76 results about "Network time synchronization" patented technology

The present invention discloses a method and device for transmitting network time synchronization messages applicable to any channel environment, including: classifying the data bits of the time synchronization messages to be transmitted to obtain public information bits and secret information bits, and performing Polar coding on the data of the time synchronization messages to obtain a first coding sequence; dividing all data subcarriers within the transmission bandwidth into sub-blocks according to the number of legitimate receivers, and dividing each sub-block to obtain clusters, performing IM modulation on each cluster to determine the active subcarrier indices of each cluster; interleaving the symbol vector obtained by modulating the first coding sequence based on the total frequency-domain channel matrix characteristics of a preset channel simulation system; modulating the interleaved symbol vector onto the active subcarriers selected for each sub-block to complete OFDM-IM modulation, and sending the modulated OFDM-IM signal to each legitimate receiver. The present invention solves the problems of poor security and limited application scenarios in the transmission of network time synchronization messages.

The invention discloses a network time synchronization method, device and equipment and a computer program product, the network time synchronization method is executed by a network time synchronization system, the network time synchronization system comprises a plurality of network nodes, and each network node is equipped with an independent clock source. The network time synchronization method comprises the following steps: receiving a time signal generated by a clock source on each network node; screening the received time signals generated by each clock source to obtain screened time signals; based on the screened time signals, determining an optimal time reference by using a preset multi-clock combination synchronization algorithm; and correcting a local clock of the network node according to the optimal time reference. Through multi-clock combination and a collaborative synchronization mechanism, high-precision time synchronization can be realized without depending on expensive high-precision hardware, the deployment cost is remarkably reduced, the high performance of the system is ensured, and the system adapts to a complex network environment.

The invention discloses a sensor network time synchronization method, which comprises the following steps: firstly, clustering and networking sensor nodes according to equipment to which the sensor nodes belong, and for clusters, fusing clock frequency offset between a quantized master control clock signal and a cluster head node into an improved TPSN protocol to dynamically calibrate a logic clock of the cluster head node; and for the interior of the cluster, calibrating the logic clock of the child node in the cluster based on the clock drift amount and the clock offset amount of the cluster head node and the child node in the cluster. According to the method, the characteristics of a power equipment monitoring scene are combined, and a dynamic hierarchical adjustment mechanism and a bidirectional calibration strategy are introduced, so that the time-varying influence of frequency deviation on the synchronization error can be remarkably suppressed, and the adaptability to network topology change is improved.

The invention provides a wireless ad hoc network time synchronization method, device and system and communication equipment, and relates to the technical field of communication. The wireless ad hoc network time synchronization method comprises the following steps: generating a reference clock signal based on a GNSS (Global Navigation Satellite System) signal of a global navigation satellite system; generating a local clock signal synchronized with the reference clock signal; determining a sending window of the wireless frame according to preset sending time slot configuration; wherein the starting moment of the sending window is set to be deviated from a specified edge of the reference clock signal by a preset time delay; generating and sending the wireless frame in the sending window; wherein the wireless frame at least comprises equipment identification information and time synchronization identification information, and the initial sending time of the wireless frame is consistent with the initial time of the sending window.

Time synchronization distribution in a network may be provided. Time synchronization may be performed by an Access Point (AP) with a plurality of client devices. Next, based on information received from performing the time synchronization with the plurality of client devices, it may be determined that a first client device of the plurality of client devices is a representative client device. Then, for a predetermined time period, time synchronization with the first client device and not with others of the plurality of client devices may be performed. The data associated with the time synchronization with the first client device may be broadcast to others of the plurality of client devices.

