1689 results about "Frequency measurements" patented technology

An audio fingerprinting system and method. A server receives an audio fingerprint of a first audio piece, searches a database for the audio fingerprint, retrieves an audio profile vector associated with the audio fingerprint, updates user preference information based on the audio profile vector, and selects a second audio piece based on the user preference information. The audio fingerprint is generated by creating a matrix based on the frequency measurements of the audio piece, and performing a singular value decomposition of the matrix. To expedite the search of the database and to increase matching accuracy, a subset of candidates in the database is identified based on the most prominent musical notes of the audio piece, and the search is limited to the identified subset. One of the attributes of the audio profile vector is a particular audio class. An identifier for the audio class is generated based on an average of audio fingerprints of the audio pieces belonging to the audio class.

A method of performing a cell reselection procedure in a wireless communication system includes evaluating priorities of a serving cell and neighbor cells, each of which use different frequency bands, performing inter-frequency measurement on a neighbor cell which has a higher priority than the serving cell, performing the inter-frequency measurement on a neighbor cell which has an equal or lower priority than the serving cell, when a signal characteristic of the serving cell is less than a threshold, and performing cell reselection according to the priorities.

A framework for the cell reselection and associated measurement behavior is proposed based on a state in which a UE is camped on the cell. If the UE is ‘camped in any cell state’, inter-frequency and/or inter-RAT measurements are prioritized over intra-frequency measurements. The proposed scheme helps the UE to find a suitable cell while in the camped on any cell state. If the UE subscribes to specific frequencies, separate measurement rules are implemented to aid the UE to find and camp on the preferred frequencies. The proposed scheme also considers access related information in addition to radio quality to help the UE in making cell selections thereby mitigating the UE from camping on restricted cells. Such aspects minimize situations wherein users are limited due to the service provided by an operator.

A user equipment (UE) is provide which reduces uplink signaling overhead in the process of reporting inter-frequency measurement results over a RACH. For measurement reporting, the UE receives an SIB including a cell information list for non-used frequency cells and a threshold from an RNC, compares signal strengths of signals received from the non-used frequency cells with the threshold, and acquires at least one inter-frequency cell ID indicating at least one non-used frequency cell having signal strength exceeding the threshold from the cell information list. The at least one inter-frequency cell ID is included in a RACH message as measurement result information for the at least one non-used frequency cell, and transmitted to the RNC. The RNC determines that the cell corresponding to the inter-frequency cell ID has signal strength exceeding the threshold.

The invention discloses a power signal frequency detection method and a power signal frequency detection system based on phase modulation. The method comprises the steps: sampling a power signal according to preset signal time span and preset sampling frequency, so as to obtain an input signal sequence; measuring the frequency of the input signal sequence, so as to obtain the initial frequency of the power signal, and subtracting the input signal sequence and the plus or minus 1 Pi phase-shift sequence of the input signal sequence by using the initial frequency as reference frequency, so as to obtain two phase modulation sequences of which phases change along with the input signal frequency; respectively mixing, filtering and integrating the two phase modulation sequences, so as to obtain the phases of the two phase modulation phases for frequency measurement. By implementing the power signal frequency detection method and the power signal frequency detection system, frequency measurement results with higher accuracy can be obtained.

The invention provides a method and system for collecting aggregate information about network traffic, while maintaining processor load relatively constant despite substantial variation in network traffic, and capable of substantially accurate frequency measurement even for relatively infrequent events. A packet monitoring system includes an input port for receiving network packets, a sampling element for selecting a fraction of those packets for review, and a queue of selected packets. The packets in the queue are coupled to a packet-type detector for detecting packets of a selected type; the system applies a measurement technique for determining a frequency measure for those detected packets. The system includes a feedback technique for adaptively altering the sampling rate fraction, responsive to the queue length and possibly other factors, such as processor load or the detected frequency measure. The measurement technique also determines an error range and a measure of confidence that the actual frequency is within the error range of the measured frequency. The system can detect packets of multiple selected types essentially simultaneously, and provide measured frequencies and error ranges for all of the multiple selected types at once. Also, the measurement technique is selected so as to impose relatively light processor load per packet.

