CN116963209A - Wireless sensor network mobile terminal network switching method considering time synchronization - Google Patents

Wireless sensor network mobile terminal network switching method considering time synchronization Download PDF

Info

Publication number
CN116963209A
CN116963209A CN202311062512.6A CN202311062512A CN116963209A CN 116963209 A CN116963209 A CN 116963209A CN 202311062512 A CN202311062512 A CN 202311062512A CN 116963209 A CN116963209 A CN 116963209A
Authority
CN
China
Prior art keywords
time synchronization
time
parameters
access node
nodes
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202311062512.6A
Other languages
Chinese (zh)
Inventor
张东磊
陆阳
鞠登峰
白巍
王庆
黎炜
陈巳阳
杨辉
李向月
李超
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Super High Voltage Co Of State Grid Ningxia Electric Power Co ltd
State Grid Smart Grid Research Institute Co ltd
State Grid Corp of China SGCC
State Grid Ningxia Electric Power Co Ltd
Original Assignee
Super High Voltage Co Of State Grid Ningxia Electric Power Co ltd
State Grid Smart Grid Research Institute Co ltd
State Grid Corp of China SGCC
State Grid Ningxia Electric Power Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Super High Voltage Co Of State Grid Ningxia Electric Power Co ltd, State Grid Smart Grid Research Institute Co ltd, State Grid Corp of China SGCC, State Grid Ningxia Electric Power Co Ltd filed Critical Super High Voltage Co Of State Grid Ningxia Electric Power Co ltd
Priority to CN202311062512.6A priority Critical patent/CN116963209A/en
Publication of CN116963209A publication Critical patent/CN116963209A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/0005—Control or signalling for completing the hand-off
    • H04W36/0055—Transmission or use of information for re-establishing the radio link
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/0005—Control or signalling for completing the hand-off
    • H04W36/0083—Determination of parameters used for hand-off, e.g. generation or modification of neighbour cell lists
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W56/00—Synchronisation arrangements
    • H04W56/001—Synchronization between nodes
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W84/00—Network topologies
    • H04W84/18—Self-organising networks, e.g. ad-hoc networks or sensor networks
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
    • Y02D30/00—Reducing energy consumption in communication networks
    • Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks

Abstract

The invention discloses a wireless sensor network mobile terminal network switching method considering time synchronization, which comprises the following steps: acquiring channel parameters and path parameters of a current access node of a mobile terminal and logic time parameters and hardware time parameters of nodes in a wireless sensor network; determining a time synchronization evaluation factor of a current access node based on the channel quality determined by the channel parameters, the network resources used by each path determined by the path parameters, and the time synchronization accuracy determined by the hardware time parameters and the logic time parameters; judging whether a switching condition is met or not according to the relation between the time synchronization evaluation factor and a preset threshold value; and when the switching condition is met, switching according to the relation between the current access node and the time synchronization evaluation factors of other nodes. By implementing the invention, the problem that the time service precision of the network is unstable or reduced due to the change of the communication performance of the network in the operation process of the mobile terminal with sensitive time synchronization precision in the wireless sensor network is solved.

