CN-122002522-A - Broadcast type efficient clock synchronization method for low-power-consumption underwater acoustic communication network node

CN122002522ACN 122002522 ACN122002522 ACN 122002522ACN-122002522-A

Abstract

The invention discloses a broadcasting type efficient clock synchronization method for low-power-consumption underwater acoustic communication network nodes, which comprises the steps that a shore-based control system sends a clock synchronization instruction to an underwater acoustic communication network, after receiving the clock synchronization instruction, a gateway node performs N+2 times of information interaction with each node to be synchronized through an underwater acoustic communication link, a first round of clock synchronization data packet is broadcasted for the gateway node, N times in the middle are N times of clock synchronization data packets returned to the gateway node by the node to be synchronized, a second round of clock synchronization data packet is broadcasted for the gateway node in the next time division multiplexing period, and each node to be synchronized calculates own clock frequency deviation and fixed deviation according to six receiving and transmitting time stamps obtained after the information interaction, so as to correct own crystal oscillator clock. According to the invention, accurate clock synchronization of N nodes to be synchronized and the gateway node in the underwater acoustic communication network is realized through only N+2 times of information interaction, and flexible configuration between clock synchronization accuracy and node energy consumption can be realized.

Inventors

ZHU CHUANQI
WAN RUI
HAN CHENXI
AN LIANG
FANG SHILIANG

Assignees

东南大学

Dates

Publication Date: 20260508
Application Date: 20260107

Claims (10)

1. A broadcast-type efficient clock synchronization method for a low-power-consumption underwater acoustic communication network node, comprising the steps of: Step S1, a shore-based control system issues a clock synchronization command to a water sound communication network to trigger the whole clock synchronization process; S2, after receiving a clock synchronization instruction, a gateway node in the underwater acoustic communication network performs N+2 times of information interaction with each node to be synchronized based on an underwater acoustic communication link of time division multiplexing, wherein the first time is that the gateway node broadcasts a first round of clock synchronization data packet in own time slot, the middle N times are that N nodes to be synchronized reply the clock synchronization data packet to the gateway node in own time slot, and the last time is that the gateway node broadcasts a second round of clock synchronization data packet in own time slot of the next time division multiplexing period; Step S3, each node to be synchronized calculates self clock frequency deviation and fixed deviation according to six receiving and transmitting time stamps obtained after the information interaction in the step S2, wherein the clock frequency deviation is determined according to the self receiving and transmitting time stamps of the first round clock synchronous data packet and the second round clock synchronous data packet which are obtained from the gateway node, the clock fixed deviation is determined according to the self receiving and transmitting time stamps of the first round clock synchronous data packet and the second round clock synchronous data packet which are obtained from the gateway node and the propagation delay between the gateway node and the gateway node, and the propagation delay is determined according to the clock frequency deviation, the self receiving and transmitting time stamp of the self replying clock synchronous data packet and the receiving and transmitting time stamp of the second round clock synchronous data packet which are obtained from the gateway node; And S4, correcting the crystal oscillator clock of each node to be synchronized according to the clock frequency deviation and the fixed deviation calculated in the step S3, and realizing clock synchronization of the node to be synchronized and the gateway node of the whole network.
2. The broadcast type efficient clock synchronization method for the low-power-consumption underwater acoustic communication network node according to claim 1, wherein in step S1, a shore-based control system issues a clock synchronization command to the underwater acoustic communication network through a satellite communication link to trigger the whole clock synchronization process, a gateway node and a node to be synchronized in the underwater acoustic communication network allocate communication resources according to a time division multiplexing protocol, the communication time is divided into n+1 time slots, the gateway node is located in a first time slot, and the rest of the nodes to be synchronized are sequentially allocated to subsequent time slots according to a node number sequence.
3. The broadcasting type efficient clock synchronization method for a low-power-consumption underwater acoustic communication network node according to claim 1, wherein in step S2, after receiving a clock synchronization instruction, a buoy gateway node equipped with a Beidou communication positioning terminal in an underwater acoustic communication network performs information interaction with each node to be synchronized based on an underwater acoustic communication link, specifically comprising: the gateway node initiates clock synchronization when receiving the clock synchronization instruction, and performs the first information interaction, including that the gateway node updates the current clock synchronization times And recording the current clock synchronization times Synchronous with clock Wherein, before the first time of clock synchronization When the gateway node waits for the own time slot, the gateway node records the system clock time at the moment and takes the system clock time as the packet sending time of the data packet, and broadcasts a first round of clock synchronous data packet to the whole underwater acoustic communication network node based on the underwater acoustic communication link, wherein the content comprises Wherein, the method comprises the steps of, For the gateway node number, Synchronizing the packet sending time of the data packet for the first round of clock of the gateway node; after each node to be synchronized receives the first round clock synchronization data packet of the gateway node, the data packet judgment, reading and replying operation is executed, including that when the first round clock synchronization data packet meets the following conditions In the case, the local receiving time and the gateway node data packet content are recorded: wherein, the method comprises the steps of, Is that The current clock synchronization times of the nodes to be synchronized, Is that The current clock synchronization round of the nodes to be synchronized, Is that When each node waiting to be synchronized waits for own time slot, recording system clock time at the moment and taking the time as packet sending time, replying clock synchronization data packet to the gateway node based on the underwater sound communication link, wherein the content comprises Wherein, the method comprises the steps of, Is that Synchronizing the packet sending time of the data packet by the first round clock of the node to be synchronized; After receiving the clock synchronization data packet replied by the node to be synchronized, the gateway node executes data packet judgment and reading operation, and the data packet judgment and reading operation are carried out when the clock synchronization data packet is satisfied Under the condition, recording the local receiving time and the packet sending time of the node data packet to be synchronized, and updating the self clock synchronization round: wherein, the method comprises the steps of, Received for gateway node The first round of clock of the node to be synchronized synchronizes the time of the data packet; When the gateway node waits for the own time slot of the next time division multiplexing period, the system clock time at the moment is recorded, and a second round of clock synchronous data packet is broadcast to each node to be synchronized based on the underwater sound communication link, wherein the content comprises Wherein, the method comprises the steps of, The second round of clock for the gateway node synchronizes the packet sending time, Synchronizing the receiving and transmitting time of the data packet for the first round of clocks of all the nodes to be synchronized recorded by the gateway node; After each node to be synchronized receives the clock synchronization data packet of the gateway node, the data packet judgment and reading operation are executed, including that when the requirement is met Under the condition, each node to be synchronized records the local receiving time and the second round clock synchronous data packet content of the gateway node Wherein, the method comprises the steps of, Is that The node to be synchronized receives the second round of clock synchronization data packet of the gateway node.
4. A broadcast efficient clock synchronization method for a low power consumption underwater acoustic communication network node according to claim 1, characterized in that, in step S3, Clock frequency deviation of number to-be-synchronized nodes Wherein, the method comprises the steps of, 、 The first round and the second round of clock of the gateway node are respectively used for synchronizing the packet sending time of the data packet, 、 Respectively is The time when the node to be synchronized receives the first round clock synchronization data packet and the second round clock synchronization data packet of the gateway node; Clock fixed deviation of number to-be-synchronized nodes Wherein, the method comprises the steps of, For gateway nodes The propagation delay between the nodes to be synchronized is counted, , Is that The first round of clock of the node to be synchronized synchronizes the packet sending time, Is that The time when the node to be synchronized receives the second round clock synchronization data packet of the gateway node, Received for gateway node The first round of clock of the node to be synchronized is synchronous with the moment of the data packet.
5. A broadcast efficient clock synchronization method for a low power consumption underwater acoustic communication network node according to claim 1, wherein in step S4, each node to be synchronized will be current system time Subtracting the clock fixing deviation calculated in step S3 And obtaining corrected system time and finishing correction of clock fixed deviation.
6. The method for efficient clock synchronization of low power consumption underwater acoustic communication network node according to claim 1, wherein in step S4, the correction of crystal oscillator clock comprises each node to be synchronized calculating clock frequency deviation according to step S3 Updating the current crystal oscillator count value of the crystal oscillator Wherein, the method comprises the steps of, Representation of Number to be synchronized node The crystal oscillator count value after the secondary clock is synchronized, Representation of The node clock to be synchronized is a nominal crystal oscillator count value, Each node to be synchronized counts the stable periodic pulse signals generated by the crystal oscillator, and each time the counted value is equal to the updated crystal oscillator counted value And updating the local system time to finish the correction of clock frequency deviation.
7. A broadcast efficient clock synchronization system for a low power consumption underwater acoustic communication network node for implementing a broadcast efficient clock synchronization method for a low power consumption underwater acoustic communication network node according to any of claims 1-6, characterized in that the system comprises: the synchronous triggering module is used for transmitting a clock synchronous command to the underwater acoustic communication network by the shore-based control system and triggering the whole clock synchronous process; The system comprises an information interaction module, a time division multiplexing-based data transmission module and a time division multiplexing-based data transmission module, wherein the information interaction module is used for carrying out N+2 times of information interaction between a gateway node and each node to be synchronized based on a time division multiplexing-based underwater acoustic communication link after receiving a clock synchronization instruction in an underwater acoustic communication network, wherein the first time is used for broadcasting a first round of clock synchronization data packet for the gateway node in a time slot of the gateway node, the middle N times are used for replying the clock synchronization data packet to the gateway node for N nodes to be synchronized in the time slot of the gateway node, and the last time is used for broadcasting a second round of clock synchronization data packet for the gateway node in the time slot of the gateway node in the next time division multiplexing period; The system comprises a deviation calculation module, a clock fixed deviation calculation module, a transmission time delay calculation module and a synchronization module, wherein the deviation calculation module is used for calculating clock frequency deviation and fixed deviation of each node to be synchronized according to six transmission and reception time stamps obtained after information interaction, the clock frequency deviation is determined according to the transmission and reception time stamps of a first round of clock synchronous data packet and a second round of clock synchronous data packet which are obtained by the node, the clock fixed deviation is determined according to the transmission and reception time stamps of the first round of clock synchronous data packet and the second round of clock synchronous data packet which are obtained by the node, and the propagation time delay between the gateway node and the node is determined according to the clock frequency deviation, the transmission and reception time stamp of a self-recovery clock synchronous data packet and the transmission and reception time stamp of the second round of clock synchronous data packet which are obtained by the node; And the clock correction module is used for correcting the crystal oscillator clock of each node to be synchronized according to the calculated clock frequency deviation and the fixed deviation, so that the clock synchronization of the node to be synchronized and the gateway node of the whole network is realized.
8. A computer system comprising a memory, a processor and a computer program stored on the memory and operable on the processor, wherein the computer program when executed by the processor performs the processing steps of a gateway node or a node to be synchronized in a broadcast efficient clock synchronization method for a low power consumption underwater acoustic communication network node according to any of claims 1-6.
9. A computer readable storage medium storing a computer program, characterized in that the computer program when executed by a processor implements the processing steps of a gateway node or a node to be synchronized in a broadcast efficient clock synchronization method for a low power consumption underwater acoustic communication network node according to any of claims 1-6.
10. A computer program product comprising a computer program, characterized in that the computer program, when executed by a processor, implements the processing steps of a gateway node or a node to be synchronized in a broadcast efficient clock synchronization method for a low power consumption underwater acoustic communication network node according to any of the claims 1-6.

Description

Broadcast type efficient clock synchronization method for low-power-consumption underwater acoustic communication network node Technical Field The invention relates to the technical field of wireless networking and underwater acoustic communication, in particular to a broadcast type efficient clock synchronization method for a low-power-consumption underwater acoustic communication network node, which is suitable for time synchronization and collaborative work between a gateway node and a plurality of low-power-consumption underwater nodes in the underwater acoustic communication network. Background With the continuous development of ocean resource development and ocean informatization technology, the underwater acoustic communication network is widely applied to the fields of underwater environment monitoring, underwater sensor network, underwater mobile platform cooperative operation, underwater positioning and navigation and the like. Because the underwater environment cannot directly receive satellite time service signals, the underwater low-power-consumption node generally performs time synchronization with the gateway node with satellite communication and positioning capability in an underwater acoustic communication mode. However, the underwater acoustic communication channel has the characteristics of large propagation delay, limited bandwidth and the like, so that the clock synchronization process is complex and the synchronization precision is limited. Meanwhile, the underwater low-power consumption node generally adopts a crystal oscillator as a local clock source, unavoidable clock deviation exists, and if effective correction is not carried out, clock error is easy to accumulate along with time. However, the existing underwater acoustic communication network clock synchronization method adopts point-to-point interaction or a multi-round handshake mechanism to realize time alignment among nodes, and the method generally needs frequent information interaction, so that not only is the communication load and synchronization time delay increased, but also the node energy consumption is obviously improved, and the long-term stable operation of the low-power-consumption underwater acoustic communication network is not facilitated. Disclosure of Invention Aiming at the defects of the prior art, the invention aims to provide a broadcast type high-efficiency clock synchronization method for low-power-consumption underwater acoustic communication network nodes, which reduces communication overhead and energy consumption, improves clock synchronization precision and synchronization efficiency of the underwater acoustic communication network, and realizes flexible configuration between the clock synchronization precision and the node energy consumption. In order to achieve the above object, according to a first aspect of the present invention, there is provided a broadcast type efficient clock synchronization method for a low power consumption underwater acoustic communication network node, comprising the steps of: Step S1, a shore-based control system issues a clock synchronization command to a water sound communication network to trigger the whole clock synchronization process; S2, after receiving a clock synchronization instruction, a gateway node in the underwater acoustic communication network performs N+2 times of information interaction with each node to be synchronized based on an underwater acoustic communication link of time division multiplexing, wherein the first time is that the gateway node broadcasts a first round of clock synchronization data packet in own time slot, the middle N times are that N nodes to be synchronized reply the clock synchronization data packet to the gateway node in own time slot, and the last time is that the gateway node broadcasts a second round of clock synchronization data packet in own time slot of the next time division multiplexing period; Step S3, each node to be synchronized calculates self clock frequency deviation and fixed deviation according to six receiving and transmitting time stamps obtained after the information interaction in the step S2, wherein the clock frequency deviation is determined according to the self receiving and transmitting time stamps of the first round clock synchronous data packet and the second round clock synchronous data packet which are obtained from the gateway node, the clock fixed deviation is determined according to the self receiving and transmitting time stamps of the first round clock synchronous data packet and the second round clock synchronous data packet which are obtained from the gateway node and the propagation delay between the gateway node and the gateway node, and the propagation delay is determined according to the clock frequency deviation, the self receiving and transmitting time stamp of the self replying clock synchronous data packet and the receiving and transmitting time stamp of the second round clock sync