26results about "Frequency to pulse train conversion" patented technology

The embodiment of the invention provides a signal period measurement method, a microcontroller, a storage medium and a program product, and relates to the technical field of signal frequency detection, the method comprises the following steps: in response to a timer capture event or a timer overflow event, executing an interrupt service program of a central processing unit; executing the interrupt service program of the central processing unit, which comprises the following steps of: when the interrupt service program is determined to be called in response to the timer overflow event, performing cumulative counting on the occurrence frequency of the timer overflow event to obtain a cumulative overflow frequency; and under the condition of determining that the interrupt service program is called in response to the timer capture event, calculating an actual period value of the tested signal according to the current accumulated overflow times and the capture period value, and resetting the accumulated overflow times. According to the embodiment of the invention, the period is calculated through the cumulative counting of the timer overflow events and the counting of the timer capture events, and the problem that the timer is limited by digits and cannot give consideration to low-frequency band width period coverage and measurement precision is solved.

A method for controlling an analog-digital converter comprising first and second oscillators, and first and second elements, the method comprising a first step during which the first and second oscillators generate frequencies depending on an electrical characteristic of the first element and of the second element, respectively, and a second step during which the first and second oscillators generate frequencies depending on the electrical characteristic of the second element and of the first element, respectively.

The utility model provides a voltage frequency monitoring alarm system. The system comprises a control module, and a monitoring input module, a buzzing alarm module, a light indication module and a power supply module which are connected with the control module, wherein the power supply module supplies power to the monitoring input module, the buzzing alarm module and the light indication module at the same time. According to the invention, the current transformer unit senses the frequency change of the voltage to be monitored, the photoelectric coupler unit is utilized to form the DC pulse voltage for the control module to carry out frequency monitoring, and the buzzing alarm module and the light indication module are further combined to realize the acousto-optic display of the frequency monitoring result. By using a simple system structure, rapid and effective output voltage frequency monitoring can be realized, the condition that the voltage frequency is unstable can be reflected in time, and the downstream equipment fault problem caused by voltage frequency fluctuation can be prevented.

The application provides a frequency standard measurement method, device, computer equipment and storage medium, the method comprises: frequency source output measurement signal is carried out frequency division processing, obtains low frequency pulse signal; using high-precision time interval counter to low frequency pulse signal is carried out delay measurement and time interval counting, and is output in the form of time stamp; by setting a sliding window, using sliding average algorithm to time stamp is carried out sliding average filtering processing, all time stamps are carried out sliding difference to obtain time difference, time difference is grouped according to order and is taken average in group to obtain average time difference; by increasing the length of the sliding window, the number of samples is increased to reduce the statistical error; using average time difference, calculate frequency measurement value, relative frequency deviation and allan variance. The method of the application increases the sliding window, and the frequency measurement result obtained by the algorithm of grouping and averaging the time difference has higher measurement precision and stability.

The invention belongs to the technical field of primary and secondary fusion pole-mounted switch signal measurement assembly protection, and particularly relates to a primary and secondary fusion pole-mounted switch signal measurement device and method. Comprising an EMC filtering protection module connected with a pole-mounted switch, a secondary signal analog quantity AD sampling module, a frequency measurement module, a power supply module, a state quantity detection module and a signal processing coding module. The EMC filtering protection module is respectively connected with the secondary signal analog quantity AD sampling module, the frequency measurement module, the power supply module and the state quantity detection module, and the secondary signal analog quantity AD sampling module, the frequency measurement module and the state quantity detection module are all connected with the signal processing coding module. According to the technical scheme provided by the invention, the device has the capability of independently carrying out related electromagnetic compatibility (EMC) tests, is relatively high in anti-interference performance, is not easy to damage, and is more suitable for a complex power grid operation environment, so that the reliability of the device is improved, the maintenance cost is reduced, and meanwhile, the signal acquisition precision is also improved.

The embodiment of the invention discloses a clock signal frequency detection circuit. The circuit comprises a first edge pulse generator, a first latch, a switch module, a time length comparison module and a second edge pulse generator. The first edge pulse generator is used for generating a first clock edge pulse signal according to the edge of a to-be-tested clock signal; the first latch is used for receiving a first clock edge pulse signal and generating a first control signal according to the first clock edge pulse signal; the switch module is switched on or switched off according to the first control signal; the time length comparison module is used for comparing the period of the first clock edge pulse signal with reference time and outputting a comparison result; the second edge pulse generator is used for generating a second clock edge pulse signal according to the edge of the comparison result. According to the technical scheme provided by the embodiment of the invention, the time length comparison module is opened at the edge of the to-be-detected clock signal and closed after comparison, so that low-power-consumption clock signal frequency detection is realized.