Description

Wireless sensor network mobile terminal network switching method considering time synchronization
Technical Field
The invention relates to the technical field of wireless communication, in particular to a wireless sensor network mobile terminal network switching method considering time synchronization.
Background
In recent years, under the background of national double-carbon strategy, the inversion of supply and demand situations of the power industry, the change of load characteristics and the optimization of a power supply structure multiply the regulation pressure of a power grid. The novel power system is built, so that the requirements of China on the power industry are met. The communication technology of the Internet of things and the modern construction depth of the power industry are fused, and technical possibility is provided for constructing a novel power system. The digital converter station is one of the core links of the novel power system construction, and through the application of the communication technology of the Internet of things, the automatic state sensing, the intelligent data analysis and the active early warning of the equipment of the digital converter station are realized, so that the safety level and the management quality and effect of the equipment are improved.
In the power transformation link, the digital convertor station can realize the functions of 24-hour uninterrupted autonomous patrol, real-time high-definition real-time monitoring, fault accurate positioning and the like in a key area by applying mobile patrol operation equipment based on the Internet of things, such as a patrol unmanned aerial vehicle, wearable patrol equipment and the like. To ensure that the functions are realized in real time and precisely, a transmission network with low time delay, high reliability and high time synchronization precision is also needed.
However, the existing method for switching access points by roaming of mobile inspection equipment mainly realizes the switching of the wireless access points by detecting the wireless coverage intensity, and the method mainly solves the communication performance requirements of mobile inspection operation equipment (such as inspection unmanned aerial vehicle and wearable inspection equipment) involved in the inspection of a transformer substation, but cannot meet the requirements of mobile inspection on high communication performance and high time synchronization precision. Therefore, the wireless access point switching of the time service is related to different network areas, and the wireless access point with higher quality of the time service access service is selected, so that the time synchronization precision is improved, which is a problem to be solved urgently.
Disclosure of Invention
In view of this, the present invention provides a method for switching wireless sensor network mobile terminals in consideration of time synchronization, so as to solve the problem that the current method for switching access points to mobile terminals cannot meet the requirements for high communication performance and high time synchronization accuracy.
In a first aspect, the present invention provides a method for switching a wireless sensor network mobile terminal network in consideration of time synchronization, where the method includes: acquiring channel parameters and path parameters of a current access node of a mobile terminal and logic time parameters and hardware time parameters of nodes in a wireless sensor network; determining a time synchronization evaluation factor of a current access node based on the channel quality determined by the channel parameters, the network resources used by each path determined by the path parameters, and the time synchronization accuracy determined by the hardware time parameters and the logic time parameters; judging whether a switching condition is met or not according to the relation between the time synchronization evaluation factor and a preset threshold value; when the switching condition is met, switching is carried out according to the relation between the time synchronization evaluation factor of the current access node and the time synchronization evaluation factors of other nodes, wherein the current access node and the other nodes are nodes in the wireless sensor network.
In this embodiment, the calculation of the time synchronization evaluation factor is realized by acquiring the channel parameter and the path parameter of the current access node of the mobile terminal and the logic time parameter and the hardware time parameter of the node in the wireless sensor network, and meanwhile, the calculated time distribution evaluation factor is compared with the preset threshold, and when the current access node does not meet the requirement (the preset threshold), the switching of the node is enabled, so that the problem that the network time service precision is unstable or the time service precision is reduced due to the change of the communication performance of the wireless sensor network because the terminal with the time synchronization precision requirement in the wireless sensor network is switched among different network nodes in the mobile operation process is solved. The requirements of mobile operation equipment on communication performance and time service precision are met, and the guarantee capability of the wireless sensor network for high-precision synchronous demand service access is improved.
In an alternative embodiment, the method further comprises: and when the switching condition is not met, continuously acquiring the channel parameter, the path parameter, the hardware time parameter and the logic time parameter of the current access node of the mobile terminal, and determining the time synchronization evaluation factor of the current access node.
In this embodiment, when the switching condition is not satisfied, the parameter of the current access node is continuously monitored and the calculation of the time synchronization evaluation factor is performed, so that the current access node can be found in time when the switching condition is satisfied.
In an alternative embodiment, the channel parameters include channel jitter, channel delay, and channel packet loss rate, and the path parameters include a path bandwidth parameter and a path delay parameter; determining a time synchronization evaluation factor of the current access node based on the channel quality determined by the channel parameters, the network resources used by each path determined by the path parameters, and the time synchronization accuracy determined by the hardware time parameters and the logic time parameters, including: calculating channel quality based on the channel jitter, channel delay and weighting of the channel packet loss rate; performing weighted calculation on the path bandwidth parameter and the path delay parameter, and determining network resources used by each path; determining time synchronization accuracy based on the drift correction parameter determined by the hardware time parameter and the offset correction parameter determined by the logic time parameter; and determining a time synchronization evaluation factor of the current access node based on the channel quality, the network resources used by each path and the time synchronization precision weighting result.
In an alternative embodiment, determining the time synchronization accuracy based on the drift correction parameter determined by the hardware time parameter and the offset correction parameter determined by the logic time parameter includes: respectively carrying out iterative updating on the drift correction parameter and the offset correction parameter according to the hardware time parameter and the logic time parameter sent by the data packet between any two nodes; correcting the node clock according to the drift correction parameter and the offset correction parameter updated each time of iteration; and determining the time synchronization precision according to the iteration result.
In an alternative embodiment, determining whether the switching condition is satisfied according to the relationship between the time synchronization evaluation factor and a preset threshold includes: judging the relation between the time synchronization evaluation factor and a preset threshold value; when the time synchronization evaluation factor is smaller than the preset threshold value, determining that a switching condition is met; and when the time synchronization evaluation factor is larger than or equal to the preset threshold value, determining that the switching condition is not met.
In this embodiment, when the time synchronization evaluation factor is smaller than the preset threshold, the switching condition is determined to be satisfied, so that timely switching can be realized when the time synchronization evaluation factor is smaller, and further the high precision requirement of the mobile terminal on time synchronization is satisfied
In an alternative embodiment, the switching is performed according to the relationship between the time synchronization evaluation factor of the current access node and the time synchronization evaluation factors of other nodes, including: acquiring time synchronization evaluation factors in other nodes; when the time synchronization evaluation factor of any node is larger than the time synchronization evaluation factor of the current access node, switching to the corresponding node for access; and when the time synchronization evaluation factors of other nodes are smaller than the time synchronization evaluation factor of the current access node, continuously acquiring the time synchronization evaluation factors of other nodes.
In an alternative embodiment, before obtaining the time synchronization evaluation factor in the other node, the method further includes: and carrying out channel pre-scanning on the current access node.
