356 results about "Slave clock" patented technology

The invention discloses a clock tree synthesis method and related equipment, and the method comprises the steps: dividing a plurality of time sequence units which need to receive clock signals from a clock source into clustering clusters of different levels, and enabling the load capacitance of each clustering cluster of the same level to be balanced; according to a hierarchical sequence of clusters starting from the clock source, taking each cluster as a node of a clock tree, recursively constructing the clock tree, and inserting a target buffer at the position of each node for driving the corresponding node; analyzing the delay and offset of the constructed clock tree to obtain an analysis result; and if the analysis result indicates that the delay and offset of the clock tree do not meet the preset constraint condition, adjusting the clock tree until the adjusted delay and offset of the clock tree meet the preset constraint condition. According to the technical scheme, power consumption and offset can be effectively reduced, calculation efficiency and design reliability are improved, and the method is suitable for high-performance chip design under the advanced technology.

In various examples, sets of correlated timestamps are sampled from clock sources. The sets of correlated timestamps are used to compute translation data, such as offsets and / or rates of change of the clock sources. The offsets and / or rates of change may be used to translate a timestamp to a reference time domain. The sampled clock sources may be frequency locked and the translation may be performed without using the rates of change. For example, a running average of the offsets may be used to perform the translation. The translated timestamps and corresponding sensor measurements may be provided to one or more applications for use in performing one or more operations for a machine, such as perception and / or control operations.

The present invention discloses a method, device, equipment, medium and product for clock synchronization between clusters. The method is applied to a slave clock synchronization system in each cluster, and the slave clock synchronization system includes: a clock synchronization module and a calculation module; the clock synchronization module obtains the timestamp of the high-precision time synchronization protocol PTP message between the master clock server and the master clock server, and sends the timestamp to the calculation module; wherein the PTP message includes at least: a synchronization message, a follow-up message, a delay request message and a delay response message; the calculation module determines the corresponding master-slave clock deviation and transmission delay according to the received timestamp, and sends the clock synchronization signal determined according to the master-slave clock deviation, transmission delay and the local slave clock to the clock synchronization module; the clock synchronization module generates the corresponding slave clock second pulse according to the clock synchronization signal sent by the calculation module to complete the slave clock correction. This scheme can realize accurate clock synchronization between computing clusters in a multi-computing cluster system.

The invention relates to a cross-domain clock synchronization method in a time sensitive network, and belongs to the technical field of time synchronization. The method comprises the following steps: establishing a multi-domain clock synchronization network topology based on a transit clock; the transit clock obtains main clock time according to the main domain synchronization message, carries out link delay measurement message interaction with adjacent equipment, records a corresponding timestamp and obtains link delay; transmitting the acquired main clock time, each timestamp and link delay to a synchronization error compensation prediction module in the transfer clock, calculating a clock time offset result by the synchronization error compensation prediction module, and predicting error compensation; frequency and phase adjustment is carried out on a local clock according to the calculated error compensation predicted value, a slave domain synchronization message is sent to adjacent slave clock equipment, and forwarding of the slave domain synchronization message and clock correction are carried out in sequence. According to the invention, accumulated errors such as jitter, time delay change and network congestion can be eliminated as much as possible.

A method and a network device are disclosed for precision time protocol (PTP) clock synchronization. According to an embodiment, a network device determines first estimates of offsets between a slave clock of the network device acting as a PTP slave and a master clock of a PTP master, based on timestamps related to PTP messages communicated between the network device and the PTP master. The network device determines whether there is a change in at least one of a first path from the network device to the PTP master and a second path from the PTP master to the network device. When determining that there is a change in at least one of the first path and the second path, the network device updates the first estimate of the asymmetry based on the first estimates of the offsets.