A clock monitoring circuit includes a clock enable signal generator configured to generate an ultra-high frequency clock enable signal based on a clock enable control signal and a reference clock signal, and an ultra-high frequency detector configured to generate an ultra-high frequency determination signal indicating whether a selection clock signal is an ultra-high frequency signal, based on the selection clock signal, the ultra-high frequency clock enable signal, and the reference clock signal.

The invention discloses a batch automatic detection method and system for internal clocks of a chip. The method comprises the following steps: providing a clock frequency measurement module taking a reference crystal oscillator as a reference clock source in a chip, introducing all internal clocks of the chip into the clock frequency measurement module, carrying out frequency test through a software calling module, identifying all the internal clocks by software in a dynamic enumeration mode and carrying out measurement one by one, start and stop of the module can be controlled through the register, and the software plug-in calls a driver in an application layer and generates a test report. The system comprises a reference clock module, a clock frequency measurement module, a measurement control module, a driving module and a software plug-in module. The method and the system do not need to change hardware equipment and a circuit board, do not need to depend on an external measuring tool, are high in detection efficiency, comprehensive in coverage and accurate in result, do not affect normal operation of other functional modules of the chip, and are suitable for chip design verification, communication, computers, consumer electronics and other scenes using system-level chips.

The application provides a kind of wideband electronic reconnaissance signal fine frequency measurement implementation method based on FPGA.The traditional electronic reconnaissance signal frequency measurement method is FFT frequency measurement method, in the face of increasingly complex electronic reconnaissance environment, signal bandwidth gradually increases etc.Situation, using traditional fine frequency measurement method error is larger, real-time cannot be guaranteed.According to the deficiency, the application is based on the demand of wideband electronic reconnaissance signal fine frequency measurement, using the characteristics of FPGA flow processing, a kind of multi-channel parallel fine frequency measurement implementation method based on FPGA is designed, the effectiveness of the method is illustrated by typical wideband electronic reconnaissance signal example, effectively make up for the deficiency of traditional processing method.The application can be used in electronic reconnaissance, electronic countermeasure and radar signal processing field, provide a kind of accurate measurement wideband electronic reconnaissance signal frequency method, with higher frequency measurement accuracy, stronger parallel ability, better real-time characteristics.

A power grid frequency measurement apparatus and method, making the final obtained power grid frequency have both good real-time performance and high accuracy. The power grid frequency measurement apparatus (100) comprises: a synchronous motor (110), configured to be connected to a power grid and rotate under the drive of grid power; and a rotational speed measurement apparatus (120), configured to be connected to the synchronous motor (110) and output a target parameter on the basis of the rotational speed of the synchronous motor (110), wherein the target parameter indicates the power grid frequency.

The invention discloses a method for automatically identifying pi pulse time of a mercury ion microwave clock, which comprises the following steps of: setting a time sequence: performing on-off operation by external equipment according to a specified time sequence; fluorescence signals are collected, and the single-chip microcomputer is used for collecting the fluorescence signals; performing transition probability scanning, setting microwave source dot frequency, microwave action starting time, microwave action stopping time and microwave action time stepping, and performing transition probability scanning in a Rabi mode by using an external reference source as a reference signal to obtain a transition probability scanning curve; and based on the transition probability spectral line, carrying out nonlinear fitting on the data, drawing a new transition probability function curve, solving a new transition probability function derivative, further confirming a pi pulse range, and identifying the pi pulse. The method provided by the invention has the advantages of full-automatic operation, high intelligent identification precision and good system flexibility, the experiment efficiency is improved, and the experiment error is reduced.

The invention discloses a dynamic calibration equal-precision frequency measurement method based on STM32. The method comprises the following steps: initializing a first timer and a second timer; inputting a reference standard signal to a first channel of the first timer, calculating gate time when the reference standard signal is input, and calculating a theoretical count value of a counter of the second timer when the reference standard signal is input; reading the register value of the counter of the second timer after the gate time is ended, and calculating the ratio of the theoretical count value of the second timer to the register value of the counter of the second timer as a correction parameter; inputting a measured signal to the first channel of the first timer, reading the register value of the counter of the second timer, and calculating the frequency of the measured signal in combination with the correction parameter. Counting errors caused by hardware delay errors in the current environment can be dynamically compensated by correcting parameters, the measurement precision of different frequency points is improved, additional capture interruption does not need to be arranged, operation is easy, and the measurement precision is high.