In this embodiment, the channel is pre-scanned when the switching condition is satisfied by the pre-scanning mechanism, so that the switching time can be reduced when switching is performed, thereby realizing fast switching.
In a second aspect, the present invention provides a wireless sensor network mobile terminal network switching device considering time synchronization, the device comprising: the parameter acquisition module is used for acquiring channel parameters and path parameters of a current access node of the mobile terminal and logic time parameters and hardware time parameters of nodes in the wireless sensor network in real time; the factor calculation module is used for determining a time synchronization evaluation factor of the current access node based on the channel quality determined by the channel parameters, the network resources used by the paths determined by the path parameters and the time synchronization precision determined by the hardware time parameters and the logic time parameters; the switching judging module is used for judging whether the switching condition is met or not according to the relation between the time synchronization evaluation factor and a preset threshold value; and the switching module is used for switching according to the relation between the time synchronization evaluation factor of the current access node and the time synchronization evaluation factors of other nodes when the nodes are switched, wherein the current access node and the other nodes are nodes in the wireless sensor network.
In an alternative embodiment, the method further comprises: and the monitoring module is used for continuously acquiring the channel parameter, the path parameter, the hardware time parameter and the logic time parameter of the current access node of the mobile terminal when the switching condition is not met, and determining the time synchronization evaluation factor of the current access node.
In an alternative embodiment, the channel parameters include channel jitter, channel delay, and channel packet loss rate, and the path parameters include a path bandwidth parameter and a path delay parameter; the factor calculation module includes: the quality calculation module is used for calculating the channel quality based on the weighting of the channel jitter, the channel delay and the channel packet loss rate; the resource calculation module is used for carrying out weighted calculation on the path bandwidth parameter and the path delay parameter and determining network resources used by each path; the precision calculation module is used for determining time synchronization precision based on the drift correction parameters determined by the hardware time parameters and the offset correction parameters determined by the logic time parameters; and the factor calculating sub-module is used for determining a time synchronization evaluation factor of the current access node based on the channel quality, the network resources used by each path and the time synchronization precision weighting result.
In an alternative embodiment, the precision calculation module is specifically configured to: respectively carrying out iterative updating on the drift correction parameter and the offset correction parameter according to the hardware time parameter and the logic time parameter sent by the data packet between any two nodes; correcting the node clock according to the drift correction parameter and the offset correction parameter updated each time of iteration; and determining the time synchronization precision according to the iteration result.
In an alternative embodiment, the switching determination module is specifically configured to: judging the relation between the time synchronization evaluation factor and a preset threshold value; when the time synchronization evaluation factor is smaller than the preset threshold value, determining that a switching condition is met; and when the time synchronization evaluation factor is larger than or equal to the preset threshold value, determining that the switching condition is not met.
In an alternative embodiment, the switching module is specifically configured to: acquiring time synchronization evaluation factors in other nodes; when the time synchronization evaluation factor of any node is larger than the time synchronization evaluation factor of the current access node, switching to the corresponding node for access; and when the time synchronization evaluation factors of other nodes are smaller than the time synchronization evaluation factor of the current access node, continuously acquiring the time synchronization evaluation factors of other nodes.
In an alternative embodiment, the switching module is further configured to perform channel pre-scanning for the current access node before acquiring the time synchronization evaluation factor in the other node.
In a third aspect, the present invention provides a computer device comprising: the wireless sensor network mobile terminal network switching method comprises the steps of storing a computer instruction in a memory, and executing the computer instruction by the processor, wherein the memory and the processor are in communication connection, and the processor executes the wireless sensor network mobile terminal network switching method taking time synchronization into account according to the first aspect or any corresponding embodiment of the first aspect.
In a fourth aspect, the present invention provides a computer readable storage medium, on which computer instructions are stored, where the computer instructions are configured to cause a computer to perform the method for switching networks of wireless sensor networks mobile terminals taking into account time synchronization according to the first aspect or any one of the embodiments corresponding to the first aspect.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.
Fig. 1 is a flow chart of a method for switching a network of a mobile terminal of a wireless sensor network, which takes time synchronization into account according to an embodiment of the present invention;
fig. 2 is a flowchart of a method for switching networks of a wireless sensor network mobile terminal according to another embodiment of the present invention, in which time synchronization is considered;
fig. 3 is a flowchart of a method for switching networks of a wireless sensor network mobile terminal according to still another embodiment of the present invention, in which time synchronization is considered;
fig. 4 is a flowchart of a method for switching networks of a wireless sensor network mobile terminal according to still another embodiment of the present invention, in which time synchronization is considered;
fig. 5 is a block diagram of a wireless sensor network mobile terminal network switching apparatus that accounts for time synchronization according to an embodiment of the present invention;
fig. 6 is a schematic diagram of a hardware structure of a computer device according to an embodiment of the present invention.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
According to an embodiment of the present invention, there is provided an embodiment of a network switching method of a wireless sensor network mobile terminal that takes time synchronization into account, it should be noted that the steps illustrated in the flowchart of the drawings may be performed in a computer system such as a set of computer executable instructions, and that although a logical order is illustrated in the flowchart, in some cases the steps illustrated or described may be performed in an order different from that herein.
In this embodiment, a method for switching a wireless sensor network mobile terminal network with time synchronization is provided, which can be used for electronic devices, such as a computer, a mobile phone, a tablet computer, etc., fig. 1 is a flowchart of a method for switching a wireless sensor network mobile terminal network with time synchronization according to an embodiment of the present invention, as shown in fig. 1, where the flowchart includes the following steps:
step S101, obtaining channel parameters and path parameters of a current access node of a mobile terminal and logic time parameters and hardware time parameters of nodes in a wireless sensor network. Specifically, in the wireless sensor network, parameters of the wireless node, such as channel parameters and path parameters, change along with time, so that the parameters of the node can be collected in real time or at intervals of preset time, and the calculated time synchronization evaluation factor is ensured to be more accurate. The mobile terminal may be a mobile inspection operation device in a power transformation link of a power system, for example, an inspection unmanned aerial vehicle, a wearable inspection device, and the like. The wireless sensor network may be a power grid wireless network architecture employing software-based definitions.
Step S102, determining a time synchronization evaluation factor of the current access node based on the channel quality determined by the channel parameters, the network resources used by the paths determined by the path parameters, and the time synchronization precision determined by the hardware time parameters and the logic time parameters. Specifically, the time synchronization evaluation factor is mainly determined by three parameters, namely, channel quality, network resources used by each path and time synchronization accuracy. For example, the time synchronization evaluation factor may be calculated by a weighted sum of three parameters. Since the acquired parameter changes with time, the time synchronization evaluation factor calculated therefrom also changes with time.