The invention provides a method and a system for time synchronization between network devices. The method comprises the following steps: a first network device sends a request message carrying a first timestamp recorded when a port is out to a second network device; receiving a response message carrying the first timestamp, the second timestamp and the third timestamp from the second network equipment, and recording a fourth timestamp when the response message enters the port; and obtaining a mapping relationship between the first network equipment timestamp and the second network equipment timestamp according to the multiple groups of timestamps. According to the method and the device, the mapping relationship between the timestamps of different devices is obtained by using the least square algorithm according to the multiple groups of timestamps obtained according to the interaction message, and the first network device time corresponding to the timestamp of the second network device is obtained by using the mapping relationship, so that time synchronization can be realized without modifying the timestamps of the devices; the problem that when the network equipment has no absolute timestamp and the timestamp does not support modification, the existing time synchronization protocol cannot be used for time synchronization is solved.

This application discloses a network time synchronization verification method, apparatus, electronic device, and computer-readable storage medium. The method includes: sending probe packets to a time synchronization server at a first preset time interval to obtain a round-trip delay sequence within a preset time window; extracting statistical features from the round-trip delay sequence and constructing a network path fingerprint based on the statistical features; obtaining a time offset change when a time synchronization jump or time synchronization request is detected; calculating the fingerprint deviation of the current network path fingerprint relative to the fingerprint baseline; performing consistency matching between the time offset change and the fingerprint deviation, and determining the reliability of the time offset change based on the consistency matching result. This application can distinguish between interpretable offsets caused by normal network fluctuations and uninterpretable offsets caused by link manipulation when a time synchronization jump occurs in the network time synchronization.

This invention relates to a time synchronization method for 5G and TSN converged networks based on a timestamp compensation algorithm, belonging to the field of cross-network time synchronization. It includes: introducing a 5G network as a TSN virtual bridge into the TSN network to form a cross-network, which includes a TSN1 network, a 5G network, and a TSN2 network. The cross-network uses the TSN switches in the TSN1 network as the master clock and the TSN devices in the TSN2 network as slave clocks. Synchronization is achieved by transmitting time synchronization information step-by-step across the NW-TT module, the 5G network clock domain, and the DS-TT module. The cross-network time synchronization includes TSN2 network time synchronization, 5G network time synchronization, and TSN2 network time synchronization. This invention improves the accuracy of time synchronization by calculating the frequency offset and dwell time between NW-TT and DS-TT within the 5G system and performing time compensation in the DS-TT.

Method (300) for providing fault-tolerant network time synchronization in a motor vehicle communication network (100), wherein the motor vehicle communication network (100) comprises: a video controller (115) coupled with a first camera (110) and a second camera (175), a lidar controller (125) coupled with a first lidar transceiver (130) and a second lidar transceiver (120), a radar controller (145) coupled with a first radar transceiver (140) and a second radar (150), a processor (160), a user interface (165), a vehicle controller (155) and a trailer interface (170) the procedure includes the following: Generation of a time synchronization signal; Transmission of the time synchronization signal from a first switch (415) to a second switch (425) via a first connection and from the first switch (415) to a third switch (435) via a second connection; Detecting a connection error on the second connection; and Transmitting the time synchronization signal from the second switch to the third switch (435) via a third connection in response to the connection fault, wherein the time synchronization signal is generated by a radar controller coupled to the first switch, and wherein a first radar sensor is coupled to the second switch and a second radar sensor is coupled to the third switch, wherein the lidar controller (125), the video controller (115) and the radar controller (145) are each configured to receive and process data from their respective sensors, and the video controller (115) is set up to receive images from the first camera (110) and the second camera (175) and to process the images to generate image data for use in creating an object map around the vehicle (105).

The invention belongs to the technical field of avionics, and particularly relates to an architecture design method of a TSN network end system with dual-processor collaboration. The system architecture comprises a main processor and a network card; a buffer A, a register A, a buffer B, a register B, a coprocessor and a protocol conversion module are arranged in the network card; the main processor performs data interaction with a buffer A and a register A in the network card; the coprocessor performs data interaction with a buffer B and a register B in the network card; the protocol conversion module performs data interaction with the buffer A, the register A, the buffer B, the register B and an external network; the main processor is used for receiving an airborne light thunder signal, a sensor signal, an avionics / electromechanical control signal and a graphic video signal, and outputting light thunder sensor data, an avionics / electromechanical control instruction and a graphic video signal; the coprocessor is used for receiving avionics network management data, network time synchronization data and built-in self-inspection data and outputting corresponding data packets.

