WO2024124755A1

WO2024124755A1 - Synchronization method and apparatus for wireless mesh network, and electronic device

Info

Publication number: WO2024124755A1
Application number: PCT/CN2023/087765
Authority: WO
Inventors: 万国峰; 肖良
Original assignee: 海尔优家智能科技（北京）有限公司; 青岛海尔科技有限公司; 海尔智家股份有限公司
Priority date: 2022-12-14
Filing date: 2023-04-12
Publication date: 2024-06-20
Also published as: CN116321399A

Abstract

The present application relates to the technical field of wireless Mesh networks, and discloses a synchronization method for a wireless Mesh network. The Mesh network comprises a plurality of Mesh network nodes connected to each other, and the synchronization method comprises: obtaining external relative execution time in a Mesh control message received by each Mesh network node; obtaining internal relative execution time stored in the Mesh network node; and when the external relative execution time is less than the internal relative execution time, correcting the internal relative execution time. The present application further discloses a synchronization apparatus for a wireless Mesh network and an electronic device.

Description

Synchronization method and device for wireless mesh network, and electronic device

This application is based on the Chinese patent application with application number 202211607106.9 and application date December 14, 2022, and claims the priority of the Chinese patent application. The entire content of the Chinese patent application is hereby introduced into this application as a reference.

Technical Field

The present application relates to the technical field of wireless mesh networks, for example, to a synchronization method and device, and electronic equipment for wireless mesh networks.

Background technique

Wireless mesh network is a high-capacity, high-bandwidth distributed network. It can be regarded as the integration of wireless local area network (WLAN) and Ad hoc mobile self-organizing network, and it brings out the advantages of both. In a large-capacity Bluetooth Mesh network, due to the large coverage area, a group control command message needs to be relayed by multiple Mesh network nodes before it can reach the farthest node. No matter how the relay strategy of the Mesh network node is optimized, it takes time to receive, process and relay messages. After multiple relays, this time will increase exponentially, resulting in the inability of devices in the Mesh network to receive Mesh control messages in the same time. If the coverage area of the Mesh network is large, it will cause the inconsistency of the device responses of the Mesh network nodes that can be seen by the naked eye. For example, if all the lights are turned on, if the coverage area of the Mesh network is large, it can be clearly seen that the lights are turned on in batches from near to far, rather than at the same time as can be seen by the naked eye.

It is found that the following problems exist in the related technology:

The Bluetooth Mesh network uses absolute time for network synchronization. If the device of the Mesh network node cannot quickly resynchronize the network clock after power failure and power-on again, it is easy to cause the device of the Mesh network node to fail to accurately achieve synchronization operation.

Summary of the invention

In order to provide a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. The summary is not an extensive review, nor is it intended to identify key/critical components or delineate the scope of protection of these embodiments, but rather serves as a prelude to the detailed description that follows.

The embodiments of the present disclosure provide a synchronization method and device, and an electronic device for a wireless mesh network, which use a relative time method to implement synchronization operations of Mesh control messages, thereby improving the accuracy of synchronization operations implemented by devices at Mesh network nodes.

In some embodiments, a synchronization method for a wireless mesh Mesh network is provided, wherein the Mesh network includes a plurality of Mesh network nodes connected to each other; the synchronization method includes: obtaining an external relative execution time in a Mesh control message received by the Mesh network node; obtaining an internal relative execution time saved by the Mesh network node; and when the external relative execution time is less than the internal relative execution time, correcting the internal relative execution time.

In some embodiments, a synchronization device for a wireless mesh network includes a processor and a memory storing program instructions, and the processor is configured to execute the aforementioned synchronization method for a wireless mesh network when executing the program instructions.

In some embodiments, the electronic device includes: an electronic device body; and the aforementioned synchronization device for a wireless mesh network, which is installed in the electronic device body.

The above general description and the following description are exemplary and explanatory only and are not intended to limit the present application.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments are exemplarily described by corresponding drawings, which do not limit the embodiments. Elements with the same reference numerals in the drawings are shown as similar elements, and the drawings do not constitute a scale limitation, and wherein:

FIG1 is a schematic diagram of a flow chart of a synchronization method for a wireless mesh network provided by an embodiment of the present disclosure;

FIG2 is a flow chart of another synchronization method for a wireless mesh network provided by an embodiment of the present disclosure;

FIG3 is a flow chart of another synchronization method for a wireless mesh network provided by an embodiment of the present disclosure;

FIG4 is a flow chart of another synchronization method for a wireless mesh network provided by an embodiment of the present disclosure;

FIG5 is a flow chart of another synchronization method for a wireless mesh network provided by an embodiment of the present disclosure;

FIG6 is a scenario diagram of a synchronization method for a wireless mesh network provided by an embodiment of the present disclosure;

FIG7 is a scenario diagram of another synchronization method for a wireless mesh network provided by an embodiment of the present disclosure;

FIG8 is a schematic diagram of the structure of a synchronization device for a wireless mesh network provided by an embodiment of the present disclosure;

FIG. 9 is a schematic diagram of the structure of an electronic device provided by an embodiment of the present disclosure.