The invention relates to the field of communication, and discloses a vehicle-mounted network time synchronization method and system, and the method comprises the following steps: a master clock periodically broadcasts a synchronization message to all slave clocks in a network, and the synchronization message comprises a current timestamp; the slave clock receives the synchronization message and records the receiving time T1; the slave clock sends a delay request message to the master clock, and the sending time T2 is recorded; after receiving the delay request, the master clock sends a delay response message and records delay request message receiving time T3; the delay response message comprises a timestamp T4 when the master clock receives the delay request message; and the slave clock obtains network transmission delay and clock skew Offset between the slave clock and the master clock according to the time T1, T2, T3 and T4, and the slave clock adjusts the time according to the clock skew. According to the invention, the time height of each node in the system can be ensured to be consistent. According to the invention, by using clock synchronization mechanisms such as IEEE1588 and the like, the timestamp is ensured to be accurate to the nanosecond level.

The invention discloses a time calibration method and system for a time synchronization network, and relates to the technical field of communication, and the method comprises the steps: installing a clock on each node in the network; time calibration of a master clock is realized by receiving signals of at least two navigation satellites and calculating a time difference between the satellites; message exchange is carried out between the master clock and the slave clock through a network; calculating network delay and clock offset between the master clock and the slave clock; constructing a transparent clock model, recording delay time passing through each node in a message, and performing compensation when network delay is calculated; dynamically selecting a path with lower network delay to perform message exchange between the master clock and the slave clock; and optimizing the clock skew between the master clock and the slave clock. The error calculation module and the error optimization module are arranged to eliminate the uncertainty of most of network delay and message exchange, so that the time synchronization precision is improved, and the long-term stability of synchronization is improved.

The invention discloses a synchronization method and device for time synchronization of a network system, and relates to the technical field of computers, and the method comprises the following steps: when a master station sends a dynamic compensation synchronization frame, recording a compensation sending timestamp in a sensing identification field of a sending end; when the frame is received and transmitted from the station, the identification field is sensed at the port to determine a compensation receiving timestamp and a compensation transmitting timestamp. And the slave station identifies the dynamic compensation synchronization frame after reverse return, calculates dynamic compensation time information based on the compensation receiving timestamp and the compensation sending timestamp corresponding to the slave station, and reads and writes the dynamic compensation time information to a corresponding field. And the master station analyzes the returned dynamic compensation synchronization frame, aggregates the dynamic compensation time information of each slave station, and solves the dynamic compensation values of the master and slave stations in combination with the fixed link delay. And the master station corrects a local high-precision clock according to the data, and writes a compensation value into a local time correction register of the slave station to trigger a hardware counter to correct so as to complete synchronization of the master and slave clocks. By realizing dynamic residence separation, the problem of overlarge error is solved.

The invention provides a time synchronization method based on an IEEE 1588 protocol, and relates to the technical field of time synchronization. Comprising the following steps: firstly, establishing a network-based master-slave clock model to characterize a clock frequency; secondly, acquiring a timestamp set of master and slave clocks of the current round, and calculating average transmission delay and time offset; thirdly, a clock synchronization equation of Kalman filtering is built based on a clock model, time offset and drift serve as input, an optimal time offset value is obtained, and a local clock is adjusted to complete synchronization of the current round. Then, a new timestamp set is obtained for the next round, the average transmission delay and the time offset are calculated, and the optimal offset value is determined through a Kalman filtering equation; meanwhile, the number of cycles is calculated according to the offset value and the receiving timestamp, and frequency compensation is carried out on the slave clock. According to the invention, the problem of low time synchronization precision in the prior art is effectively solved.

The invention discloses a wireless communication system and method based on an EtherCAT network. The system comprises a wireless gateway and a wireless slave station, the wireless gateway comprises an EtherCAT slave station module, a wireless communication module, a control module and an auxiliary function module. The control module carries out packaging conversion on an EtherCAT frame received by the EtherCAT slave station module and a wireless frame of the wireless communication module through hardware-level protocol conversion; the wireless communication module is an FHSS module or a WiFi module. The auxiliary function module comprises a timestamp module for recording time information and is used for assisting the control module to perform master-slave clock synchronization by adopting a multi-stage distributed clock synchronization optimization algorithm; the wireless slave station comprises an EtherCAT slave station module, a wireless communication module and a local control unit, wherein the EtherCAT slave station module is used for receiving the control instruction of the EtherCAT master station and is compatible with the wireless gateway; the wireless communication module is used for uploading a wireless frame packaged with an EtherCAT sub-message and has the same model as the wireless frame; and the local control unit is used for analyzing the control instruction of the EtherCAT master station to collect local data and packaging the local data into the EtherCAT sub-message. According to the invention, requirements of industrial automation on high-precision and high-reliability wireless communication can be met.