And step S103, judging whether the switching condition is met or not according to the relation between the time synchronization evaluation factor and a preset threshold value. The preset threshold value can be determined according to actual conditions, for example, different preset threshold values are set for different mobile terminals, so that different requirements of different mobile terminals on communication performance and time service precision are met. Specifically, according to the acquisition frequency of the parameters, after a new time synchronization evaluation factor is obtained by each calculation, the new time synchronization evaluation factor is compared with a preset threshold value, and judgment of node switching is performed. Wherein, in judging, the magnitude relation between the time synchronization evaluation factor and a preset threshold value can be compared; when the time synchronization evaluation factor is smaller than the preset threshold value, determining that a switching condition is met; and when the time synchronization evaluation factor is larger than or equal to the preset threshold value, determining that the switching condition is not met. It should be noted that, in theory, the time synchronization evaluation factor of the current access node is gradually reduced, and the time synchronization evaluation factors of other surrounding nodes gradually rise, so the value of the preset threshold value set may be larger, for example, set to 10.
And step S104, when the switching condition is met, switching is carried out according to the relation between the time synchronization evaluation factor of the current access node and the time synchronization evaluation factors of other nodes, wherein the current access node and the other nodes are nodes in the wireless sensor network. Specifically, when the time synchronization evaluation factor is smaller than a preset threshold, it is determined that the switching condition is satisfied, and switching of the node can be performed. At this time, the time synchronization evaluation factors of other nodes can be calculated in the same way, the calculated time synchronization evaluation factors of the current access node are compared, and if the time synchronization evaluation factor of a certain node is greater than the time synchronization evaluation factor of the current access node, the switching of the nodes is performed.
Specifically, after step S104, further includes:
step S105, when the switching condition is not satisfied, continuously acquiring the channel parameter, the path parameter, the hardware time parameter and the logic time parameter of the current access node of the mobile terminal, and determining the time synchronization evaluation factor of the current access node. Specifically, when the time synchronization evaluation factor is greater than or equal to a preset threshold, judging that the switching condition is not met, and not switching the node. At this time, the parameters of the current access node can be continuously acquired to calculate the time synchronization evaluation factor, and the time synchronization evaluation factor is compared with a preset threshold value.
According to the wireless sensor network mobile terminal network switching method considering time synchronization, the time synchronization evaluation factor is calculated by acquiring the channel parameter and the path parameter of the current access node of the mobile terminal and the logic time parameter and the hardware time parameter of the nodes in the wireless sensor network, meanwhile, the calculated time distribution evaluation factor is compared with the preset threshold, and when the current access node does not meet the requirement (the preset threshold), the nodes can be switched, so that the problem that the network time service precision is unstable or the time service precision is reduced due to the change of the communication performance of the wireless sensor network when the terminal with the time synchronization precision requirement in the wireless sensor network is switched among different network nodes in the mobile operation process is solved. The requirements of mobile operation equipment on communication performance and time service precision are met, and the guarantee capability of the wireless sensor network for high-precision synchronous demand service access is improved.
In this embodiment, a method for switching a network of a wireless sensor network mobile terminal according to time synchronization is provided, and fig. 2 is a flowchart of a method for switching a network of a wireless sensor network mobile terminal according to time synchronization according to an embodiment of the present invention, as shown in fig. 2, where the flowchart includes the following steps:
Step S201, obtaining channel parameters and path parameters of a current access node of a mobile terminal and logic time parameters and hardware time parameters of nodes in a wireless sensor network.
Step S202, determining a time synchronization evaluation factor of the current access node based on the channel quality determined by the channel parameter, the network resource used by the path determined by the path parameter, and the time synchronization accuracy determined by the hardware time parameter and the logic time parameter.
Specifically, the channel parameters include channel jitter, channel delay and channel packet loss rate, and the path parameters include path bandwidth parameters and path delay parameters; the step S202 includes:
step S2021, calculating the channel quality based on the channel jitter, the channel delay and the weighting of the channel packet loss rate; specifically, the channel quality is calculated using the following formula:
wherein k is l ，k j ，k p Are all weight coefficients; r is R l Representing channel jitter; r is R j Channel delay; r is R p Channel packet loss rate.
Step S2022, carrying out weighted calculation on the path bandwidth parameter and the path delay parameter, and determining network resources used by each path; specifically, the network resources used by each path are calculated using the following formula:
Wherein k is B ，k τ Corresponding to bandwidth and delayWeight coefficient, l represents a link on the path; b is the total bandwidth of the path; τ is the total path delay; τ l For delay on each link; b (B) l An occupied bandwidth on each link; h p For the number of hops on each candidate path.
Step S2023, determining time synchronization accuracy based on the drift correction parameter determined by the hardware time parameter and the offset correction parameter determined by the logic time parameter; specifically, the calculated drift correction parameter and offset correction parameter are used to correct the node clock, wherein the process of correction can be determined by an iterative process so that the corrected clock is close to global time, thereby obtaining time synchronization accuracy.
In an alternative embodiment, the step S2023 includes:
and a1, respectively carrying out iterative updating on the drift correction parameter and the offset correction parameter according to the hardware time parameter and the logic time parameter sent by the data packet between any two nodes.
Specifically, when the drift correction parameters are updated, the time drift ratio of two nodes is calculated, and the iterative updating of the time drift ratio is determined by adopting the following formula:
wherein eta j,i An estimator representing the time drift ratio of node j and node i; ρ η Is a low-pass filter coefficient, satisfies 0< η <1；η j,i,old Representing the last iteration value of the time drift ratio estimator of the node j and the node i; τ i (t) represents the hardware time of node i; τ j (t j ) Representing the hardware time, t, of a transmitting node j j Representing an absolute reference time when node j generates the time packet; τ i (t j,i ) The self hardware time recorded when the receiving node i receives the time data packet of the transmitting node j is represented; t is t j,old Time of broadcasting time data packet in period of node j is represented; t is t j,i,old Indicating node i was last weekTime to receive the time data packet from node j. The node i and the node j are any two nodes related to time synchronization in the wireless sensor network.
When the time drift ratio is updated, iterative updating of the drift correction parameters is performed based on the time drift ratio, and the process is expressed by the following formula:
wherein ρ is θ Is a weight coefficient, satisfies 0< θ <1；The last iteration value of the parameter is corrected for node i drift.
Iterative updating of the offset correction parameters is determined using the following formula:
wherein, the liquid crystal display device comprises a liquid crystal display device,the last iteration value of the correction parameter is offset for the node i; ρ μ Is a weight coefficient, satisfies 0< μ <1；L j (t j ) Logic time for transmitting node j; l (L) i (t j,i ) The logical time of the node i itself recorded when it received the time packet sent by node j.
Step a2, correcting the node clock according to the drift correction parameter and the offset correction parameter updated in each iteration; specifically, the correction process of the node clock is determined using the following formula:
wherein L is i (t) represents the logical time of node i at time t; will beBecomes a drift correction parameter of the node i; will beThe offset correction parameter, called node i, V, represents the set of all nodes in the wireless sensor network that are involved in time synchronization.
The above iterative process may be performed infinitely many times, so that the final clock approaches global time, i.e.:
wherein, the liquid crystal display device comprises a liquid crystal display device,representing global time in the network.
And a3, determining time synchronization precision according to the iteration result. Specifically, the time synchronization accuracy can be expressed by the following formula:
wherein ε e Representing the synchronization accuracy, t e Representing the execution ending time of the time synchronization algorithm; epsilon (t) represents a time synchronization error; v represents a set of all nodes in the wireless sensor network that are involved in time synchronization, and N represents the number of nodes in the set.
Step S2024 determines a time synchronization evaluation factor of the current access node based on the channel quality, the network resources used by each path, and the time synchronization accuracy weighting result. Specifically, the time synchronization evaluation factor is calculated using the following formula:
α＝βf com +f link +ε e (9)
Wherein, beta, gamma and delta are weight coefficients.
Step S203, judging whether the switching condition is satisfied according to the relation between the time synchronization evaluation factor and a preset threshold value. Please refer to step S103 in the embodiment shown in fig. 1 in detail, which is not described herein.
And step S204, when the switching condition is met, switching is carried out according to the relation between the time synchronization evaluation factor of the current access node and the time synchronization evaluation factors of other nodes, wherein the current access node and the other nodes are nodes in the wireless sensor network. Please refer to step S104 in the embodiment shown in fig. 1 in detail, which is not described herein.
In this embodiment, a method for switching a network of a wireless sensor network mobile terminal according to time synchronization is provided, and fig. 3 is a flowchart of a method for switching a network of a wireless sensor network mobile terminal according to time synchronization according to an embodiment of the present invention, as shown in fig. 3, the method includes the following steps:
step S301, obtaining channel parameters and path parameters of a current access node of a mobile terminal and logic time parameters and hardware time parameters of nodes in a wireless sensor network; please refer to step S101 in the embodiment shown in fig. 1 in detail, which is not described herein.
Step S302, determining a time synchronization evaluation factor of a current access node based on the channel quality determined by the channel parameters, the network resources used by the paths determined by the path parameters, and the time synchronization accuracy determined by the hardware time parameters and the logic time parameters; please refer to step S102 in the embodiment shown in fig. 1 in detail, which is not described herein.
Step S303, judging whether the switching condition is met according to the relation between the time synchronization evaluation factor and a preset threshold value. Please refer to step S103 in the embodiment shown in fig. 1 in detail, which is not described herein.
And step S304, when the switching condition is met, switching is carried out according to the relation between the time synchronization evaluation factor of the current access node and the time synchronization evaluation factors of other nodes, wherein the current access node and the other nodes are nodes in the wireless sensor network.
Specifically, the step S304 includes:
step S3041, when the switching condition is satisfied, performing channel pre-scanning on the current access node; specifically, when the time synchronization evaluation factor of the current access node is smaller than a preset threshold, the mobile terminal determines that the switching condition is met, and at the moment, the mobile terminal stores various associated information of the current access node channel and performs pre-scanning of the channel. The fast switching of the nodes can be realized when other nodes meeting the conditions are found later through the pre-scanning process of the channel, and the switching time of the nodes in switching is reduced.
Step S3042, obtaining time synchronization evaluation factors in other nodes; specifically, after the switching condition is determined to be met and the pre-scanning is performed, the private network controller can actively acquire the detection request frame messages of other surrounding nodes and send the detection request frame messages to the mobile terminal, the mobile terminal scans the nodes to acquire corresponding parameters, and the corresponding node time synchronization evaluation factors are calculated. The calculation of the time synchronization evaluation factor is the same as the calculation of the time synchronization evaluation factor of the current access node, and will not be described in detail here.
Step S3043, when the time synchronization evaluation factor of any node is larger than the time synchronization evaluation factor of the current access node, switching to the corresponding node for access; specifically, after the mobile terminal calculates the time synchronization evaluation factors of other surrounding nodes, the time synchronization evaluation factors can be ranked or directly compared with the time synchronization evaluation factors of the current access node. And when the time synchronization evaluation factor of one node in other surrounding nodes is larger than the time synchronization evaluation factor of the current access node based on the sequencing result or the comparison result, switching the node, and switching the current access node to the node.
And step S3044, when the time synchronization evaluation factors of other nodes are smaller than the time synchronization evaluation factor of the current access node, continuing to acquire the time synchronization evaluation factors of other nodes. Specifically, when determining that the time synchronization evaluation factors of other surrounding nodes are smaller than the time synchronization evaluation factor of the current access node based on the sorting result or the comparison result, switching the nodes is not performed, monitoring the other surrounding nodes continuously, acquiring parameters of the other nodes, calculating the time synchronization evaluation factors and comparing the time synchronization evaluation factors with the time synchronization evaluation factors of the current access node until a node larger than the time evaluation factors of the current access node is found, and switching the nodes.
As a specific application embodiment of the present invention, as shown in fig. 4, the method for switching the wireless sensor network mobile terminal network taking time synchronization into account is implemented by adopting the following flow:
step 1: the mobile terminal obtains the parameters of the current Access node, calculates the time synchronization evaluation factor α of the current Access node (Access Point, AP), and sets a preset threshold, for example, a preset threshold st=10.
Step 2: comparing the calculated time synchronization evaluation factor with a preset threshold value, and when the time synchronization evaluation factor alpha is smaller than the preset threshold value, confirming that the switching condition is met, and executing the step 3; when alpha is larger than or equal to the switching threshold, the switching condition is not met, each parameter of the current access node is continuously monitored, the change of the alpha value of the time synchronization evaluation factor is continuously calculated, and the time synchronization evaluation factor is compared with the preset threshold.
Step 3: and storing each item of associated information of the current access node channel, and starting to pre-scan the channel.
Step 4: after the pre-scanning is completed, the private network controller actively acquires a Probe Request frame (Probe Request) message of surrounding nodes and sends the Probe Request frame (Probe Request) message to the mobile terminal.
Step 5: according to the continuously monitored surrounding scanned nodes, the mobile terminal calculates a corresponding time synchronization evaluation factor alpha, and dynamically sorts alpha from high to low, for example, the values of four AP nodes scanned at a certain moment are sorted as alpha 3 >α 1 >α 2 >α 4 . Time synchronization evaluation factor alpha when current access node Access to a wireless communication system When less than the maximum alpha value in the scanned node, i.e. when alpha Access to a wireless communication system <α 3 I.e. step 6 is executed, and step 5 is executed in a loop if not.
Step 6: will have the maximum time synchronization evaluation factor alpha 3 Setting the node of the mobile terminal as a target access node, and issuing a command to enable the mobile terminal to execute a switching action to complete time synchronizationFast switching of timing points.
According to the wireless sensor network mobile terminal network switching method considering time synchronization, which is provided by the embodiment of the invention, the time synchronization stability of various mobile patrol equipment such as a patrol unmanned aerial vehicle, a wearable patrol equipment and the like is improved, the speed of selecting an access point with more suitable time synchronization precision and switching of the patrol equipment in a wireless network overlapping coverage area is improved, the time synchronization time giving point which is more suitable for the equipment in a multi-access node coverage network area is selected, the more suitable time synchronization precision is obtained, and the resource utilization efficiency and service reliability are improved. In general, the method not only ensures the communication performance required by the inspection equipment, but also improves the time synchronization precision, and can improve the inspection accuracy. And because the method is based on the existing wireless access network architecture, the technical transition can be smoothly carried out, and the transformation cost can be reduced.