Detailed ways

In order to be able to understand the features and technical contents of the embodiments of the present disclosure in more detail, the implementation of the embodiments of the present disclosure is described in detail below in conjunction with the accompanying drawings. The attached drawings are for reference only and are not used to limit the embodiments of the present disclosure. In the following technical description, for the convenience of explanation, a full understanding of the disclosed embodiments is provided through multiple details. However, one or more embodiments can still be implemented without these details. In other cases, to simplify the drawings, well-known structures and devices can be simplified for display.

The terms "first", "second", etc. in the specification and claims of the embodiments of the present disclosure and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchanged where appropriate, so that the embodiments of the embodiments of the present disclosure described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

Unless otherwise specified, the term "plurality" means two or more than two. In the disclosed embodiment, the character "/" indicates that the objects before and after are in an "or" relationship. For example, A/B means: A or B. The term "and/or" is a description of the association relationship between objects, indicating that three relationships may exist. For example, A and/or B means: A or B, or, the three relationships of A and B. The term "corresponding" may refer to an association relationship or a binding relationship, and the correspondence between A and B means that there is an association relationship or a binding relationship between A and B.

Wireless mesh network is also called "multi-hop network". It is a dynamic and continuously expandable network architecture that realizes transmission between wireless devices. A large number of mesh network nodes (terminal devices of mesh network nodes) in the mesh network can automatically connect to form a mesh structure through wireless. Each mesh network node in the network can only communicate with adjacent mesh network nodes. Therefore, it is a self-organizing and self-managing intelligent network. It can build a flexible network without a backbone network.

In a large-capacity Bluetooth Mesh network, the core idea to solve the problem of consistent response of Mesh network nodes is clock synchronization and delayed execution, that is, the Mesh control message sent is a delayed execution message, and the Mesh control message contains the specific value of the delay time.

At present, the synchronization scheme of Bluetooth Mesh network uses absolute time for synchronization, and the master node needs to periodically send synchronization signals to synchronize the entire Mesh network. Mesh network uses absolute time for synchronization, and the synchronization signal will increase the load of the Mesh network. If the synchronization message and the control message conflict, the possibility of control failure will increase. In addition, after the device of the Mesh network node is powered off and powered on again, the Mesh network node needs to quickly resynchronize the network clock to achieve good synchronization control of the Mesh network.

In the disclosed embodiment, the Mesh network uses relative time to synchronize control messages. The Mesh network control message does not calibrate the absolute time, but contains relative time, with the moment when the Mesh network control message is received as the anchor point. The Mesh network node starts to use the crystal oscillator to time when it receives the Mesh network control message, executes the action when the delay time (relative time) arrives, and continuously monitors the Mesh network control message in the air.

As shown in FIG. 1 , an embodiment of the present disclosure provides a synchronization method for a wireless mesh network, wherein the mesh network includes a plurality of mesh network nodes connected to each other, and the synchronization method includes the following steps:

S101: Obtaining an external relative execution time in a Mesh control message received by a Mesh network node.

When a Mesh network node receives a Mesh control message relayed by a mobile phone or other Mesh network node, it extracts the relative execution time (also called delay time or execution time) in the Mesh control message. The relative execution time in the message is the internal relative execution time; when the Mesh network node receives the Mesh control message relayed by the mobile phone or other Mesh network nodes again, the relative execution time in the Mesh control message is extracted as the external relative execution time.

Optionally, the broadcast data structure of the Mesh control message includes a Mesh protocol structure and a timestamp located after the Mesh protocol structure.

The Mesh protocol structure of the Mesh control message includes the model layer (Model Layer), foundation model layer (Foundation Model Layer), access layer (Access Layer), upper transport layer (Upper Transport Layer), lower transport layer (Lower Transport Layer), network layer (Network Layer), bearer layer (Bearer Layer) and Bluetooth low energy core specification layer (Bluetooth Low Energy Core Specification) which are electrically connected in sequence.

If the relative execution time field of the Mesh control message is set in the Mesh protocol structure (such as the access layer or the bearer layer), the Mesh control message will be encrypted and obfuscated by the Mesh network relay nodes during the relay process. The Mesh network receiving nodes need to decrypt and modify the message layer by layer to obtain the delay time in the Mesh control message and achieve network synchronization. This increases the burden of the Mesh protocol, reduces the relay efficiency, and destroys the architecture of the Mesh protocol.

