during at least one sample period, and a phase error signature monitor for monitoring at least one phase error response of the PLL during the at least one sample period.

Systems and methods for the design or implementation of statistical filters for use in the spectral shaping of transmissions are disclosed. A desired power spectrum may be mapped to find pole locations that approximate the desired spectrum. These pole locations may then be mapped to the edge or inside of an equilateral polygon lying inside a unit circle, the equilateral polygon having the same number of sides as the order of the statistical filter desired and one vertex mapped to unity, to yield a set of eigenvalues. These eigenvalues may be the eigenvalues of a stochastic matrix the elements of which may be the Markov transition probabilities for use in a statistical filter designed to achieve the desired power spectrum. Use of a statistical filter employing these Markov transition values may be utilized to shape UWB or other signals to achieve the desired power spectrum.

The start up performance of an ultrasonic system under zero load conditions is improved by setting a phase set point in a frequency control loop such that, at start up under zero load conditions, the phase set point intersects a point on a phase-frequency response curve which has a low positive slope. This intersection point on the phase-frequency response curve changes as the load is increased and the system Q is decreased. The controller “seeks” a target 0° impedance phase angle. The frequency of the ultrasonic generator is set to an off-resonance frequency which is lower than the resonance of any known hand piece / blade combination. In order for the drive voltage to not exceed the physical limit of the system, the drive current is set to a low level. The drive frequency is then smoothly increased in steps until the target 0° impedance phase delta is located.

Methods and systems incorporating non-linear dynamic (NLD) analysis such as entropy or other complexity analysis monitoring continuous or evoked signals from a biological subject are presented, where such a system comprises of processing steps including: a) the combination of a biological signal evoked as a result of patient stimulation presented to a biological subject and a non-linear analysis method capable of capturing temporal changes in signal order or regularity; b) any combination of processed evoked or continuous central nervous or peripheral physiological mechanisms b) a means to generate a measure indicative of a patient's level of anaesthesia and consciousness depth (A&CD), sedation or sleep / wake state. Methods and systems incorporating a NLD analysis means to improve the discrimination between different signals origins including any combination of: a) central nervous system (CNS), b) peripheral control or nervous system (PNS), c) autonomic control or nervous system (ANS), d) arousals, and e) artifacts.

A method of displaying signals containing a spatial and a temporal aspect, where multiple signals are received by multiple sensors. The received signals are decomposed into separate signal components within one or more distinct frequency bands. Signal components are isolated within each frequency band based on differences between the signal components within the same frequency band, and the signal components are displayed. The signal components may be analyzed to determine a time course of activity and a location of the associated source. Representations of the source may also be generated and displayed to aid in monitoring the signals.

A method for determining position and alignment is provided. The method includes monitoring a first and second sequence of ultrasonic signals transmitted from the first device to a second device, estimating a location of the first device from Time of Flight measurements of the ultrasonic signals at respective microphones on the second device, calculating a set of phase differences, weighting a difference of an expected location and estimated location of the first device with the set of phase differences to produce a relative displacement, and reporting a position of the first device based on the relative displacement.

A method and circuit for measuring a statistical value of jitter for a data signal having a data rate fD, comprises digitally sampling the data signal at a sampling rate, fS, to produce sampled logic values, where fD / fS is a predetermined non-integer ratio; and analyzing the sampled values to deduce a statistical value of the jitter.

Methods and apparatuses to calibrate read / write memory accesses through data buses of different lengths via advanced memory buffers. One embodiment includes an advanced memory buffer (AMB) having: a plurality of ports to interface respectively with a plurality of data buses; a port to interface with a common clock bus for the plurality of data buses; and an adjustable circuit coupled with the plurality of ports to level delays on the plurality of data buses. In one embodiment, the data buses have different wire lengths between the dynamic random access memory (DRAM) memory chips and the advanced memory buffer (AMB).