In this embodiment, a device for switching a wireless sensor network mobile terminal network that takes time synchronization into account is further provided, and the device is used to implement the foregoing embodiments and preferred embodiments, and is not described in detail. As used below, the term "module" may be a combination of software and/or hardware that implements a predetermined function. While the means described in the following embodiments are preferably implemented in software, implementation in hardware, or a combination of software and hardware, is also possible and contemplated.
The embodiment provides a wireless sensor network mobile terminal network switching device considering time synchronization, as shown in fig. 5, including:
the parameter obtaining module 501 is configured to obtain, in real time, a channel parameter and a path parameter of a current access node of the mobile terminal, and a logic time parameter and a hardware time parameter of a node in the wireless sensor network;
a factor calculating module 502, configured to determine a time synchronization evaluation factor of the current access node based on the channel quality determined by the channel parameter, the network resource used by the path determined by the path parameter, and the time synchronization accuracy determined by the hardware time parameter and the logic time parameter;
A switching judging module 503, configured to judge whether a switching condition is satisfied according to a relationship between the time synchronization evaluation factor and a preset threshold;
and the switching module 504 is configured to switch according to a relationship between a time synchronization evaluation factor of a current access node and time synchronization evaluation factors of other nodes when switching the nodes, where the current access node and the other nodes are nodes in the wireless sensor network.
In an alternative embodiment, the method further comprises: and the monitoring module is used for continuously acquiring the channel parameter, the path parameter, the hardware time parameter and the logic time parameter of the current access node of the mobile terminal when the switching condition is not met, and determining the time synchronization evaluation factor of the current access node.
In an alternative embodiment, the channel parameters include channel jitter, channel delay, and channel packet loss rate, and the path parameters include a path bandwidth parameter and a path delay parameter; the factor calculation module includes: the quality calculation module is used for calculating the channel quality based on the weighting of the channel jitter, the channel delay and the channel packet loss rate; the resource calculation module is used for carrying out weighted calculation on the path bandwidth parameter and the path delay parameter and determining network resources used by each path; the precision calculation module is used for determining time synchronization precision based on the drift correction parameters determined by the hardware time parameters and the offset correction parameters determined by the logic time parameters; and the factor calculating sub-module is used for determining a time synchronization evaluation factor of the current access node based on the channel quality, the network resources used by each path and the time synchronization precision weighting result.
In an alternative embodiment, the precision calculation module is specifically configured to: respectively carrying out iterative updating on the drift correction parameter and the offset correction parameter according to the hardware time parameter and the logic time parameter sent by the data packet between any two nodes; correcting the node clock according to the drift correction parameter and the offset correction parameter updated each time of iteration; and determining the time synchronization precision according to the iteration result.
In an alternative embodiment, the switching determination module is specifically configured to: judging the relation between the time synchronization evaluation factor and a preset threshold value; when the time synchronization evaluation factor is smaller than the preset threshold value, determining that a switching condition is met; and when the time synchronization evaluation factor is larger than or equal to the preset threshold value, determining that the switching condition is not met.
In an alternative embodiment, the switching module is specifically configured to: acquiring time synchronization evaluation factors in other nodes; when the time synchronization evaluation factor of any node is larger than the time synchronization evaluation factor of the current access node, switching to the corresponding node for access; and when the time synchronization evaluation factors of other nodes are smaller than the time synchronization evaluation factor of the current access node, continuously acquiring the time synchronization evaluation factors of other nodes.
In an alternative embodiment, the switching module is further configured to perform channel pre-scanning for the current access node before acquiring the time synchronization evaluation factor in the other node.
Further functional descriptions of the above respective modules and units are the same as those of the above corresponding embodiments, and are not repeated here.
The embodiment of the invention also provides computer equipment, which is provided with the wireless sensor network mobile terminal network switching device taking time synchronization into account shown in the figure 5.
Referring to fig. 6, fig. 6 is a schematic structural diagram of a computer device according to an alternative embodiment of the present invention, as shown in fig. 6, the computer device includes: one or more processors 10, memory 20, and interfaces for connecting the various components, including high-speed interfaces and low-speed interfaces. The various components are communicatively coupled to each other using different buses and may be mounted on a common motherboard or in other manners as desired. The processor may process instructions executing within the computer device, including instructions stored in or on memory to display graphical information of the GUI on an external input/output device, such as a display device coupled to the interface. In some alternative embodiments, multiple processors and/or multiple buses may be used, if desired, along with multiple memories and multiple memories. Also, multiple computer devices may be connected, each providing a portion of the necessary operations (e.g., as a server array, a set of blade servers, or a multiprocessor system). One processor 10 is illustrated in fig. 6.
The processor 10 may be a central processor, a network processor, or a combination thereof. The processor 10 may further include a hardware chip, among others. The hardware chip may be an application specific integrated circuit, a programmable logic device, or a combination thereof. The programmable logic device may be a complex programmable logic device, a field programmable gate array, a general-purpose array logic, or any combination thereof.
Wherein the memory 20 stores instructions executable by the at least one processor 10 to cause the at least one processor 10 to perform a method for implementing the embodiments described above.
The memory 20 may include a storage program area that may store an operating system, at least one application program required for functions, and a storage data area; the storage data area may store data created from the use of the computer device of the presentation of a sort of applet landing page, and the like. In addition, the memory 20 may include high-speed random access memory, and may also include non-transitory memory, such as at least one magnetic disk storage device, flash memory device, or other non-transitory solid-state storage device. In some alternative embodiments, memory 20 may optionally include memory located remotely from processor 10, which may be connected to the computer device via a network. Examples of such networks include, but are not limited to, the internet, intranets, local area networks, mobile communication networks, and combinations thereof.
Memory 20 may include volatile memory, such as random access memory; the memory may also include non-volatile memory, such as flash memory, hard disk, or solid state disk; the memory 20 may also comprise a combination of the above types of memories.
The computer device also includes a communication interface 30 for the computer device to communicate with other devices or communication networks.
The embodiments of the present invention also provide a computer readable storage medium, and the method according to the embodiments of the present invention described above may be implemented in hardware, firmware, or as a computer code which may be recorded on a storage medium, or as original stored in a remote storage medium or a non-transitory machine readable storage medium downloaded through a network and to be stored in a local storage medium, so that the method described herein may be stored on such software process on a storage medium using a general purpose computer, a special purpose processor, or programmable or special purpose hardware. The storage medium can be a magnetic disk, an optical disk, a read-only memory, a random access memory, a flash memory, a hard disk, a solid state disk or the like; further, the storage medium may also comprise a combination of memories of the kind described above. It will be appreciated that a computer, processor, microprocessor controller or programmable hardware includes a storage element that can store or receive software or computer code that, when accessed and executed by the computer, processor or hardware, implements the methods illustrated by the above embodiments.
Although embodiments of the present invention have been described in connection with the accompanying drawings, various modifications and variations may be made by those skilled in the art without departing from the spirit and scope of the invention, and such modifications and variations fall within the scope of the invention as defined by the appended claims.