The invention belongs to the field of electric energy meter metering, and discloses a power grid frequency change reactive error compensation method, system and device and a medium, and the method comprises the steps: obtaining frequency values sampled by a metering chip, splitting the frequency values based on a central point, and obtaining the central point frequency of each frequency value; inputting the central point frequency of each frequency value extracted from the sample table and a pre-configured output frequency into an initial fundamental reactive phase correction register together for processing to obtain a register value of the central point frequency; and inputting the frequency values, the central point frequencies of the frequency values and the register values of the central point frequencies into a fundamental wave reactive phase correction register for calculation to obtain a meter calibration parameter checksum, and storing the meter calibration parameter checksum to realize dynamic reactive error compensation. According to the method, the phase correction register is dynamically corrected through a statistical method in combination with a software algorithm, the reactive error of the reactive primary table can be kept within an ideal range within a power grid frequency range, and the energy metering accuracy is improved.

To provide a frequency delta-sigma modulation signal output circuit capable of generating a frequency delta-sigma modulation signal with reduced noise components.SOLUTION: A frequency delta-sigma modulation signal output circuit includes: a phase modulation circuit that generates a phase modulation signal by generating n delay signals by delaying a signal under measurement, where n is any integer greater than or equal to 2, and randomly selecting one of the n delay signals in synchronization with the signal under measurement; and a frequency ratio digital conversion circuit that generates a frequency delta-sigma modulated signal using a reference signal and the phase modulation signal.SELECTED DRAWING: Figure 1

This invention provides a temperature-monitored field stabilization method and system, relating to the field of permanent magnet magnetic resonance (PMMR). The method acquires temperature data from a magnet and simultaneously measures the proton resonance signal frequency using a magnetic resonance probe to obtain temperature-frequency data. The data is preprocessed and feature extracted, and a specially tuned feature extraction neural network and a time-series analysis neural network structure are introduced to construct a nonlinear mapping model between the spatiotemporal distribution of the temperature field and frequency drift, enabling frequency prediction. A Z0 compensation coil then generates a compensation magnetic field to fine-tune the magnetic field. This invention significantly reduces frequency drift caused by ambient temperature fluctuations without requiring a complex hardware platform, compressing the drift from hundreds of Hz to the order of several Hz. This effectively improves the testing accuracy, long-term stability, and repeatability of permanent magnet PMMR systems, and is applicable to scenarios such as permanent magnet PMMR analysis instruments, permanent magnet magnetic field control systems, and long-term online monitoring equipment.

The embodiment of the invention provides a power grid frequency measurement device and method. The finally obtained power grid frequency is good in real-time performance and high in accuracy. The device for measuring the frequency of the power grid comprises a synchronous motor which is configured to be connected to the power grid and is driven by the power of the power grid to rotate; and the rotating speed measuring device is configured to be connected with the synchronous motor and output target parameters according to the rotating speed of the synchronous motor, and the target parameters indicate the power grid frequency.

In an implementation, a method may include receiving an input clock at an input pin of a device, the device having a Joint Test Action Group (JTAG) test access port (TAP). The method may also include counting a first number of cycles of a reference clock using a first counter. The method may furthermore include simultaneously counting a second number of cycles of the input clock received at the input pin using a second counter. The method may in addition include calculating a frequency of the input clock based on the counted first number of cycles of the reference clock, the counted second number of cycles of the input clock, and a frequency of the reference clock.

The application aims to provide a FPGA-based adaptive frequency measurement device and test method with higher adaptability, multiple measurement ranges, improved measurement accuracy and controlled measurement time. The application comprises a high-speed voltage comparator, a FPGA frequency measurement module and an operation unit connected in sequence, the high-speed voltage comparator is connected to a measured signal, the high-speed voltage comparator converts the measured signal into a digital pulse, the FPGA frequency measurement module performs measurement counting to obtain a counting result of the measured signal and a reference clock counting result, and the operation unit calculates the frequency of the measured signal. The application is applied to the technical field of digital frequency measurement.

The invention belongs to the field of signal processing. The invention provides a pulse frequency measurement method which comprises the following steps: S1, sampling a single-frequency pulse in a gating window to obtain a sequence X (n) = Asin [2pifTn + theta] (n = 0, 1,... N-1); x (n + 1) = Asin [2pifT (n + 1) + theta]; s2, constructing difference of adjacent points to obtain two paths of quantities U (n) = X (n + 1) + X (n) = 2Acos [2pifTn + theta + pifT] sin (pifT); v (n) = X (n + 1)-X (n) = 2Asin [2pifTn + theta + pifT] cos (pifT); and S3, determining that the change of the current phase along with time is a straight line, wherein the slope is predicted frequency f0.