The invention discloses a sensor network time synchronization method based on local bidirectional correction and related equipment, relates to the technical field of sensor networks, and solves the problem of high overhead of a bidirectional message time synchronization network. According to the method, the communication range is reduced through local bidirectional correction, and the synchronization hop count is reduced through hierarchical division of a topological structure, so that the network overhead is reduced while the overall time synchronization of the sensor network is realized: the reference nodes are dynamically elected to adapt to the network communication quality change, and the time synchronization accuracy is ensured while the network communication quality is improved. And the robustness of the time synchronization method is improved.

The present invention relates to a cross-network time synchronization method for the fusion of AUTBUS and TSN, and belongs to the field of network time synchronization. It aims to solve the problems that traditional Ethernet cannot meet the needs of time-sensitive applications and the TSN network is limited in scale. The method collects and predicts the delay values ​​of each part in the heterogeneous network by placing a time compensation value prediction algorithm in the AUTBUS terminal, and finally compensates the prediction results to the local clock of the AUTBUS terminal to achieve end-to-end time synchronization of the fusion network of AUTBUS and TSN. The method includes four steps: time synchronization within the TSN network, time synchronization within the gateway, time synchronization within the AUTBUS network, and time compensation of the AUTBUS terminal, and predicts the delay data through a linear regression prediction algorithm to improve synchronization accuracy and efficiency. The present invention is applicable to the fields of intelligent manufacturing, industrial automation, etc., and provides an effective solution for time synchronization of heterogeneous networks.

The invention discloses a method and a system for testing synchronous digital quantity injection of a regional stability control system based on network time synchronization, and the method is characterized in that the method comprises the following steps: S1, determining a test case needed by each control strategy function test of the stability control system according to the architecture and functions of the regional stability control system; s2, based on the test state sequence and the test input quantity determined by the test case, automatically generating a stability control system digital quantity injection test script matched with the test state sequence and the test input quantity; s3, through a network time synchronization mechanism, it is ensured that clock references of the test computer systems of all the sites are consistent, triggering time marks of test cases are set in a unified mode, and generated test case scripts are distributed to stability control devices of all the sites; and S4, analyzing the received test case script by the stability control device of each station, and extracting a test state sequence and characteristic parameters related to the station device.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a wireless communication device (WCD) may perform a clock tracking procedure that comprises: transmitting, to an access point (AP), an extended personal area network (XPAN) synchronization message pair that is addressed to a peripheral device associated with the WCD, and receiving, from the AP, an XPAN synchronization response message pair that is associated with the XPAN synchronization message pair. The WCD may transmit, to the AP, user data that is addressed to the peripheral device at a time that is based at least in part on an estimated awake window, the estimated awake window being based at least in part on the XPAN synchronization response message pair. Numerous other aspects are described.

The invention relates to network time service monitoring equipment and method compatible with NTP and PTP, and belongs to the field of network time service monitoring. The system comprises a power supply module, a mother board module, a monitoring module, a receiver module, a clock module, an NTP monitoring module, a PTP monitoring module and upper computer software. The device is comprehensive in function, high in integration level and wide in application field, high-precision real-time monitoring can be carried out on NTP network time service and PTP network time service at the same time, and the blank in the field is filled. In addition, the mother board module is composed of a plurality of vertical slot positions side by side, different modules can be inserted according to needs, and the number of the NTP monitoring modules and the number of the PTP monitoring modules can be configured.