Claims (10)

1. The wireless sensor network mobile terminal network switching method considering time synchronization is characterized by comprising the following steps:
acquiring channel parameters and path parameters of a current access node of a mobile terminal and logic time parameters and hardware time parameters of nodes in a wireless sensor network;
determining a time synchronization evaluation factor of a current access node based on the channel quality determined by the channel parameters, the network resources used by each path determined by the path parameters, and the time synchronization accuracy determined by the hardware time parameters and the logic time parameters;
judging whether a switching condition is met or not according to the relation between the time synchronization evaluation factor and a preset threshold value;
when the switching condition is met, switching is carried out according to the relation between the time synchronization evaluation factor of the current access node and the time synchronization evaluation factors of other nodes, wherein the current access node and the other nodes are nodes in the wireless sensor network.
2. The method as recited in claim 1, further comprising:
and when the switching condition is not met, continuously acquiring the channel parameter, the path parameter, the hardware time parameter and the logic time parameter of the current access node of the mobile terminal, and determining the time synchronization evaluation factor of the current access node.
3. The method of claim 1, wherein the channel parameters include channel jitter, channel delay, and channel packet loss rate, and the path parameters include path bandwidth parameters and path delay parameters;
determining a time synchronization evaluation factor of the current access node based on the channel quality determined by the channel parameters, the network resources used by each path determined by the path parameters, and the time synchronization accuracy determined by the hardware time parameters and the logic time parameters, including:
calculating channel quality based on the channel jitter, channel delay and weighting of the channel packet loss rate;
performing weighted calculation on the path bandwidth parameter and the path delay parameter, and determining network resources used by each path;
determining time synchronization accuracy based on the drift correction parameter determined by the hardware time parameter and the offset correction parameter determined by the logic time parameter;
And determining a time synchronization evaluation factor of the current access node based on the channel quality, the network resources used by each path and the time synchronization precision weighting result.
4. A method according to claim 3, wherein determining the time synchronization accuracy based on the drift correction parameter determined by the hardware time parameter and the offset correction parameter determined by the logic time parameter comprises:
respectively carrying out iterative updating on the drift correction parameter and the offset correction parameter according to the hardware time parameter and the logic time parameter sent by the data packet between any two nodes;
correcting the node clock according to the drift correction parameter and the offset correction parameter updated each time of iteration;
and determining the time synchronization precision according to the iteration result.
5. The method of claim 1, wherein determining whether a handover condition is satisfied based on a relationship between the time synchronization evaluation factor and a preset threshold value comprises:
judging the relation between the time synchronization evaluation factor and a preset threshold value;
when the time synchronization evaluation factor is smaller than the preset threshold value, determining that a switching condition is met;
and when the time synchronization evaluation factor is larger than or equal to the preset threshold value, determining that the switching condition is not met.
6. The method of claim 1, wherein switching based on the relationship between the time synchronization evaluation factor of the current access node and the time synchronization evaluation factors of other nodes comprises:
acquiring time synchronization evaluation factors in other nodes;
when the time synchronization evaluation factor of any node is larger than the time synchronization evaluation factor of the current access node, switching to the corresponding node for access;
and when the time synchronization evaluation factors of other nodes are smaller than the time synchronization evaluation factor of the current access node, continuously acquiring the time synchronization evaluation factors of other nodes.
7. The method of claim 6, further comprising, prior to obtaining the time synchronization evaluation factor in the other node:
and carrying out channel pre-scanning on the current access node.
8. A wireless sensor network mobile terminal network switching device taking time synchronization into account, the device comprising:
the parameter acquisition module is used for acquiring channel parameters and path parameters of a current access node of the mobile terminal and logic time parameters and hardware time parameters of nodes in the wireless sensor network in real time;
the factor calculation module is used for determining a time synchronization evaluation factor of the current access node based on the channel quality determined by the channel parameters, the network resources used by the paths determined by the path parameters and the time synchronization precision determined by the hardware time parameters and the logic time parameters;
The switching judging module is used for judging whether the switching condition is met or not according to the relation between the time synchronization evaluation factor and a preset threshold value;
and the switching module is used for switching according to the relation between the time synchronization evaluation factor of the current access node and the time synchronization evaluation factors of other nodes when the nodes are switched, wherein the current access node and the other nodes are nodes in the wireless sensor network.
9. A computer device, comprising:
a memory and a processor, the memory and the processor are in communication connection with each other, the memory stores computer instructions, and the processor executes the computer instructions, thereby executing the wireless sensor network mobile terminal network switching method taking time synchronization into account according to any one of claims 1 to 7.
10. A computer-readable storage medium having stored thereon computer instructions for causing a computer to perform the wireless sensor network mobile terminal network handover method taking into account time synchronization according to any one of claims 1 to 7.
CN202311062512.6A 2023-08-22 2023-08-22 Wireless sensor network mobile terminal network switching method considering time synchronization Pending CN116963209A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202311062512.6A CN116963209A (en) 2023-08-22 2023-08-22 Wireless sensor network mobile terminal network switching method considering time synchronization

