46 results about "Clock model" patented technology

A method for determining an instantaneous phase difference between time bases of at least two location anchors for a desired point in time (t), each of the location anchors having transmitting and receiving access to a joint broadcast transmission medium and a respective time base for measuring time, wherein a first of the location anchors broadcasts a first broadcast message at least twice; the first location anchor and at least a second of the location anchors receive the first broadcast messages; the second location anchor broadcasting a second broadcast message at least twice; and the second location anchor and at least the first location anchor receive the second broadcast messages. The location server calculates the instantaneous phase difference from a determined first and second clock model functions and from a time elapsed between a reference point in time and the desired point in time t.

A method and apparatus for determining long term orbit (LTO) models using variable time-horizons to improve the orbit and clock model accuracy. The method and apparatus use either historic ephemeris or historic measurements for at least one satellite to produce an orbit parameter prediction model (an LTO model). The parameter predicted by the model is compared to an orbit parameter of a current broadcast ephemeris. The result of the comparison (an indicia of accuracy for the model) is used to establish a time-horizon for the orbit parameter prediction model for that particular satellite. Such a time-horizon may be established in this manner for each satellite within a satellite constellation.

Aspects of a method and system for extending the usability period of long term orbit (LTO) are provided. A GPS enabled handset may receive LTO data from an AGPS server via a wireless communication network such as 3GPP or WiMAX. The GPS enabled handset may be enabled to receive broadcast GPS signals. The GPS enabled handset may extract navigation information from the received broadcast GPS signals to be used to adjust the received LTO data. The usability period of the received LTO data may be extended, accordingly. A clock model and a satellite health model associated with the extracted navigation information may be used to update or replace the clock model and / or the satellite health model of the received LTO data, respectively. A navigation solution for the GPS enabled handset may be determined more accurately based on the adjusted LTO data.

A method and apparatus for determining long term orbit (LTO) models using variable time-horizons to improve the orbit and clock model accuracy. The method and apparatus use either historic ephemeris or historic measurements for at least one satellite to produce an orbit parameter prediction model (an LTO model). The parameter predicted by the model is compared to an orbit parameter of a current broadcast ephemeris. The result of the comparison (an indicia of accuracy for the model) is used to establish a time-horizon for the orbit parameter prediction model for that particular satellite. Such a time-horizon may be established in this manner for each satellite within a satellite constellation.

The invention discloses a synchronous correction method based on an IEEE1588 clock model, and belongs to the technical field of communication. The method comprises the following steps: (1) acquiring the moment point of the IEEE1588 clock model to obtain each timestamp; (2) acquiring the relation between the time of a server and the time of a client through the IEEE1588 clock model, and acquiring the relation among the timestamps in Sync message sending and receiving processes in combination with a PTP (Picture Transfer Protocol); (3) performing difference operation based on the relation among the timestamps; and (4) acquiring the asymmetrical offset of an nth exchange process according to a first-order difference value given in the step (3), moving an average filter through exponential weighting in order that value theta is close to zero, and finishing correction between the server and the client. According to the method, a conventional thought is jumped out, and compensation is performed once again on the basis of the IEEE1588 clock model, so that the problem of end-to-end time non-synchronization is solved, and end-to-end interaction time becomes symmetrical.

The invention provides a GNSS time service performance evaluation method, a GNSS timing receiver is placed in the national time service center, and the satellite broadcasting UTC time is obtained by correcting the pseudo-range output by a receiver through a source tracing model, a satellite clock model, transmitting channel deviation and the receiving end delay or other parameters; meanwhile, theUTC-UTC (NTSC) data which is published by the BIPM T bulletin is utilized to obtain the actual UTC time. The time service error is obtained by the user by comparing the time difference of the satellite broadcasting UTC time and the actual UTC time. According to the method, the time service performance of the single satellite can be evaluated, and the time service performance of the whole satellitestation can be evaluated, so that the systems have comparability, and compatibility and interoperation between the satellite navigation time service systems are supported.