The invention relates to the technical field of clock synchronization, in particular to a clock synchronization method of a master station system based on EtherCAT, which comprises the following steps: when a master station periodically sends time synchronization frames to all slave stations, collecting slave station feedback time data, respectively calculating a clock offset value between master time and slave time, and simultaneously, calculating a clock offset value between the master time and the slave time; constructing a master-slave offset time feature matrix according to the collected multi-periodic data, extracting initial static offset, an offset fluctuation trend and offset collaboration features among multiple slave stations from the constructed master-slave offset time feature matrix, and determining an initial estimation set according to the extracted features; constructing a master-slave offset prediction set based on the initial estimation set, and performing master-slave clock offset adaptive compensation correction based on the determined master-slave offset prediction set; according to the method, the initial offset estimation set is constructed, the offset trend estimation function is introduced, secondary fitting of the offset sequence of each slave station node is achieved, and it is ensured that the prediction precision is remarkably improved through an error comparison mechanism.

The invention discloses a time synchronization method for network nodes. The method specifically comprises the following steps: determining a master node and slave nodes in a network; and periodically detecting the frequency offset rate Rf of the slave clock relative to the master clock and the transmission delay Nddelay between the master node and the slave node, and correcting the current timestamp of the slave clock based on the current timestamp of the master clock to realize the synchronization of the slave clock and the master clock. The master clock with high clock precision is arranged in the network, and the time of the slave clock is regularly calibrated based on the master clock, so that the basic synchronization of the clocks of the nodes in the network is maintained, and the cost required for maintaining the basic synchronization of the network clocks is relatively low.

Systems and methods for supporting multiple data rates are presented. A method includes generating a clock signal from a clock source, serializing, by an analog serializer, a data stream in response to the clock signal to output N data in parallel, coupling a pulse generation circuit to the clock signal, wherein a first switch and a second switch electrically communicate with the pulse generation circuit, and coupling a multiplexer to the pulse generation circuit, wherein the multiplexer receives the N data from the analog serializer and selects a subset of the N data when switching operation of the electronic circuit from a first mode to a second mode.

The invention discloses time-synchronized sensor data for robotic systems and applications. In various examples, a set of related timestamps is sampled from a clock source. A set of related timestamps is used to compute conversion data, such as an offset and / or rate of change of a clock source. The offset and / or rate of change may be used to convert the timestamp to the reference time domain. The sampled clock source may be frequency locked, and the transitions may be performed without using the rate of change. For example, the running average of the offset may be used to perform the transition. The converted timestamps and corresponding sensor measurements may be provided to one or more applications for performing one or more operations of the machine, such as perceptual and / or control operations.

The invention discloses a filtering adjustment method and system based on an adaptive clock, and relates to the technical field of filtering adjustment, and the method comprises the steps: carrying out the time domain framing processing of a collected input signal through employing a sliding window, and combining DCT and compressed sensing to reconstruct the signal, and the main frequency of the signal and the dynamic change of the main frequency in the time sequence are accurately extracted through FFT, Gaussian pyramid layering and a multi-scale optical flow method, so that the frequency identification capability of the non-stationary signal is effectively enhanced, the frequency spectrum resolution is ensured, the data processing amount is remarkably reduced, the response speed of the signal frequency change is improved, and the method is suitable for popularization and application. Through the main-sub clock structure, the quick response of the center frequency of the filter to the change of the main frequency is ensured, the selectivity of the filter and the signal fidelity are improved, through the compensation adjustment of environmental factors, the influence of temperature and voltage changes on signal processing can be effectively reduced, and the robustness and stability of the system are enhanced.