The invention belongs to the technical field of frequency division, particularly relates to a programmable automatic frequency division device and method based on a field programmable gate array, and aims to meet the requirements of precision and high efficiency of clock frequency division in a complex electronic circuit scene. In the programmable automatic frequency division device, a first programmable frequency division chip and a second programmable frequency division chip are arranged in a cascade mode, the input end of the first programmable frequency division chip is used for receiving a signal to be subjected to frequency division, the output end of the second programmable frequency division chip is connected with the input end of a shunt chip, and a first fixed frequency division chip and a second fixed frequency division chip are arranged in a cascade mode. The input end of the first fixed frequency division chip is connected with the second output end of the shunt chip, and the output end of the second fixed frequency division chip outputs a frequency measurement feedback signal; the frequency measurement module is connected with the output end of the second fixed frequency division chip, and receives and measures the frequency of the frequency measurement feedback signal; the control module is connected with control pins of the first programmable frequency division chip and the second programmable frequency division chip, and sends configuration signals to the two programmable frequency division chips to adjust the frequency division ratio.

The utility model provides a dual-channel digital frequency meter, and belongs to the technical field of digital frequency meters. Comprising a single-chip microcomputer, a display circuit and a power supply circuit used for supplying power, the system also comprises a first signal shaping circuit, a first relay switch K1, a first frequency divider circuit, a second relay switch K2, a second signal shaping circuit, a third relay switch K3, a second frequency divider circuit, a fourth relay switch K4, a multivibrator circuit used for outputting a preset gate signal, and a gate control circuit. According to the dual-channel digital frequency meter, dual-channel measurement can be achieved, two paths of signals can be measured and compared at the same time, and the requirement for simultaneous detection and analysis of different signals in more complex scenes is met.

To provide a frequency monitoring device and a frequency monitoring method for further improving the detection accuracy of an overfrequency in an AC fundamental wave frequency.SOLUTION: The frequency monitoring device includes a frequency detection unit, a frequency / period conversion unit, a filter unit, a period / frequency conversion unit, and an overfrequency detection unit. The frequency detection unit calculates a first estimated frequency of the AC component within a predetermined period. The frequency period conversion unit calculates a period by a reciprocal operation on the first estimated frequency. The filter unit calculates a value in which the fluctuation of the period is reduced. The period frequency conversion unit calculates a second estimated frequency by a reciprocal operation on a value obtained by reducing the variation of the period. The overfrequency detection unit determines the second estimated frequency on the basis of a predetermined determination criterion defined to detect an overfrequency.SELECTED DRAWING: Figure 4

The embodiment of the invention relates to electronic equipment, a wireless charger and a method for operating the electronic equipment. The present disclosure relates to an apparatus comprising: an inductive element and a first capacitive element connected in series between a first node and a second node; a first MOS transistor connected between the first node and a third node configured to receive a reference potential, the second node being coupled to the third node directly or via a second MOS transistor; a second capacitance element connected between the fourth node and an interconnection node, the interconnection node being located between the first capacitance element and the inductance element; a current generator configured to supply an AC current to the fourth node; and a switch connected between the fourth node and the third node.

The present disclosure provides a motor reciprocating frequency measuring device and a motor testing system. The motor reciprocating frequency measuring device comprises a rotating module capable of being circumscribed by a motor and reciprocating rotation under the driving of the motor; a swinging module with a fixed end and a swinging end, wherein the swinging end is in contact with an initial position on the notch of the rotating module in the initial state, and the swinging end is driven to reciprocate around the fixed end when the rotating module rotates and triggers the counting module when swinging to a predetermined position, and the swinging end returns to the initial position and stops swinging after the rotating module stops rotating; the counting module can count when triggered by the swinging module to obtain the number of swings of the swinging module, so as to obtain the reciprocating frequency of the motor through the number of swings of the swinging module.

The utility model discloses a simulation design device for pulse frequency measurement, which comprises a bottom plate, a machine body is arranged on the upper portion of the bottom plate, a telescopic groove is arranged in the machine body, a telescopic column is arranged in the telescopic groove, an equipment box is arranged on the upper portion of the telescopic column, and a control host and a storage battery are arranged in the machine body. And a pulse counter, an oscilloscope, a frequency meter and auxiliary equipment are arranged in the equipment box. The pulse counter, the oscilloscope, the frequency meter and the auxiliary equipment are integrated in the equipment box, the equipment connection is simplified, the operation complexity is reduced, the equipment box is installed on the machine body through the telescopic column and the telescopic groove, the height of the equipment box can be adjusted according to needs, and the use flexibility is improved. And a wiring seat and a wiring hole are arranged in the equipment box and are used for connecting a pulse counter, an oscilloscope, a frequency meter and auxiliary equipment, so that the connection process between the equipment is simplified.

In an implementation, a method may include receiving an input clock at an input pin of a device, the device having a Joint Test Action Group (JTAG) test access port (TAP). The method may also include counting a first number of cycles of a reference clock using a first counter. The method may furthermore include simultaneously counting a second number of cycles of the input clock received at the input pin using a second counter. The method may in addition include calculating a frequency of the input clock based on the counted first number of cycles of the reference clock, the counted second number of cycles of the input clock, and a frequency of the reference clock.