The invention relates to a co-existing interference avoiding method and a device, which are used for solving the technical problem that the co-existing interference happens in user equipment (UE) on which multiple wireless technologies coexist. When co-existing interference is detected on the UE, a base station is allowed to know the co-existing interference at the UE side by transmitting a co-existing interference indication or switching a request message, so the UE is switched to a pilot-frequency neighboring region; or the base station ensures that the UE is selectively switched to the pilot-frequency neighboring region according to a reported measurement report by modifying a measuring configuration parameter; or the UE is directly re-connected to the pilot-frequency neighboring region satisfying the access condition through the pilot-frequency measurement. Due to the adoption of the method and the device, the UE is reselected to the pilot-frequency neighboring region so as to avoid the co-existing interference.

The invention relates to a monitoring system for power transmission and transforming equipment, in particular to a capacitive equipment dielectric loss angle online monitoring system. The system is characterized by at least comprising a microprocessor, a leakage current signal acquisition module, a GPS synchronization module, a wireless communication module, an A/D sampling unit, and a frequency measurement sampling unit; in structure, a centralized management mode is used, a wireless data transmission technology and an Internet network technology are applied, and a layered distributed structure is achieved; according to the functional requirements, the invention divides the system into a monitoring layer, a control layer and an information layer. The manufacturer and operating management department (client) can visit the system in different places by only installing browser software and thus easily achieve remote maintenance and monitoring.

The embodiment of the invention discloses a measurement interval configuration method of a pilot frequency measurement non-authorized frequency spectrum and a service base station. The method comprises the following steps: when a measurement signal transmitted on a corresponding channel of the non-authorized frequency spectrum is a short control signal transmission manner, the service base station configures a measurement period of a measurement interval into transmission periods of transmitting the measurement signal by M adjacent cells and one measurement interval is configured in each measurement period according to a pre-set configuration rule, wherein the measurement interval in each measurement period covers a time period for transmitting the measurement signal in one transmission period of the measurement period. By the aid of the measurement interval configuration method, the accuracy of a measurement result of carrying out the pilot frequency measurement on the non-authorized frequency spectrum when the measurement signal is the short control signal transmission manner, and the throughput capacity of terminals in the service cells are can be improved, and the utilization rate of frequency spectrum resources is improved.

The invention provides a frequency measurement method based on an FPGA. A standard reference clock is adopted to count the number of pulses of a measured signal in a unit time (1s) and the number of the pulses of the measured signal in the unit time (1s) is the frequency of the signal. Due to the fact that the starting moment of a gate and the finishing moment of the gate are random for the signal, a pulse period quantization error can be produced, and measurement accuracy needs to be analyzed further: the pulse period of a signal to be measured is set to be Tx, the frequency is set to be Fx, and when the measuring time T equals to 1s, the measurement accuracy & meets the equation that &=Tx/T=1/Fx. The fact that measurement accuracy in a direct frequency measurement method is relevant to the frequency of the signal is known, the higher the frequency of the signal to be measured is, the higher the measurement accuracy is, and otherwise, the lower the frequency of the signal to be measured is, the lower the measurement accuracy is. The direct frequency measurement method is only suitable for measurement of the signal at the higher frequency and can not meet the demand that the measurement accuracy remains unchanged in the whole measurement frequency band. In order to overcome the defect of inaccuracy in low-frequency-band measurement, gating signals and the measured signal are used for carrying out dual control on enable signals of the counter, and therefore accuracy is improved.

For measuring a laser frequency electronic signals can be generated by means of optical interferometers, especially Michelson, Mach-Zehnder and Fabry-Perot interferometers. These signals present profiles with a variation of the laser frequency which are practically identical but shifted in phase by 90°. It is common to generate such phase-shifted signals for frequency measurement in various systems, e.g. by means of a sigmameter, which present, however, disadvantages on account of the great number of the necessary high-quality optical components. The inventive method is based on the analysis of transmission and reflection signals of a Fabry-Perot interferometer (FPI) wherein the signals are obtained from two component beams (PBA and PBB) which are passed through slightly different path lengths within the interferometer. These differences in the length of the optical paths are so selected by different angles of incidence of the component beams into the Fabry-Perot interferometer or by an appropriate shape of the interferometer that the required 90° phase shift is adjusted between the detected intensity signals. From these signals electronic signals can be obtained for detection and also for a rapid correction of the laser frequency.