The present invention discloses a virtual cluster time synchronization method based on PCIe passthrough, belonging to the technical fields of virtualization and network time synchronization. First, based on the PCIe passthrough technology, the virtual cluster nodes are bound to the underlying clock card to obtain the underlying physical clock time; then, a soft interrupt signal is generated through a timer to enable the virtual nodes to read the clock information of the underlying physical clock card at the same agreed time, while measuring the timer delay and correcting the time read from the clock card in real time; finally, the clock error between the virtual cluster nodes can be obtained by calculating the physical time values of the two clock cards. The present invention utilizes the high-precision hardware of the clock card and, with the help of the PCIe passthrough technology of the virtual machine, can accurately achieve the measurement of system time synchronization between virtual clusters.

This application discloses a clock synchronization method, apparatus, board, and computer-readable storage medium, relating to the field of network time synchronization technology. The service card encapsulates a device sending timestamp in a first NTP request message sent by the main control card based on the first current service system time to obtain a second NTP request message, which is then sent to the NTP server. Based on the second current service system time, the service card encapsulates a device receiving timestamp in a second NTP response message sent by the NTP server to obtain a first NTP response message. The first NTP response message is then sent to the main control card, allowing the main control card to calculate the network clock deviation between itself and the NTP server based on the first NTP response message, and adjust the main control system time accordingly. This method avoids the problem of large errors between the device sending timestamp and the device receiving timestamp, thus ensuring that the network clock deviation calculated by the main control card will not have significant errors.

The application provides a network time synchronization system and method, and belongs to the technical field of network security. The system comprises a sending end and a plurality of receiving ends. Each receiving end is provided with a physical link between the sending end. The sending end is connected with a secure coding modulator. Each receiving end is connected with a secure demodulation decoder. The secure coding modulator and each secure demodulation decoder are provided with a secure transmission auxiliary device. The secure transmission auxiliary device comprises a first end channel simulation subsystem connected with the secure coding modulator, a second end channel simulation subsystem connected with the secure demodulation decoder, a plurality of channel simulation subsystems and a plurality of secure exchange devices located between the first end channel simulation subsystem and the second end channel simulation subsystem. A special communication link is arranged between the secure transmission auxiliary devices. The application realizes the secure transmission of secret information bits in the network time synchronization message, physical layer identity authentication, physical layer routing control and other functions.

The application provides a physical layer identity authentication method and device of a network time synchronization system, and belongs to the technical field of network security, and specifically comprises the following steps: encoding and modulating a sending end original time synchronization message, and inserting an identity authentication pilot sequence; performing pre-distortion of the message signal related to the sending end identity; performing step-by-step equalization of the message signal by each device based on a pre-measured and stored frequency domain channel matrix of a physical channel; a security demodulator extracts a current sub-block identity authentication pilot sequence, estimates, interpolates and stores the pre-distorted sequence, and then performs frequency domain equalization, demodulation and decoding on the current sub-block data sub-carrier by using the pre-distorted sequence to recover the original time synchronization message and a message security indication vector; identity authentication is judged based on the error code rate of the message security indication vector, and the original time synchronization message is sent to a receiving end or discarded according to the judgment. The scheme of the application effectively overcomes external and internal attackers, and realizes time source identity authentication.

The application provides a time synchronization method and device, electronic equipment, storage medium and computer program product, relates to the technical field of network time synchronization, and the method comprises the following steps: receiving a synchronization message sent by a time server; wherein the synchronization message comprises time data; the time data is used for representing the time delay in a communication path; and time synchronization is performed based on the time data and a receiving timestamp of the synchronization message. The scheme in the embodiment of the application can improve network performance.