The invention provides a method for time synchronization calibration of a wireless sensor network, wherein the wireless sensor network comprises a plurality of wireless sensor nodes. The method comprises the following steps of: creating a clock model of the wireless sensor nodes to determine clock skew in a local clock of the wireless sensor nodes; estimating optimal state of a standard clock of the wireless sensor nodes by a predetermined filtering mode, and calibrating the clock skew in the local clock; executing linear quadratic optimal control to realize synchronization of the local clock and the standard clock of the wireless sensor nodes. According to the invention, firstly, standard time information received by the nodes is subjected to noise filtering by Kalman filtering, precision of the standard block is improved, and consequently, precision of local time synchronization is improved effectively; then, by a linear quadratic tracking method of optimum control, under premise of ensuring system stability, error is kept around zero with the cost of lower control energy, and the aim of time synchronization is achieved.

An edge clock model is used to capture states from a logic-level simulation of a circuit description. The states are captured at clock edges, or transitions, according to an edge clock model based on a clock specification for the circuit description. The captured states and associated attributes are used in formal verification of the circuit description. This approach helps to reduce or eliminate inaccuracies and other issues with other clock models such as a phase clock model. In one embodiment, a phase clock model can be used in addition to the edge clock model. In another embodiment, the edge clock states can be used to generate states according to different clock models, such as the phase clock model.

The invention disclosed a 220V motor speed-regulation system based on intelligent terminal. The system comprises a CPU master controller, a power module, a clock model, a motor driven module and a communication module, which are connected with the CPU master controller, wherein the communication module inputs the time and speed commands sent from the intelligent terminal to the CPU master controller; the CPU master controller decodes and assigns the commands after accepting time and the speed commands; according to the instructions produced by the CPU master, the clock model control the woke time of the motor; the motor driven module controls the speed of the motor; the power module is utilized for providing power to the motor driven module, the CPU master controller and the communication module. The system brings intelligent terminal in the scope of domestic 220V motor speed-regulation, comprises two ways of manual control and intelligent control terminal, and realizes stepless speed regulating function.

The invention discloses an industrial Internet of Things fault-tolerant time synchronization method and system based on a block chain. The method comprises the following steps of recording data: intra-cluster node time and cluster head node broadcast time,adopting a least square method to construct a cluster node clock model,predicting cluster node time according to the cluster node clock model, calculating the deviation between thecluster head node broadcast timeand the cluster head node prediction timebefore the cluster nodes are synchronized, when the deviation is smaller than a threshold value, enabling the cluster nodes to normally perform time synchronization, or otherwise, enabling the cluster nodes to initiate a consensus request in a broadcast mode,after the nodes in the cluster receive the consensus request broadcast packet, forming a block chain, and sharing time synchronization information of all cluster nodes by initiating a consensus request, broadcasting self time, publishing a result and achieving a consensus mechanism of consensus. The fault-tolerant time synchronization method based on the blockchain consensus mechanism can tolerate f cluster head nodes to fail orbe attacked, and effectively improves the reliability and security of an industrial Internet of Things time synchronization protocol in a complex environment.

Aspects of a method and system for extending the usability period of long term orbit (LTO) are provided. A GPS enabled handset may receive LTO data from an AGPS server via a wireless communication network such as 3GPP or WiMAX. The GPS enabled handset may be enabled to receive broadcast GPS signals. The GPS enabled handset may extract navigation information from the received broadcast GPS signals to be used to adjust the received LTO data. The usability period of the received LTO data may be extended, accordingly. A clock model and a satellite health model associated with the extracted navigation information may be used to update or replace the clock model and / or the satellite health model of the received LTO data, respectively. A navigation solution for the GPS enabled handset may be determined more accurately based on the adjusted LTO data.