The invention discloses a power grid time frequency change trend prediction method and system based on intelligent electric meter data fusion, and the method comprises the steps: measuring the network transmission delay and time deviation between a master clock and a slave clock of a power grid, obtaining an initial time frequency deviation sequence, carrying out the error calibration, carrying out the data fusion after time domain alignment, and carrying out the prediction of the time frequency change trend. Generating a fusion time sequence; performing recursive estimation on the fusion time sequence, outputting an optimal time frequency deviation sequence, and performing synchronous estimation to obtain a clock phase error, a frequency error and frequency drift as state characteristic quantities; and training a preset machine learning prediction model by taking the optimal time frequency deviation sequence as a supervision signal and taking the state characteristic quantity of the corresponding moment as input, and obtaining a prediction result of the power grid time frequency change trend in the future period based on the trained time frequency change trend prediction model. According to the method, the power grid time synchronization precision and prediction capability are remarkably improved, and reliable technical guarantee is provided for stable operation of a power system.

The invention relates to the field of data acquisition, in particular to a multi-sensor integrated special vehicle modular data acquisition device and system, the device comprises a switch, and a master clock module, a plurality of slave clock modules and a task computer which are respectively connected with the switch, and the master clock module is used for tracking the frequency and time of a GNSS (Global Navigation Satellite System) satellite; the plurality of slave clock modules are synchronized with the master clock module, each slave clock module comprises a trigger controller and an inertial measurement unit, and the plurality of slave clock modules form a distributed clock and are used for coordinating and accurately triggering a plurality of sensors and realizing hardware triggering or capturing a hardware timestamp on each sensor; the task computer is used for collecting data of multiple sensors and carrying out consistency calculation on hardware timestamps. Compared with the prior art, the device has the advantages that nanosecond clocks of multiple sensors are accurately synchronized, different trigger sources are adopted for different sensors, and the stability of the acquisition device is improved.

The invention discloses a time sequence synchronization method and system for data fusion of a multi-modal wearable sensor, a terminal and a storage medium. The method comprises the following steps: acquiring an absolute timestamp as a global clock source; taking the global clock source as a master clock of a precision time protocol, configuring the plurality of wearable sensors as slave clocks, and executing multiple rounds of message interaction between the master clock and the slave clocks through the precision time protocol to obtain a timestamp corresponding to each round of interaction; and calculating the current path time delay and the current clock offset according to the corresponding timestamps, carrying out iterative judgment on the current path time delay and the current clock offset according to a preset path time delay threshold value and a preset clock offset threshold value, and determining whether to correct the local clock according to the current clock offset according to an iterative judgment result. The slave clock and the global clock source achieve time sequence synchronization; and after time synchronization is achieved, phase alignment is carried out on the periodic data sampling tasks of the multiple wearable sensors. According to the invention, the time sequence synchronization precision is obviously improved.

The invention relates to a time synchronization method in a passive optical network, a passive optical network system, communication equipment and a computer readable storage medium. According to the method, aiming at the characteristic that two-way transmission in the PON network is asymmetric, a DBA mechanism of the PON network is combined, in the same period, master-to-slave service forwarding time slots are arranged before slave-to-master forwarding time slots, and a determined moment sending mechanism of a slave clock terminal is introduced, so that the influence of different two-way waiting time delays in the PON network on time synchronization can be avoided; and the master clock terminal determines the offset according to the information obtained in the interaction process with the slave clock terminal in combination with the bidirectional time slot difference and the preset duration, and provides the offset to the slave clock terminal, so that time synchronization between the master clock terminal and the slave clock terminal is realized, the time accuracy of each device in the PON network is improved, and the user experience is improved. The problem that a time synchronization mechanism in a current industrial control network is not matched with a PON network forwarding mechanism is solved.

Provided is a method for time distribution in a communication network of a vehicle. The method includes: sending, from a grandmaster to a first slave, a first time stamp taken from a grandmaster clock; generating, at the first slave, a first time tuple including the first time stamp and a second time stamp taken from a first slave clock at the time of receiving the first time stamp; sending, from the first slave to a second slave a third time stamp taken from the first slave clock, a fourth time stamp calculated based on the third time stamp and the first time tuple using a predefined calculation method, and the first time tuple; calculating, at the second slave, a fifth time stamp based on the third time stamp and the first time tuple; and comparing, at the second slave, the fifth time stamp to the fourth time stamp.