By improving the broadcast data structure of the Mesh control message, it is split into a Mesh protocol structure and a timestamp after the Mesh protocol structure. In the broadcast data structure of the Mesh control message, since the timestamp is set separately after the Mesh protocol structure, the Mesh network receiving node does not need to decrypt and modify it layer by layer, and can directly and timely obtain the external relative execution time in the timestamp to complete network synchronization, thereby improving the accuracy of the device synchronization operation of the Mesh network node.

Optionally, obtaining the external relative execution time in the Mesh control message received by the Mesh network node includes: identifying the timestamp in the broadcast data structure of the Mesh control message; obtaining the relative execution time in the execution time byte of the timestamp; and using the relative execution time in the execution time byte of the timestamp as the external relative execution time.

The external relative execution time (delay time) in the timestamp is used to update the internal relative execution time saved by the Mesh network node to achieve time synchronization of the Mesh network. In the broadcast data structure of the Mesh control message, since the timestamp is set separately in the Mesh protocol structure, the Mesh network receiving node does not need to decrypt and modify it layer by layer, and can directly and timely obtain the external relative execution time in the timestamp to complete network synchronization, thereby improving the accuracy of the device synchronization operation of the Mesh network node.

S102: Obtain the internal relative execution time saved by the Mesh network node.

In actual applications, the internal relative execution time is stored in the internal variables of the Mesh network node. The Mesh network node continuously updates the relative execution time according to the internal system clock, such as starting the timer and the minimum period interrupt. Each time the interrupt is triggered, the relative execution time stored in the internal variable is subtracted from the interrupt period to obtain the updated relative execution time, which is then updated to the internal variables of the Mesh network node.

S103: When the external relative execution time is less than the internal relative execution time, correct the internal relative execution time.

During the synchronization process of the Mesh network, the main control node of the Mesh network (the initiator of the Mesh network synchronization) sends multiple (e.g., 8) repeated control packets (Mesh control messages) to improve the control success rate of the Mesh network synchronization. The repeated control packets are sent serially, and the interval between each two adjacent repeated control packets is a preset time (e.g., the preset time range is between 20-30ms). Since there is a time gap between the first repeated control packet and the last repeated control packet (e.g., a maximum difference of 210ms), it will cause errors in the control consistency of the devices of the Mesh network nodes.

As shown in Figures 6 and 7 below, the mobile phone (main control node of the Mesh network) sends 8 repeated control packets (Mesh control messages) at preset intervals, where the external relative execution time of the 8 Mesh control messages is 200ms. The relay time inside the Mesh network node is 20ms.

The external relative execution time of the first Mesh control message sent by the mobile phone received by Mesh network node 1 is 200ms, the external relative execution time of the first Mesh control message relayed by Mesh network node 1 received by Mesh network node 2 is 180ms, the external relative execution time of the first Mesh control message relayed by Mesh network node 2 received by Mesh network node 3 is 160ms, the external relative execution time of the first Mesh control message relayed by Mesh network node 3 received by Mesh network node 4 is 140ms, the external relative execution time of the first Mesh control message relayed by Mesh network node 4 received by Mesh network node 5 is 120ms, and the external relative execution time of the first Mesh control message relayed by Mesh network node 5 received by Mesh network node 6 is 100ms.

The external relative execution time in the fourth Mesh control message sent by the mobile phone received by Mesh network node 7 is 200ms, the external relative execution time in the fourth Mesh control message relayed by Mesh network node 7 received by Mesh network node 6 is 180ms, and the external relative execution time in the first Mesh control message relayed by Mesh network node 6 received by Mesh network node 5 is 160ms.

For Mesh network node 7, the external relative execution time received in the fourth Mesh control message is 200ms, but this Mesh control message has been delayed by 60ms (taking the preset duration as 20ms as an example). For Mesh network node 6, it is considered that the received external relative execution time of 100ms is less than the saved internal relative execution time of 160ms, so the saved internal relative execution time is corrected (to 100ms).

Therefore, the mesh network node needs to continuously detect the external relative execution time in the subsequent mesh control message, and correct the internal relative execution time when the external relative execution time is less than the internal relative execution time, thereby improving the consistency of mesh network synchronization.

Optionally, correcting the internal relative execution time includes: obtaining an actual time interval between the external relative execution time and the internal relative execution time; and correcting the internal relative execution time when the actual time interval is less than a time interval threshold.

The value range of the time interval threshold can be [80ms, 100ms], for example, 80ms, 85ms, 90ms, 95ms, 100ms. When the actual time interval between the external relative execution time and the internal relative execution time in the Mesh control message is greater than the time interval threshold, it means that the Mesh control message containing the external relative execution time is very likely to be the previous Mesh control message. Interference messages caused by retransmission of control messages. For example, before sending this Mesh control message, for the Mesh control messages that were retransmitted but not dissipated in other Mesh control messages sent by the mobile phone earlier, although the external relative time in the Mesh control message is much smaller than the internal relative time, it is obvious that the Mesh control message is an interference message. Therefore, by judging the actual time interval between the external relative execution time and the internal relative execution time and the time interval threshold, it is determined whether the received Mesh control message is an interference message, so as to avoid the Mesh network node correcting its saved internal relative execution time according to the interference information, and then when the internal relative execution time arrives, the Mesh network node executes the action, thereby improving the accuracy and consistency of Mesh network synchronization.

Optionally, correcting the internal relative execution time includes calculating the corrected internal relative execution time according to the following formula:
_T21 ＝ _T1 - _T01 - _Ts1

Wherein, T ₂₁ is the corrected internal relative execution time, T ₁ is the external relative execution time, T ₀₁ is the first internal processing time of the Mesh network node, and T _s1 is the first random delay time.

For example, the acquired external relative execution time _T1 is 100ms, the first internal processing time _T01 of the Mesh network node is 20ms, and the first random delay time _Ts1 is 2ms, then the corrected second relative time is _T21 = _T1 - _T01 - _Ts1 =100ms-20ms-2ms=78ms.

The external relative execution time, the first internal processing time and the first random delay time are used to correct the internal relative execution time saved by the Mesh network node, thereby improving the accuracy of the internal relative execution time. The Mesh network node uses the corrected internal relative execution time to perform synchronous update of the Mesh network, thereby improving the consistency of synchronous update of the Mesh network.

By adopting the synchronization method for wireless mesh Mesh network provided by the embodiment of the present disclosure, after obtaining the external relative execution time in the Mesh control message received by the Mesh network node, the external relative execution time is compared with the internal relative execution time saved by the Mesh network node, and when the external relative execution time is less than the internal relative execution time, the internal relative execution time is corrected in time. In this way, the synchronization operation of the Mesh network node is realized by using the relative time method, the Mesh network node uses the internal crystal oscillator for timing, and the device of the Mesh network node does not need to quickly resynchronize the network clock after power failure and power on again, which can improve the accuracy of the synchronization operation of the device of the Mesh network node in the Mesh network.

As shown in FIG. 2 , an embodiment of the present disclosure provides a synchronization method for a wireless mesh network, wherein the mesh network includes a plurality of mesh network nodes connected to each other, and the synchronization method includes the following steps:

S201: Obtaining an external relative execution time in a Mesh control message received by a Mesh network node.

S202: Obtain the internal relative execution time saved by the Mesh network node.

S203: When the external relative execution time is less than the internal relative execution time, correct the internal relative execution time.

S204: When the Mesh network node is a relay node, obtain a second random delay time.

The value range of the second random delay time T _s2 is 1-10 ms, for example, 2 ms, 3 ms, 7 ms, and 10 ms.

S205: After the second random delay time, forward the relay Mesh control message of the Mesh network node to other Mesh network nodes.

Optionally, the corrected relay relative execution time in the relay Mesh control message is calculated according to the following formula:
_T31 = _T1 - _T02 - _Ts1

Wherein, T ₃₁ is the corrected relay relative execution time, T ₁ is the external relative execution time, T ₀₂ is the second internal processing time of the Mesh network node, and T _s1 is the first random delay time.

For example, the acquired external relative execution time _T1 is 100ms, the second internal processing time _T02 of the Mesh network node is 30ms, and the first random delay time _Ts1 is 2ms, then the corrected third relative time is _T31 = _T1 - _T02 - _Ts1 =100ms-30ms-2ms=68ms.

By adding the second random delay time, the relay Mesh control message can be effectively prevented from colliding with other control messages. The external relative execution time, the second internal processing time and the first random delay time are used to correct the relay relative execution time in the Mesh network relay node, thereby improving the accuracy of the relay relative execution time.

After the Mesh network relay node corrects the relay relative execution time in the relay Mesh control message of the Mesh network node, it forwards the modified relay Mesh control message to other Mesh network nodes.

In the embodiment of the present disclosure, when the Mesh network node is a relay node, by adding a second random delay time, it is possible to effectively avoid the relay Mesh control message from colliding with other control messages. At the same time, the relay relative execution time in the relay Mesh control message of the Mesh network node is corrected. The next Mesh network node uses the corrected relay relative execution time (i.e., the external relative execution time in the Mesh control message received by the next Mesh network node) to perform synchronous update of the Mesh network, thereby improving the accuracy and consistency of synchronous update of the Mesh network.

As shown in FIG. 3 , an embodiment of the present disclosure provides a synchronization method for a wireless mesh network, wherein the mesh network includes a plurality of mesh network nodes connected to each other, and the synchronization method includes the following steps:

S301: Obtaining an external relative execution time in a Mesh control message received by a Mesh network node.

S302: Obtain the internal relative execution time saved by the Mesh network node.

S303: When the external relative execution time is less than the internal relative execution time and the actual time interval between the external relative execution time and the internal relative execution time is less than the time interval threshold, correct the internal relative execution time.

S304: When the external relative execution time is less than the internal relative execution time and the actual time interval between the external relative execution time and the internal relative execution time is greater than the time interval threshold, discard the received Mesh control message.

S305: When the external relative execution time is greater than the internal relative execution time, discard the received Mesh control message.

After the mesh network node parses and determines the external relative execution time in the mesh control message, it compares it with the saved internal The relative execution time is compared. If the external relative execution time is less than the internal relative execution time, and the actual time interval between the external relative execution time and the internal relative execution time is less than the time interval threshold, the internal relative execution time is corrected; if the external relative execution time is less than the internal relative execution time, and the actual time interval between the external relative execution time and the internal relative execution time is greater than the time interval threshold, it indicates that the Mesh control message containing the external relative execution time is very likely to be an interference message caused by the retransmission of the previous Mesh control message, and the received Mesh control message is discarded; if the external relative execution time is greater than the internal relative execution time, it indicates that the Mesh control message containing the first relative execution message is interference information caused by retransmission, and the received Mesh control message is discarded. In this way, the Mesh network node is prevented from correcting its stored internal relative execution time according to the interference information. When the internal relative execution time arrives, the Mesh network node executes the action, thereby improving the accuracy and consistency of Mesh network synchronization.

As shown in FIG. 4 , an embodiment of the present disclosure provides a synchronization method for a wireless mesh network, wherein the mesh network includes a plurality of mesh network nodes connected to each other, and the synchronization method includes the following steps:

S401: Obtain a Mesh control message received by a Mesh network node; wherein the broadcast data structure of the Mesh control message includes a Mesh protocol structure and a timestamp after the Mesh protocol structure.

Optionally, the timestamp includes a first preset number of byte length (length) bytes, a second preset number of byte type (AD Type) bytes, and a third preset number of byte execution time (timestamp) bytes.

In actual applications, the format of the timestamp is 4 bytes, the first preset byte number is 1 byte, the second preset byte number is 1 byte, and the third preset byte number is 2 bytes. The format of the 4-byte timestamp can be: length (1 byte) + AD Type (1 byte) + timestamp (2 bytes).

The Bluetooth Mesh protocol is implemented based on Bluetooth Low Energy (BLE) broadcasting. The data broadcast by BLE is composed of one or more AD structures (AD Struct). The Mesh control message can be considered as an independent AD Struct. Due to its complex hierarchical structure, the payload left for the access layer is only 11 bytes at most. When the word count of the access layer payload is 11 bytes, the BLE broadcast data has reached the maximum value (31 bytes) and can no longer accommodate the next AD Struct. Therefore, a 4-byte AD Struct is added to the broadcast data structure of the Mesh control message to represent the timestamp.

The Mesh control message of the custom model (vendor model) can only support up to 7 bytes. Excluding the 3-byte custom opcode (vendor opcode), only 4 bytes of parameter payload are left. After evaluation and analysis, the 4-byte parameter payload can also meet the execution requirements of common Mesh network node devices (such as wall switches, lamps or sensors) after compression. Therefore, it is proved that the broadcast data structure of the Mesh control message (7-byte access layer Mesh protocol structure + 4-byte timestamp) is feasible.

For example, controlling the color change of a light is the most complex light control message, and it relies on the most payloads. However, a 4-byte parameter payload can also meet user needs. The 4-byte parameter payload is as follows: transaction code Tid (1 byte) + brightness Lightness (1 byte) + hue Hue (1 byte) + saturation Saturation (1 byte). Here, the transaction code Tid, that is, transaction id, is used to indicate the uniqueness of the message at the application layer. The three HLS parameters that control color originally require 2 bytes to represent, but the control granularity of 256 can already meet user needs and will not affect the user experience, so it can be represented by 1 byte.

It can be seen that the design of the timestamp format in the embodiment of the present disclosure, without affecting the original implementation function of the Mesh control message, because the timestamp is set separately in the Mesh protocol structure, the Mesh network receiving node does not need to decrypt and modify layer by layer, and can directly and timely obtain the external relative execution time in the timestamp, and then complete network synchronization, thereby improving the accuracy of the device synchronization operation of the Mesh network node.

S402: Determine the external relative execution time in the timestamp.

Optionally, determining the external relative execution time in the timestamp includes: identifying the timestamp in the broadcast data structure of the Mesh control message; obtaining the relative execution time in the execution time byte of the timestamp; and using the relative execution time in the execution time byte of the timestamp as the external relative execution time.

In practical applications, first, determine the total number of bytes of the broadcast data structure of the Mesh control message and the number of bytes of the Mesh protocol structure, and calculate the number of bytes of the timestamp based on the total number of bytes of the broadcast data structure of the Mesh control message and the number of bytes of the Mesh protocol structure; verify the number of bytes of the calculated timestamp and the number of bytes of the pre-stored timestamp; when the number of bytes of the calculated timestamp is consistent with the number of bytes of the pre-stored timestamp, determine the timestamp in the broadcast data structure of the Mesh control message according to the number of bytes of the (calculated/pre-stored) timestamp. Then, obtain the relative execution time (external relative execution time) according to the third preset number of bytes of the relative execution time in the timestamp.

Since the timestamp is set separately in the Mesh protocol structure, the receiving nodes of the Mesh network do not need to decrypt and modify layer by layer. By verifying the number of bytes of the calculated timestamp and the number of bytes of the pre-stored timestamp, the accuracy of the external relative execution time in the obtained timestamp is improved, thereby improving the accuracy of the device synchronization operation of the Mesh network nodes.

S403: Correcting the internal relative execution time stored in the Mesh network node according to the external relative execution time.

Optionally, the internal relative execution time saved by the Mesh network node is corrected according to the external relative execution time, including: when the external relative execution time is less than the internal relative execution time, correcting the internal relative execution time.

After receiving the Mesh control message for the first time and saving the external relative execution time in the Mesh control message, the Mesh network node continuously detects the external relative execution time in subsequent Mesh control messages, and corrects the internal relative execution time when the external relative execution time is less than the internal relative execution time, so as to improve the accuracy and consistency of Mesh network synchronization.

The synchronization method for wireless mesh network provided by the embodiment of the present disclosure is used to improve the broadcast data structure of the Mesh control message, split it into a Mesh protocol structure and a timestamp located after the Mesh protocol structure, and use the time The external relative execution time (delay time) in the timestamp is used to update the internal relative execution time saved by the Mesh network node to achieve time synchronization of the Mesh network. In the broadcast data structure of the Mesh control message, since the timestamp is set separately in the Mesh protocol structure, the Mesh network receiving node does not need to decrypt and modify it layer by layer, and can directly and timely obtain the external relative execution time in the timestamp, and then complete the network synchronization, thereby improving the accuracy of the device synchronization operation of the Mesh network node; at the same time, the relative time method is used to achieve the synchronization operation of the Mesh network node. The Mesh network node uses the internal crystal oscillator for timing. The device of the Mesh network node does not need to quickly resynchronize the network clock after power failure and power on again, which can further improve the accuracy of the device synchronization operation of the Mesh network node in the Mesh network.

As shown in FIG5 , the embodiment of the present disclosure provides a synchronization method for a wireless mesh network, and the synchronization method includes the following steps:

S501: Obtain a Mesh control message received by a Mesh network node; wherein the broadcast data structure of the Mesh control message includes a Mesh protocol structure and a timestamp after the Mesh protocol structure.

S502: Determine the external relative execution time in the timestamp.

S503: Correct the internal relative execution time saved by the Mesh network node according to the external relative execution time.

S504: When the Mesh network node is a relay node, correct the relay relative execution time in the relay Mesh control message of the Mesh network node.

S505: Forward the modified relay Mesh control message to other Mesh network nodes.

In the embodiment of the present disclosure, when the Mesh network node is a relay node, the relay relative execution time in the relay Mesh control message of the Mesh network node is corrected. The next Mesh network node uses the corrected third relative execution time to perform synchronous update of the Mesh network, thereby improving the accuracy and consistency of synchronous update of the Mesh network.

In some embodiments, the synchronization method for a wireless mesh network further includes: updating the internal relative execution time stored by the mesh network node according to the system clock.

The Mesh network node continuously updates the relative execution time according to the internal system clock, such as starting the timer and the minimum period interrupt. Each time the interrupt is triggered, the relative execution time saved in the internal variable is subtracted from the interrupt period to obtain the updated relative execution time, which is then updated to the internal variable of the Mesh network node.

According to the system clock, the internal relative execution time saved by the Mesh network node is updated. When the internal relative execution time is reached, the device of the Mesh network node executes the action to realize the synchronous operation of the Mesh network. By improving the accuracy of the internal relative execution time, the accuracy of the synchronous operation of the devices of the Mesh network nodes in the Mesh network is further improved.

In conjunction with the embodiment of the present disclosure shown in FIG8 , a synchronization device for a wireless mesh network is provided, including a processor (processor) 80 and a memory (memory) 81, and may also include a communication interface (Communication Interface) 82 and bus 83. The processor 80, the communication interface 82, and the memory 81 can communicate with each other through the bus 83. The communication interface 82 can be used for information transmission. The processor 80 can call the logic instructions in the memory 81 to execute the synchronization method for the wireless mesh network of the above embodiment.

In addition, the logic instructions in the above-mentioned memory 81 can be implemented in the form of software functional units and can be stored in a computer-readable storage medium when sold or used as an independent product.

The memory 81 is a computer-readable storage medium that can be used to store software programs and computer executable programs, such as program instructions/modules corresponding to the method in the embodiment of the present disclosure. The processor 80 executes the functional application and data processing by running the program instructions/modules stored in the memory 81, that is, the synchronization method for the wireless mesh network in the above method embodiment is implemented.

The memory 81 may include a program storage area and a data storage area, wherein the program storage area may store an operating system and an application required for at least one function; the data storage area may store data created according to the use of the terminal device, etc. In addition, the memory 81 may include a high-speed random access memory and may also include a non-volatile memory.

By using the synchronization device for wireless mesh Mesh network provided by the embodiment of the present disclosure, after obtaining the external relative execution time in the Mesh control message received by the Mesh network node, the external relative execution time is compared with the internal relative execution time saved by the Mesh network node, and when the external relative execution time is less than the internal relative execution time, the internal relative execution time is corrected in time. In this way, the synchronization operation of the Mesh network node is realized by using the relative time method, the Mesh network node uses the internal crystal oscillator for timing, and the device of the Mesh network node does not need to quickly resynchronize the network clock after power failure and power on again, which can improve the accuracy of the synchronization operation of the device of the Mesh network node in the Mesh network.

As shown in FIG9 , an embodiment of the present disclosure provides an electronic device (e.g., a computer, a server, etc.) 90, including: an electronic device body, and the above-mentioned synchronization device 91 for a wireless mesh Mesh network. The synchronization device 91 for a wireless mesh Mesh network is installed on the electronic device body. The installation relationship described here is not limited to placement inside the product, but also includes installation connections with other components of the product, including but not limited to physical connections, electrical connections, or signal transmission connections. It can be understood by those skilled in the art that the synchronization device 91 for a wireless mesh Mesh network can be adapted to a feasible electronic device body, thereby realizing other feasible embodiments.

The embodiment of the present disclosure provides a computer program. When the computer program is executed by a computer, the computer implements the above-mentioned synchronization method for a wireless mesh network.

An embodiment of the present disclosure provides a computer program product, which includes computer instructions stored on a computer-readable storage medium. When the program instructions are executed by a computer, the computer implements the above-mentioned synchronization method for a wireless mesh network.

The present disclosure provides a computer-readable storage medium storing computer-executable instructions. The machine executable instructions are configured to execute the above-mentioned synchronization method for a wireless mesh network.

The computer-readable storage medium mentioned above may be a transient computer-readable storage medium or a non-transitory computer-readable storage medium.

The technical solution of the embodiment of the present disclosure can be embodied in the form of a software product, which is stored in a storage medium and includes one or more instructions for enabling a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in the embodiment of the present disclosure. The aforementioned storage medium may be a non-transient storage medium, including: a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and other media that can store program codes, or a transient storage medium.

The above description and the accompanying drawings fully illustrate the embodiments of the present disclosure so that those skilled in the art can practice them. Other embodiments may include structural, logical, electrical, process and other changes. The embodiments represent only possible changes. Unless explicitly required, individual components and functions are optional, and the order of operation may vary. The parts and features of some embodiments may be included in or replace the parts and features of other embodiments. The scope of the embodiments of the present disclosure includes the entire scope of the claims, and all available equivalents of the claims. When used in this application, although the terms "first", "second", etc. may be used in this application to describe each element, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, without changing the meaning of the description, the first element may be called the second element, and similarly, the second element may be called the first element, as long as all occurrences of the "first element" are renamed consistently and all occurrences of the "second element" are renamed consistently. The first element and the second element are both elements, but may not be the same element. Moreover, the words used in this application are only used to describe the embodiments and are not used to limit the claims. As used in the description of the embodiments and claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. Similarly, the term "and/or" as used in this application refers to any and all possible combinations of one or more of the associated listed items. In addition, when used in this application, the term "comprise" and its variations "comprises" and/or comprising refer to the presence of stated features, integers, steps, operations, elements, and/or components, but do not exclude one or more other features. The existence or addition of a feature, an entirety, a step, an operation, an element, a component and/or a grouping of these. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method or device comprising the element. In this article, each embodiment may focus on the differences from other embodiments, and the same and similar parts between the embodiments may refer to each other. For the methods, products, etc. disclosed in the embodiments, if they correspond to the method part disclosed in the embodiments, then the relevant parts may refer to the description of the method part.

Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software may depend on the specific application and design constraints of the technical solution. The technicians may use different methods for each specific application to implement the described functions, but such implementations should not be considered to exceed the scope of the embodiments of the present disclosure. The technicians may clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here.

In the embodiments disclosed herein, the disclosed methods and products (including but not limited to devices, equipment, etc.) can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units can be only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between each other shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms. The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to implement this embodiment. In addition, each functional unit in the embodiment of the present disclosure may be integrated in a processing unit, or each unit may exist physically alone, or two or more units may be integrated in one unit.

The flowcharts and block diagrams in the accompanying drawings show the possible architectures, functions, and operations of the systems, methods, and computer program products according to the embodiments of the present disclosure. In this regard, each box in the flowchart or block diagram may represent a module, a program segment, or a portion of a code, and the module, program segment, or a portion of a code contains one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions marked in the boxes may also occur in an order different from that marked in the accompanying drawings. For example, two consecutive boxes may actually be executed substantially in parallel, and they may sometimes be executed in the opposite order, depending on the functions involved. In the descriptions corresponding to the flowcharts and block diagrams in the accompanying drawings, the operations or steps corresponding to different boxes may also occur in an order different from that disclosed in the description, and sometimes there is no specific order between different operations or steps. For example, two consecutive operations or steps may actually occur in an order different from that disclosed in the description. The operations may be performed substantially in parallel, or they may sometimes be performed in reverse order, depending on the functions involved. Each block in the block diagram and/or flow chart, and combinations of blocks in the block diagram and/or flow chart, may be implemented by a dedicated hardware-based system that performs the specified functions or actions, or may be implemented by a combination of dedicated hardware and computer instructions.

Claims

A synchronization method for a wireless mesh network, wherein the mesh network includes a plurality of mesh network nodes connected to each other; the synchronization method includes:

Obtain the external relative execution time in the Mesh control message received by the Mesh network node;

Obtaining the internal relative execution time saved by the Mesh network node;

When the external relative execution time is less than the internal relative execution time, the internal relative execution time is corrected.
The synchronization method according to claim 1, wherein the correcting the internal relative execution time comprises:

Obtaining an actual time interval between the external relative execution time and the internal relative execution time;

When the actual time interval is smaller than the time interval threshold, the internal relative execution time is corrected.
The synchronization method according to claim 1 or 2, wherein the correcting the internal relative execution time comprises:

The corrected internal relative execution time is calculated according to the following formula:
T21 ＝ T1 - T01 - Ts1

Wherein, T 21 is the corrected internal relative execution time, T 1 is the external relative execution time, T 01 is the first internal processing time of the Mesh network node, and T s1 is the first random delay time.
The synchronization method according to any one of claims 1 to 3, further comprising:

When the Mesh network node is a relay node, obtaining a second random delay time;

After the second random delay time, the relay Mesh control message of the Mesh network node is forwarded to other Mesh network nodes.
The synchronization method according to any one of claims 1 to 4, further comprising:

In a case where the external relative execution time is greater than the internal relative execution time, the received Mesh control message is discarded.
The synchronization method according to any one of claims 1 to 5, further comprising:

When the external relative execution time is less than the internal relative execution time and an actual time interval between the external relative execution time and the internal relative execution time is greater than a time interval threshold, the received Mesh control message is discarded.
The synchronization method according to any one of claims 1 to 6, wherein the broadcast data structure of the Mesh control message includes a Mesh protocol structure and a timestamp located after the Mesh protocol structure.
The synchronization method according to claim 7, wherein obtaining the external relative execution time in the Mesh control message received by the Mesh network node comprises:

Identifying a timestamp in a broadcast data structure of the Mesh control message;

Obtaining the relative execution time in the execution time byte of the timestamp;

The relative execution time in the execution time byte of the timestamp is used as the external relative execution time.
A synchronization device for a wireless mesh network includes a processor and a memory storing program instructions, wherein the processor is configured to perform the following steps when executing the program instructions:

Obtain the external relative execution time in the Mesh control message received by the Mesh network node;

Obtaining the internal relative execution time saved by the Mesh network node;

When the external relative execution time is less than the internal relative execution time, the internal relative execution time is corrected.
An electronic device, comprising:

an electronic device body; and,

The synchronization device for a wireless mesh network as described in claim 9 is installed in the electronic device body.
A computer program, when executed by a computer, enables the computer to implement the synchronization method for a wireless mesh network according to any one of claims 1 to 8.
A computer program product, comprising computer instructions stored on a computer-readable storage medium, wherein when the program instructions are executed by a computer, the computer implements the synchronization method for a wireless mesh network as claimed in any one of claims 1 to 8.