The present disclosure relates to a communication method and system for converging a 5th-Generation (5G) communication system for supporting higher data rates beyond a 4th-Generation (4G) system with a technology for Internet of Things (IoT). The present disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services. A control method of a user equipment (UE) in a wireless communication system is provided. The method includes receiving packet data conversion protocol (PDCP) configuration information including information indicative of whether a PDCP layer supports out-of-sequence delivery; identifying whether the PDCP layer supports out-of-sequence delivery based on the PDCP configuration information; and processing a PDCP packet data unit (PDU) based on a result of identifying whether the PDCP layer supports out-of-sequence delivery.

Phase-sensitive measurements are made by a resistivity imaging tool in a borehole having non-conductive mud in a conductive earth formation at a plurality of frequencies. From the phase sensitive measurements, the formation resistivity can be determined with higher sensitivity than is possible with the single frequency measurements. Tool standoff can also be determined from a knowledge of the mud resistivity and/or dielectric constant. Formation resistivity may also be determined when the effect of formation capacitance cannot be ignored.

Disclosed is a system and method for stabilizing the carrier-envelope phase of the pulses emitted by a femtosecond mode-locked laser by using the powerful tools of frequency-domain laser stabilization. Control of the pulse-to-pulse carrier-envelope phases was confirmed using temporal cross correlation. This phase stabilization locks the absolute frequencies emitted by the laser, which is used to perform absolute optical frequency measurements that were directly referenced to a stable microwave clock.

The invention discloses a harmonic analysis method based on Kaiser self-convolution window dual-spectrum line interpolation FFT (Fast Fourier Transform) and a device thereof. The method comprises the following steps of sampling a signal: sampling a time-domain continuous signal, and discretizing to obtain an infinitely long discrete sequence; windowing a four-order Kaiser self-convolution window function: performing four-order Kaiser self-convolution window operation on the infinitely long discrete sequence; performing N-point FFT on a windowed and truncated signal to obtain the discrete spectrum of the signal; determining the peak parameter of the discrete spectrum: searching the local spectrum peak of each integer harmonic frequency around the integer harmonic frequency; and calculating a harmonic parameter: solving a coefficient alpha by adopting a discrete spectrum interpolation correction formula based on an LSM (Least Square Method), and calculating parameters such as a harmonic frequency, an amplitude, an initial phase angle and the like. Due to the adoption of the method, the fundamental and harmonic components of a tested signal can be detected rapidly and accurately, and accurate frequency measurement is realized; and the method is convenient for implementing an embedded system, and the tested signal can be detected continuously for a long time.

A method of controlling inertia response of variable-speed wind turbine generator includes following steps. A maximum wind power of the wind turbine is gotten through a wind speed ν_w and a rotation speed ω_r at the hub of the wind turbine based on a maximum wind power tracking control strategy. The maximum wind power is set as an active power control reference value P₀ of the wind turbine. A grid frequency f is obtained via a frequency measurement equipment. An additional active power control reference value ΔP of the wind turbine is generated based on the grid frequency f via an additional control block, and the additional active power control reference value ΔP is added on the active power control reference value P₀, wherein a total of active power control reference value of the wind turbine is P₀+ΔP.

A method for measuring Brillouin backscattering from an optical fibre (18), comprises frequency mixing a first signal with a frequency f B (t) representative of the Brillouin frequency shift in backscattered light received from a deployed optical fibre with a second signal at a frequency f i (t) that varies in time in the same manner as a Brillouin shift previously measured from the fibre to produce a difference signal with a difference frequency iF(t) that has a nominally constant value corresponding to the situation where the received light has a Brillouin shift that matches the previously measured shift. The difference signal is acquired and processed to determine properties of the Brillouin shift and corresponding physical parameters producing the shift. The frequency mixing can be carried out. optically or electrically. Techniques for acquisition of the difference signal include the use of parallel frequency measurement channels and fast rate digital sampling.