The invention relates to a cloud platform simulation system, a cloud platform performance test, computer equipment and a computer readable storage medium. The cloud platform simulation system comprises an application model, a clock model, a load balancer model and a physical equipment model, and when the cloud platform performance test is received, the application model simulates a user to send asimulation user request according to a preset concurrent user number; the load balancer model allocates an executed physical device model to the simulation user request according to the content of thereceived simulation user request; the physical equipment model receiving the simulation user request executes the simulation user request; the clock model records the utilization rate, the response time and the throughput rate of the physical equipment model for executing the simulation user request, and by constructing each model with a simulation actual environment, the performance of the cloudplatform is analyzed more accurately under the condition of not influencing the operation of the cloud platform.

The invention provides a TTE network clock calibration method and system. The TTE network clock calibration system comprises a coarse synchronization subsystem and a fine synchronization subsystem, the coarse synchronization subsystem comprises a synchronization word detection module, a phase synchronization detection module and a coarse synchronization delay modulation module; the fine synchronization subsystem comprises an LMS adaptive filter training module, a coefficient storage module, a drift compensation model module and a fine synchronization delay processing module. A traditional taming crystal oscillator system adopts an analog or semi-digital system and has the defects of high cost, great influence of environmental factors, difficulty in debugging, difficulty in model establishment and the like. According to the time frequency basic principle of the taming crystal oscillator technology, the full-digital taming crystal oscillator system based on the clock model construction technology is designed aiming at the defects of the traditional taming crystal oscillator technology, the system can improve the time difference measurement precision, an advanced crystal oscillator noise model is utilized, analysis and debugging are convenient, and the time difference measurement precision is improved. The tracking capability and the holding capability are better than those of a traditional method.

The invention provides a ground user navigation and positioning method based on a Beidou Ka inter-satellite link signal. The method comprises that it is supposed that between epochs k-1 and k (k=1, 2,3...), a user in an area with a Beidou inter-satellite signal reception terminal in the ground generate inter-satellite link unidirectional range finding values with N different Beidou satellites indifferent time, and N range finding equations are obtained; (2) user positions in the range finding equations are reduced to time Tk in a unified way by using a receiver clock model and inertial navigation information; and (3) on the basis of time synchronization of range finding values, the ground user estimates the positions of himself / herself in real time in a Kalman filtering positioning algorithm. Thus, interference and cheating sources aimed at the L-frequency-band navigation signals can be avoided, possible problems caused by failure of the L-frequency-band navigation signals are solvedto certain extent, and the navigation safety of a key area in the special scene is ensured.

The invention discloses an indoor robot positioning method based on UWB, and the method comprises the steps: setting a clock reference base station, taking the time of the base station as the standard, and calculating the clock offset of other base stations according to the clock reference base station during each time of time synchronization; and calculating the time offset between the robot andthe base station during positioning on the basis of the clock offset of the base station, and carrying out time correction according to the obtained time offset in the subsequent positioning process between the robot and the base station. The clock model is created for each base station, so that the correction of the local arrival time of the positioning signal is realized, a decentralized calculation method is provided, and the real-time performance of positioning is improved; and meanwhile, the defect of long channel occupation time in local arrival time correction of the TWR method in the prior art is avoided, and a foundation is laid for later expansion performance while the energy consumption is saved.

Methods simulating a system of devices are described. A model that simulates the system is executed. The system model includes a plurality of modules. A clock object for a module can be disabled when it is not needed or not being used.

A method for determining an instantaneous phase difference between time bases of at least two location anchors for a desired point in time (t), each of the location anchors having transmitting and receiving access to a joint broadcast transmission medium and a respective time base for measuring time, wherein a first of the location anchors broadcasts a first broadcast message at least twice; the first location anchor and at least a second of the location anchors receive the first broadcast messages; the second location anchor broadcasting a second broadcast message at least twice; and the second location anchor and at least the first location anchor receive the second broadcast messages. The location server calculates the instantaneous phase difference from a determined first and second clock model functions and from a time elapsed between a reference point in time and the desired point in time t.