The present application discloses a method and apparatus for measuring time synchronization traffic and gating configuration in a time-sensitive network. A test adaptation dictionary is generated, which includes test status parameters and test configuration parameters. Among them, a delay value is determined according to the test status parameters and compared with the gating period to meet the condition of no error window. The test adaptation dictionary is retrieved according to the current test status parameters. If the corresponding test configuration parameter set is matched, the configuration is directly sent to the device under test; if not, a new test configuration parameter set needs to be configured, which includes at least one adjustment operation for a certain queue or multiple queues to ensure the isolation of time synchronization traffic and service traffic in the physical time slot. Whether the test passes is judged according to whether the condition of no error window is met. The present application can solve the problem of insufficient test accuracy caused by the occupation of service traffic by time synchronization traffic.

The present invention discloses a network time synchronization system and method supporting high-precision signals. The system includes: the first and second system core switches are respectively connected to the first and second gigabit switches, the first and second dedicated service 10-gigabit switches; the first and second gigabit switches are respectively connected to the primary and standby time synchronization terminals; the primary and standby time synchronization terminals are connected to the service processing server cluster through their respective corresponding primary and standby gigabit switches to form a 32PPS switching subnet; the first and second dedicated service 10-gigabit switches are respectively connected to the service processing server cluster, the first and second signal transceiver subsystem switches to form a service subnet; the first and second signal transceiver subsystem switches are respectively connected to a plurality of data transceiver devices to form a signal transceiver service subnet. The present invention optimizes the physical topology and improves the service processing flow to ensure the real-time performance and reliability of the time synchronization 32PPS signal, providing a strong guarantee for the Beidou satellite service processing.

The invention relates to a fuzzy multi-layer network time synchronization method with an output coupling characteristic, which comprises the following steps of: constructing a fuzzy multi-layer output network with the output coupling characteristic, and establishing a predefined time stability lemma of a switching type; a controller is triggered based on a fixed time intermittent dynamic event, a synchronization error is defined, a fixed time output synchronization problem of a fuzzy multilayer network with an output coupling characteristic is solved, a fixed time output synchronization criterion is established, and fixed time output synchronization of the multilayer network is realized; and based on the predefined time stability lemma of the switching type, solving the predefined time output synchronization problem of the fuzzy multilayer network with the output coupling characteristic, and establishing a predefined time output synchronization criterion to realize the predefined time output synchronization of the multilayer network. According to the invention, under the condition that the initial value of the node is unknown, the fixed / predefined time is synchronized by using the node output information.

This invention discloses a universal time synchronization method and device for digital twin networks. Based on a synchronization strategy based on two-way message exchange, the method modulates synchronization information for scenarios where the two-way delay is fixed, linear, or nonlinear. Multiple measurements are performed to collect multiple sets of synchronization data, which are then demodulated to achieve high-precision time synchronization. This method extends high-precision time synchronization from static networks to general networks, offering a wider range of applications than traditional network time synchronization methods targeting fixed transmission delays, and can achieve high-precision time synchronization.

The invention discloses a wireless network time synchronization method and system, and a storage medium, and the method comprises the steps: collecting network node time data, forming an original sampling sequence, and generating a whole network clock observation matrix; based on the connection strength between each pair of network nodes, constructing a Laplacian matrix; on the basis of an objective function of a graph regularization robust low-rank decomposition model, carrying out joint optimization solution on the whole-network clock observation matrix, and alternately updating a low-rank matrix and a sparse matrix; after convergence conditions are met, drift and offset correction values are calculated, and correction parameters are generated; and performing wireless network time synchronization according to the correction parameter. The problem that an existing synchronization algorithm is unstable in precision under the conditions of strong interference, packet loss and dynamic topology is solved, and unification of high precision and high robustness of clocks of the whole network is achieved.

The invention discloses a clock signal compensation method, and relates to the technical field of network time synchronization, and the method comprises the steps: detecting a program operation state of a first synchronization program; under the condition that the program running state is used for indicating that a first clock signal synchronized by the first synchronization program for the network equipment has clock signal deviation, generating a clock compensation parameter for the first synchronization program according to the first clock signal and a second clock signal synchronized by the second synchronization program for the network equipment, obtaining a target deviation parameter of the first synchronization program; the first clock signal is compensated according to the clock compensation parameter and the target deviation parameter, the target clock signal is obtained, the network device is used for executing the to-be-operated service through the target clock signal, the technical problem that in the related technology, the time synchronization efficiency of the network device is low is solved, and the time synchronization efficiency of the network device is improved. The technical effect of improving the time synchronization efficiency of the network equipment is achieved.