The invention provides a clock synchronization method, a multi-axis drive control system and a computer storage medium, and the method comprises the steps: obtaining a clock synchronization signal which is sent by a master station timer and has a matched period at a slave station end, selecting any timestamp in the clock synchronization signal as a reference point, and carrying out the clock synchronization based on the reference point, determining the corresponding position of the reference point in the counting signal of the local timer, mapping the time information of the master station to a local time axis of the slave station, and calculating the phase difference between the corresponding position of the reference point in the counting signal of the local timer and the starting position of the next period of the counting signal of the local timer, and quantizing the real-time deviation of the master and slave clocks, and finally, dynamically adjusting and updating the period of a counting signal of a local timer to eliminate the phase difference, so that the slave station clock period is kept synchronous with the master station, and the time consistency of the action of each slave station in the multi-axis driving system is ensured.

The invention discloses a multi-modal data high-precision time synchronization acquisition system and method based on Syntaclos, and relates to the technical field of time synchronization, the system comprises a target determination module, a time division module, an index establishment module, a state evaluation module and a time synchronization module; the method is technically characterized by comprising the following steps: sending a time synchronization message to slave clock equipment through master clock equipment, extracting time granularity, dividing time partitions, establishing a corresponding time partition index for each time partition, and outputting a prediction index table through a synchronous topology network; determining an initial time partition of the multi-modal data based on the prediction index table, introducing a machine learning model, building a rule engine, analyzing the degree of influence, predicting a next time partition with deviation, marking a time deviation event once, and performing synchronous processing on the detected time deviation event in a Syntacalos synchronization interface; the time synchronization efficiency is improved, and time synchronization errors are reduced.

The invention relates to the technical field of testability design, and discloses an on-chip clock controller and test equipment, the on-chip clock controller comprises a main clock control circuit, the functional clock input end of the main clock control circuit is connected with a phase-locked loop output clock, and the clock output end of the main clock control circuit is connected to a main frequency domain receiving node so as to output a main frequency clock signal to the main frequency domain receiving node; the functional clock input end of the slave clock control circuit is connected with the clock output end of the master clock control circuit, and the clock output end of the slave clock control circuit is connected to a frequency division domain receiving node so as to output a frequency division clock signal to the frequency division domain receiving node; wherein the master clock control circuit and the slave clock control circuit are controlled by external slave enable signals, and a data interaction channel is arranged between the master frequency domain receiving node and the frequency division domain receiving node. By cascading the master clock control circuit and the slave clock control circuit and constructing the data interaction channel, dynamic collaborative testing of the master frequency domain and the frequency division domain is realized, and the problem of delay fault detection of the multi-frequency-domain integrated circuit is solved.

The embodiment of the invention provides a vehicle-mounted network time synchronization method and device, a storage medium and electronic equipment, and the method comprises the steps: carrying out the synchronization processing of each first slave clock according to a first time synchronization message periodically issued by a master clock, so as to achieve the time synchronization between each first slave clock and the master clock; the main clock is a pre-specified clock node in a time domain; under the condition that the master clock is abnormal, a standby clock is determined as a new master clock, and the standby clock is a pre-specified clock node in a plurality of first slave clocks except the master clock in a time domain; and according to a second time synchronization message periodically issued by the new master clock, performing synchronization processing on each second slave clock, so that time synchronization between each second slave clock and the new master clock is realized. The problem that the starting time of a vehicle-mounted sensitive system is long due to the fact that the new master clock node selection and switching process consumes long time in the related technology is solved.

Embodiments of this application provide a clock synchronization method and an apparatus. The clock synchronization method is applied to a slave node. The clock synchronization method includes: receiving a synchronization packet sent by a master node, where the synchronization packet carries a master clock timestamp of the master node; establishing a mapping relationship between a master clock of the master node and a reference timescale of the slave node based on the master clock timestamp and a timestamp corresponding to a reference timescale of the slave node when the slave node receives the synchronization packet; obtaining a time combination of the timestamp corresponding to the reference timescale of the slave node and slave clock time of the slave node, where a collection moment of the reference timescale of the slave node and a collection moment of the slave clock time corresponding to the reference timescale are the same.