The invention discloses a micro-grid distributed secondary control clock synchronization method based on event triggering, and the method comprises the following steps: S1, building a local clock model of a distributed power supply, and introducing frequency and offset correction parameters to correct the clock model; S2, designing event triggering conditions, carrying out judgment at the local sampling moment, and sampling and transmitting local correction parameter information to neighbor nodes only when the triggering conditions are met; S3, based on a pinning consistency theory, optimally selecting a pinning clock and establishing a distributed clock synchronization protocol; and S4, determining a local sampling moment according to the corrected clock, establishing distributed secondary control of the micro-grid, and realizing synchronous information interaction among the distributed power supplies. According to the method, the clock synchronization problem in distributed secondary control is concerned, the local clock model of the distributed power supply is established, synchronous information interaction among the distributed power supplies is realized, better synchronous economy and higher synchronous convergence speed are achieved, and the system stability and convergence precision are effectively improved.

The invention discloses an RRU high-precision clock synchronization method based on Kalman sliding window filtering, and the method comprises the steps: taking a timestamp in a PTP message as an observation value, carrying out the calculation of a clock deviation, a frequency deviation and a frequency change rate, carrying out the compensation of a clock through a calculation value, correcting a clock model, and improving the clock synchronization precision between a master node and a slave node. The invention aims to improve the instantaneous jitter phenomenon of high-precision time synchronization caused by timestamp counting deviation due to clock frequency drift determined by hardware characteristics of an RRU clock crystal oscillator, effectively improve the convergence precision of PTP time synchronization, ensure sustainable stability and peak throughput of RRU service operation, and reduce the base station maintenance cost of an operator.

The invention relates to a clock model implementation method and device, computer equipment and a storage medium. The method comprises the following steps: setting a clock generation component for generating a clock; obtaining a test case; generating a clock generation mode according to the test case, and adding the clock generation mode into a clock generation component to generate a corresponding clock by the clock generation component; and transmitting the clock to the top layer of the verification environment in an interface mode, and performing clock verification with the to-be-verified module by adopting the clock. According to the invention, the clock generation assembly is independent of the top layer of the verification environment; a corresponding clock generation mode is generated according to the test case, and the clock generation assembly calls a clock generation mode by adopting a callback mechanism, generates a corresponding clock, and transmits the clock to the top layer of the verification environment by utilizing an interface to perform clock verification on the to-be-verified module, so that the code maintenance of the top layer of the verification environment is simplified, the clock scene is controllable and more flexible, and the maintenance is clearer.

The invention belongs to the field of signal processing, and provides a self-adaptive clock synchronization method with high robustness for defects of the existing Kalman estimation clock synchronization method. The method provided by the invention comprises the steps that the topology model of a wireless sensor network is established; network nodes are divided into multiple levels; a subsequent clock synchronization method is carried out only between adjacent levels; progressive synchronization ultimately develops into global clock synchronization; a network node clock model and a transport model between nodes are established; an H infinity estimation filter is used to carry out relative clock parameter estimation on the nodes of adjacent levels; clock synchronization of adjacent levels is realized; and global clock synchronization is realized. According to the invention, H infinity estimation has the advantage of high robustness; and an H infinity clock synchronization method does not need the priori information of clock model noise, a transmission delay autocorrelation matrix and the like.

The invention relates to a timestamp-free synchronous clock parameter tracking method based on extended Kalman filtering, and belongs to the technical field of wireless sensor networks. A first-order Gaussian Markov model and a clock model are used as state equations to describe the evolution process of clock skew and clock instantaneous offset. An observation equation formed by a timestamp-free synchronization and clock instantaneous offset observation model is established, and the clock skew and clock instantaneous offset are jointly tracked by using a tracking method based on extended Kalman filtering to realize synchronization between the node to be synchronized and the reference clock node. According to the method, simultaneous tracking of the two time-varying parameters can be completed by following the network data flow, a special synchronization frame is not needed to interact synchronization information, the energy consumption is reduced, and the synchronization precision is improved.