An apparatus determines a characteristic of a portion of a power line. The apparatus comprises a coupling device in communication with a processor. The coupling device receives a signal from a power line and the processor receives the signal from the coupling device and determines a characteristic of a portion of the power line based on the received signal.

A method of establishing a benchmark for a figure of merit indicative of flicker noise of an amplifier circuit.

Weather forecasting systems and methods for deriving and producing very short-term weather forecasts. Weather data and forecast information maybe input to derive very short-term weather forecasts in the 0-6 hour time frame. The system and methods include an expert system employing a hybrid or blending of forecasting approaches, with dynamic or intelligent arbitration of the different numerical, statistical, and human-driven techniques to produce more accurate weather forecasts for very short-term time periods. A calibration or internal verification against ground truth may be run independently with a time lag to produce more accurate future predictions of atmospheric state. The systems and methods may run in modes that produce either high resolution weather forecasts in the short-term period of 0-6 hours or a combination of synthetic, real-time weather observations / conditions and high resolution, short-term weather forecasts.

In a capacitive sensor of the type having X electrodes which are driven and Y electrodes that are used as sense channels connected to charge measurement capacitors, signal measurements are made conventionally by driving the X electrodes to transfer successive packets of charge to the charge measurement capacitors. However, an additional noise measurement is made by emulating or mimicking the signal measurement, but without driving the X electrodes. The packets of charge transferred to the charge accumulation capacitor are then indicative of noise induced on the XY sensing nodes. These noise measurements can be used to configure post-processing of the signal measurements.

Disclosed is a UHF partial discharge and its location measuring device for high-voltage power devices. The measuring device includes a partial discharge sensor, an external noise sensor, an analogue-digital converter, a peak detector, a partial discharge signal processor, an arrival time detector, a discharge location processor, and a display unit.

When a disturbance (for example, lightning strike) occurs on a high-voltage overhead transmission line, the line must be checked for any possible damage. If the distance-to-fault is known, line crews can be quickly dispatched for any necessary repair. The present invention is a fault location method and system that uses filtered, time-synchronized positive- or negative-sequence voltage and current measurements from both ends of the overhead transmission line to determine the exact distance to the fault with respect to either end.

Apparatus for determining the frequency of an ac power signal, includes sensing circuitry to sense the ac signal. In a digital implementation of the invention, a double average of the samples is generated by a processor as the sum of the most recent sample, twice the next most recent sample plus the third most recent sample. The least mean square of a running window of the most recent double average signals is generated to avoid discontinuities at the zero crossings and to reduce the effects of noise. The frequency is determined from this least mean square value of the window of double average signals. As implemented in a protective relay, a trip signal is generated if the frequency is out of limits.

A data alignment algorithm that automatically aligns data from multiple monitoring devices to the same zero-crossings at the same point in time. Cycle-by-cycle frequency data is received from each monitoring device and a cross-correlation algorithm is performed to determine a correlation coefficient between a reference monitoring device and another monitoring device. The data of the other monitoring device is shifted by one cycle and another correlation coefficient is calculated by the cross-correlation algorithm. The data of the two monitoring devices is aligned at the point at which the maximum correlation coefficient is calculated or the point at which the correlation coefficient exceeds a threshold value. The clocks of the monitoring devices can also be synchronized at the same point of alignment.

An improved micro-inverter apparatus is disclosed for intelligently controlling energy harvest from photovoltaic solar panels based on one or more adjustable, user-defined variables. The improved micro-inverter apparatus may include a microcontroller configured to monitor the operating temperature of its micro-inverter and control the power harvested from associated solar panels in order to ensure the operating temperature of the micro-inverter does not approach a level that would damage the micro-inverter's circuitry or other components. Similarly, the micro-inverter apparatuses' microcontroller may be configured to monitor the total harmonic distortion of the micro-inverter's AC power output and control the power harvested from associated solar panels in order to ensure the total harmonic distortion of the AC power output does not exceed a threshold level.