Radar System The disclosure relates to a radar system having multiple radar transceiver modules, in which each module has a clock signal that is synchronised with a clock signal generated by a leader transceiver module. Example embodiments include a radar system (400) comprising a plurality of radar transceiver modules (401, 402) mounted to a common PCB (404), the plurality of radar transceiver modules comprising a leader module (401) and one or more follower modules (402), the leader module (401) comprising a first oscillator (403) configured to provide a first clock signal at a first frequency to each follower module (402), each of the leader and follower modules comprising a phase locked loop, PLL, clock signal generator (300), the PLL clock signal generator (300) comprising a divide by n clock divider (304) arranged to output 2n phase shifted clock signals (314) at a third frequency and a multiplexer (306) connected to receive the 2n phase shifted clock signals from the divide by n clock divider (304) and output a third clock signal (308) selected by an input phase select signal (307).

The invention discloses a task synchronization and scheduling method for compensating CAN bus clock drift, which relates to the technical field of industrial automation control, and comprises the following four steps: initializing a system, loading a real-time protocol stack, completing hardware self-inspection and clock calibration, and sending a ready signal after confirming that a link is smooth; performing synchronization parameter configuration and task planning, defining clock synchronization reference parameters, dividing four types of tasks and setting priorities; performing dynamic calibration and data buffering on master and slave clocks, broadcasting a synchronous message with a timestamp by a master station, correcting a local timer by a slave station through a soft phase-locked loop, and constructing an annular buffer area to realize time domain decoupling; task cooperative scheduling and abnormal fault tolerance are carried out, a control task is triggered based on a calibration clock, edge calculation is carried out to reconstruct a motion state and feed-forward compensation is carried out, a multi-dimensional state is monitored in real time, and a fault tolerance mechanism is triggered. According to the method, clock synchronization precision and control stability are greatly improved, bus bandwidth limitation is broken through, high dynamic tracking precision is achieved, and long-term stable operation of the system is guaranteed.

The present techniques relate to voltage droop detection and there is disclosed circuitry for detecting a voltage droop event, the circuitry configured to: receive a clock signal from a clock distribution network; obtain, from a storage, a first predetermined value, a second predetermined value and a predetermined threshold count; obtain one or more measurement values associated with a system voltage; when a first measurement value of the one or more measurement values reaches the first predetermined value, initiate a count of clock cycles until a subsequent measurement value of the one or more measurement values reaches the second predetermined value, the second predetermined value being different from the first predetermined value; and when the count of clock cycles is lower than the predetermined threshold count, cause a control entity to take mitigation action.

The invention provides a method and a system for adjusting clock synchronization of master clock equipment and slave clock equipment in a communication network. The method comprises the following steps: recording timestamp data T1 when the master clock equipment sends a message in a polling period and local time data T2 when the slave clock equipment receives the message sent by the master clock equipment; replacing the local time data T2 of the slave clock equipment by using the timestamp data T1 of the master clock equipment to obtain local replacement time data of the slave clock equipment; obtaining timestamp data associated with the synchronization request message and the synchronization response message of the master clock device and the slave clock device in the polling period; calculating delay data between the master clock device and the slave clock device based on the timestamp data T1 of the master clock device, the local time data T2 of the slave clock device and the associated timestamp data; and performing compensation on the local replacement time data of the slave clock device with the delay data.

The invention discloses a periodic synchronous position interpolation control method and system for a servo driver, and relates to the technical field of servo control, and the method comprises the steps: receiving a synchronous position instruction at a fixed bus period, and recording a theoretical / actual arrival timestamp of the synchronous position instruction; converting the instruction into a position increment and storing the position increment into a buffer; calculating a cache saturation index reflecting instruction stream supply and demand balance in real time; based on the index and the change trend, dynamically calculating and smoothly adjusting a next position loop sampling period through a feedback control model; position loop processing is triggered in the post-adjustment period. According to the invention, by monitoring the instruction stream state and adaptively adjusting local processing, the influence caused by master and slave clock skew and network jitter is compensated, and continuous and uniform instruction input is ensured to be always obtained by a position ring, so that high-stability and high-precision motion control under bus communication is realized, and the anti-interference capability and the synchronization performance of the system are improved.