This invention relates to the field of network time synchronization technology, and discloses a network time synchronization method, system, storage medium, and electronic device for bypassing UDP port blocking. The method includes: sending a time synchronization request to a Network Time Protocol (NTP) server through a User Datagram Protocol (UDP) port to detect the reachability of the NTP primary channel; when the NTP primary channel is determined to be unreachable, generating a query domain name containing a first time parameter to form a Domain Name System (DNS) query message encapsulating the time synchronization request; constructing a DNS secure transmission backup channel and sending the DNS query message to the target server; receiving the DNS response message returned by the target server and extracting a second time parameter from it; calculating the clock offset between the client and the target server based on the first and second time parameters, and adjusting the local system clock accordingly; the above method achieves secure and reliable network time synchronization under UDP port blocking.

The present invention relates to a network time synchronization method, belonging to the field of communication network technology. The method comprises: maintaining a master port vector table within each node, wherein the table records the maximum clock drift rate and maximum clock drift amount of all nodes under each master port; each node completes the master port vector table initialization according to the synchronized status message; when the synchronization time arrives, the root node updates the master port vector table and selectively sends a synchronization message; the slave node receives the synchronization message, synchronizes its own time and updates its own clock drift rate; and simultaneously replies a status message to the parent node along the slave port to notify its own clock drift rate; after receiving the status message, each node updates its own master port vector table and selectively notifies the parent node. The method of the present invention solves the problems of the prior art time synchronization message having large overhead, resulting in additional bandwidth consumption, and time-sensitive services conflicting with time synchronization signaling messages.

The invention provides a cross-network time synchronization method, device and equipment in a smart power grid, and relates to the technical field of time synchronization. The method comprises the following steps: acquiring electrical operation data in a transformer substation in a target smart power grid, link characteristic data in a cross-network transmission link system, a Beidou time service signal and a power grid time signal of the target smart power grid; unifying the initial time of each link according to the Beidou time service signal, the power grid time signal and the link characteristic data, and obtaining an initial deviation calibration table; according to the initial deviation calibration table, the electrical operation data and the link characteristic data, constructing a multi-link cooperative time delay model; according to the link feature data, the electrical operation data and a multi-link collaborative delay model, obtaining delay prediction data of each link; and each link is calibrated based on the time delay prediction data, so that the cross-network time in the target smart power grid is synchronized. According to the invention, integrated time synchronization management of multiple types of transmission networks can be realized.

The invention discloses a low-voltage carrier multi-configuration network time synchronization collaboration method, which is characterized in that network nodes are divided into a plurality of logic communication groups, and a periodic synchronization reference frame and a time slot distribution mechanism are adopted, so that intra-group high-precision synchronization and cross-group seamless forwarding are realized; by adopting the method, the synchronization precision is remarkably improved, and the reference node periodically broadcasts the synchronization frame and compensates the transmission delay, so that the clock skew of each node is reduced to be below millisecond level; flexible configuration and rapid reconstruction capability are realized, dynamic increase and decrease of nodes and real-time update of configuration are supported, manual intervention is not needed, and configuration switching time delay is less than 20 milliseconds; communication is high in reliability, time slot isolation reduces inter-group conflicts, and a cross-group forwarding mechanism ensures that the data transmission success rate is high; the compatibility is strong, the deployment is easy, only a synchronization frame and time slot mapping need to be added in an existing PLC link layer protocol, and primary equipment of a power grid does not need to be changed; the operation and maintenance cost is reduced, and the operation efficiency and stability of the power distribution network communication system are improved.