The embodiment of the invention discloses a circuit verification method and device, electronic equipment and a storage medium, relates to the technical field of integrated circuits, and aims to improve the verification efficiency of a circuit. The circuit verification method comprises the steps of obtaining clock distribution information of a to-be-verified circuit; loading a preset clock model, and instantiating the clock model into a clock instance of the to-be-verified circuit according to the clock distribution information; and configuring the clock instance so as to verify the to-be-verified circuit by utilizing a clock signal generated by the clock instance. The method is suitable for verifying the circuit.

Examples disclosed herein relate to methods and apparatuses for observing signals transmitted by one or more transmitters in an asynchronous communication network and applying a time reference to generate a clock model. In one embodiment, parameters representing the clock model may then be forwarded to other mobile devices to assist in positioning operations.

Methods simulating a system of devices are described. A model that simulates the system is executed. The system model includes a plurality of modules. A clock object for a module can be disabled when it is not needed or not being used.

Method, arrangement and system for improving a combined use of a plurality of different satellite navigation systems, in which each of the plurality of different satellite navigation systems includes a constellation of at least one satellite. The method includes broadcasting from each satellite of the constellation of a first satellite navigation system the clock models for all satellites of the constellation of a second satellite navigation system.

The invention relates to a matrix model estimation time synchronization method based on wireless network clustering topology, and belongs to the technical field of wireless sensor network communication. The method comprises the following steps: S1, deploying network nodes, constructing a clustered topological structure, analyzing states of the nodes in different crystal oscillator frequency working modes, and establishing a logic clock model for matrix estimation; S2, according to the clustered topological structure, dividing the sychronization into inter-cluster synchronization and intra-cluster synchronization, selecting a high crystal oscillator frequency mode or a low crystal oscillator frequency mode, and estimating a clock drift relative parameter and a clock offset relative parameter through state functions established by different crystal oscillator frequencies; S3, respectively estimating the clock drift and the clock offset of the high and low crystal oscillator frequency modes by adopting maximum likelihood estimation through the estimated clock drift relative parameter and the estimated clock offset relative parameter, and periodically compensating the clock drift and the clock offset. According to the invention, the communication problem of the network nodes in different crystal oscillator frequency modes is effectively solved, and the network reliability and the synchronization precision are improved.

The invention relates to the technical field of micro-grid operation control, and discloses a micro-grid secondary control clock synchronization method with delay robustness. The method comprises the following steps: establishing a local hardware clock model of each distributed power supply, and introducing a correction coefficient to obtain a corrected logic clock reading; transmitting local information to a neighbor node, when a certain node receives neighbor node information, sampling the local information, estimating the relative frequency of a local clock and a neighbor clock by applying a random approximation method, calculating auxiliary variable information, and on the basis, if the neighbor clock is faster than the local clock or is closer to the same reference node, and when an event triggering condition is met, updating a local clock correction coefficient to realize synchronization with a neighbor clock, and finally, determining a secondary control moment according to the corrected logic clock, and establishing the distributed secondary control, so the control performance is improved, and safe and stable operation of the system is guaranteed.

The invention discloses an RRU high-precision clock synchronization method based on Kalman sliding window filtering. The time stamp in a PTP message is used as an observation value, and clock deviation, frequency deviation and frequency change rate are calculated, and the calculated value is used to compare The clock is compensated, and the clock model is revised to improve the clock synchronization accuracy between the master and slave nodes. The purpose is to improve the time stamp count deviation caused by the clock frequency drift determined by the hardware characteristics of the RRU clock crystal oscillator, resulting in the instantaneous jitter phenomenon of high-precision time synchronization, which can effectively improve the convergence accuracy of PTP time synchronization and ensure the reliability of RRU service operation. Continuous stability and peak throughput reduce operators' base station maintenance costs.