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202311062512.6A CN116963209A (en) 2023-08-22 2023-08-22 Wireless sensor network mobile terminal network switching method considering time synchronization

Publications (1)

Publication Number Publication Date
CN116963209A true CN116963209A (en) 2023-10-27

Family

ID=88454751

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202311062512.6A Pending CN116963209A (en) 2023-08-22 2023-08-22 Wireless sensor network mobile terminal network switching method considering time synchronization

Country Status (1)

Country Link
CN (1) CN116963209A (en)

Similar Documents

Publication Publication Date Title
CN110891093B (en) Method and system for selecting edge computing node in delay sensitive network
CN107204894B (en) Method and device for monitoring network service quality
WO2017185664A1 (en) Method for positioning terminal, and network device
CN102497665B (en) Mobile terminal time correction method and apparatus thereof
US9167453B2 (en) Cell and evolved node B station outage restoration tool
CN112469075A (en) Service prediction method and device for energy-saving cell
CN113365305A (en) Network coverage data processing method, device, medium and electronic equipment
CN111885618A (en) Network performance optimization method and device
CN112787878A (en) Network index prediction method and electronic equipment
CN104782171A (en) Channel aware job scheduling
CN112434885A (en) Service prediction method and device for energy-saving cell
CN105429144A (en) Information processing method and information processing device for emergency repairing of distribution network
CN116963209A (en) Wireless sensor network mobile terminal network switching method considering time synchronization
CN110662264A (en) Switching method, system, core network device and computer readable storage medium
CN113393046A (en) Photovoltaic power prediction method and application device thereof
CN111225388B (en) Carrier aggregation cell set optimization method and device
CN113923666A (en) Method and device for identifying over-coverage base station, electronic equipment and storage medium
CN116303124B (en) Data searching method and device, electronic equipment and storage medium
CN116739440B (en) Method and device for evaluating intelligent network, electronic equipment and storage medium
CN113015224B (en) Cell reselection method and device, terminal equipment and storage medium
CN116682191B (en) Subway tunnel inspection configuration method and system
CN116707147B (en) Control method of distributed battery energy storage system and related equipment
WO2022121513A1 (en) Method and apparatus for generating worst value of performance index, and electronic device and storage medium
CN114363952B (en) Mobile communication network resource allocation method, device and readable storage medium
WO2024007720A1 (en) Terminal device switching method, base station, electronic device, and storage medium

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination