An efficient distributed navigation method and system based on underwater acoustic dynamic networking

Abstract

This invention discloses an efficient distributed navigation method and system based on dynamic underwater acoustic networking, comprising: first, an underwater mobile platform dynamically selects four underwater acoustic communication network nodes that need to respond to navigation request commands based on its estimated position and the positions of the underwater acoustic communication network nodes; second, the underwater mobile platform calculates the distance between itself and the underwater acoustic communication network nodes that need to respond, and allocates the navigation request command response time slot order; then, the underwater mobile platform fills in and sends a navigation request command containing the number of the selected response node and the response time slot order through designed fields; finally, the underwater acoustic communication network nodes receive the navigation request command, determine whether a response is needed based on the number data field and the time slot allocation field, and obtain the response time slot order. This invention can realize dynamic networking between the underwater mobile platform and the underwater acoustic communication network nodes, and achieve efficient collaborative navigation of a large-scale underwater acoustic communication network based on the time slot division MAC protocol without affecting navigation performance.

Description

Technical Field

[0001] This invention relates to the field of underwater acoustic navigation, specifically to an efficient distributed navigation method and system based on dynamic underwater acoustic networking, applicable to navigation and positioning of underwater mobile platforms in a large-scale distributed underwater acoustic communication network. Background Technology

[0002] Integrated underwater area sensing, communication, and navigation technologies represent a significant development direction in marine information technology, with underwater mobile platform cooperative navigation based on underwater acoustic communication networks being a crucial component. Since high-precision GPS navigation and positioning systems cannot be deployed underwater, underwater mobile platforms acquire location information through the positions of communication network nodes and the acoustic signal transmission delay between the platform and these nodes. Time-division multiplexing (TDM) and other time-slot-based MAC protocols are commonly used for cooperative navigation in underwater acoustic communication networks due to their robustness. However, limitations imposed by low underwater acoustic communication rates, slow underwater sound wave propagation speeds, and large distances between communication network nodes mean that network navigation signaling typically requires long time slots to achieve collision-free and reliable transmission. This reduces the frequency of navigation result updates for underwater mobile platforms, making it difficult to meet real-time requirements.

[0003] Currently, large-scale underwater acoustic communication networks typically employ Time Division Multiple Access (TDMA) protocols based on clustered topology. This involves pre-dividing all network communication nodes into multiple fixed logical clusters to achieve TDMA access management. However, in underwater mobile platform navigation scenarios, existing technologies suffer from the following drawbacks: First, existing clustering protocols, when setting time slot lengths, usually still rely on the maximum propagation delay across the entire domain or the worst-case channel conditions for cross-cluster communication as design benchmarks. This fails to fundamentally shorten the navigation cycle and limits the improvement of navigation update frequency. Second, traditional clustering has fixed geographical or logical boundaries, lacking spatial flexibility. When an underwater mobile platform is located at the intersection of multiple clusters, the inability to flexibly utilize nodes from different clusters prevents the navigation system from constructing the optimal detection geometry, thereby reducing positioning accuracy in edge areas. Summary of the Invention

[0004] Purpose of the invention: To address the shortcomings of existing technologies, the purpose of this invention is to provide an efficient distributed navigation method and system based on underwater acoustic dynamic networking. This method dynamically reconstructs local navigation sub-networks centered on an underwater mobile platform, reduces network size, and simultaneously compresses the number and length of TDMA time slots, thereby achieving efficient navigation of underwater mobile platforms within a large-scale underwater acoustic communication network.

[0005] Technical Solution: To achieve the above-mentioned objectives, the first aspect of this invention provides an efficient distributed navigation method based on underwater acoustic dynamic networking, comprising the following steps:

[0006] Step S1: The underwater mobile platform dynamically selects four underwater acoustic communication network nodes that need to be replied to based on its estimated position and the position of the underwater acoustic communication network nodes. The four nodes are the four vertices of the quadrilateral unit divided in the underwater acoustic communication network.

[0007] Step S2: The underwater mobile platform calculates the distance between itself and the underwater acoustic communication network nodes that need to be replied to, and allocates the reply time slot order;

[0008] Step S3: The underwater mobile platform fills in and sends a navigation request instruction containing the number of the selected reply node and the reply time slot order; the message data segment of the navigation request instruction identifies the number of the node to be replied to through the number data field, and identifies the reply time slot order through a one-byte time slot allocation field; each bit of the number data field corresponds to a node in the underwater acoustic communication network, and is identified by binary to determine whether it is a node to be replied to;

[0009] Step S4: The underwater acoustic communication network node receives the navigation request instruction, determines whether a reply is needed based on the number data field and the time slot allocation field, and obtains the reply time slot order.

[0010] Preferably, step S1, which dynamically selects four underwater acoustic communication network nodes that need to respond, specifically includes:

[0011] Step S101: The nodes in the underwater acoustic communication network are pre-divided into multiple quadrilateral units according to their geographical distribution. Each quadrilateral unit consists of four nodes. The node positions are preset, as well as the mapping relationship between the row index, column index and node number of the node in the network.

[0012] Step S102: The underwater mobile platform calculates the sum of the Manhattan distances between its estimated position and the four underwater acoustic communication network nodes in each quadrilateral cell, selects the quadrilateral network with the smallest sum of distances, and the four underwater acoustic communication network nodes in the selected quadrilateral cell are the underwater acoustic communication network nodes that need to reply to the navigation request command.

[0013] Step S103: Record the numbers and corresponding location coordinates of the four underwater acoustic communication network nodes that need to respond to navigation request commands.

[0014] Preferably, step S2 specifically includes:

[0015] Step S201: The underwater mobile platform calculates its estimated position. Manhattan distance to the four underwater acoustic communication network nodes in the quadrilateral cell selected in step S1 :

[0016]

[0017] in The coordinates of the four nodes;

[0018] Step S202, Distance Sort by distance from smallest to largest. and position index sequence Rank index sequence This refers to the sequence of response time slots for the four selected underwater acoustic communication network nodes.

[0019] Preferably, step S3 specifically includes:

[0020] Step S301: In the navigation request instruction message data segment, select a byte length of... The memory is used to fill in the number data of the selected reply node. ,in The rounding up symbol, , The number of rows and columns represents the rectangular arrangement of the underwater acoustic communication network; the initial value of the numbering data is 0, and each bit uniquely maps to the number of each underwater acoustic communication network node. The underwater mobile platform sets the numbering data according to the following rules. The value:

[0021]

[0022] in It is the arithmetic left shift sign, and it must satisfy the following conditions: ;

[0023] Step S302: In the navigation request command message data segment, one byte of memory is reserved as a time slot allocation field. The time slot allocation field is divided into four consecutive binary bit pairs, which correspond to the four selected underwater acoustic communication network nodes in order from the least significant bit to the most significant bit. The four underwater acoustic communication network nodes are assigned their global numbers. Sort in ascending order from smallest to largest, and the corresponding distance position index sequence Reorder the nodes in ascending order. And fill the corresponding bit pairs with binary codes 00, 01, 10 or 11 respectively to represent the order of the first to fourth response time slots; let the data Fill in the time slot allocation field, whose initial value is 0, then

[0024]

[0025] Step S303: The underwater mobile platform, according to the TDMA protocol, broadcasts data to the entire network at the beginning of each cycle. and Content navigation request instruction message.

[0026] Preferably, step S4 specifically includes:

[0027] Step S401: The underwater acoustic communication network node receives data from the navigation request message. With its own number , judge data The If the bit is 1, a reply is required; otherwise, no reply is required.

[0028] Step S402: If the underwater acoustic communication network node needs to respond, then parse the message data. The statistics are lower than its own number. The number of corresponding bit 1s To uniquely determine the reply slot index within the TDMA cycle and obtain the reply slot order, let the reply slot order of the underwater acoustic communication network node be... ,but

[0029]

[0030] in It is the arithmetic right shift symbol;

[0031] Step S403: The underwater acoustic communication network nodes that need to respond follow the corresponding time slot sequence. Send navigation request response instructions;

[0032] Step S404: The underwater mobile platform receives the navigation request reply instruction and calculates its own position based on the received reply.

[0033] A second aspect of this invention provides a highly efficient distributed navigation system based on underwater acoustic dynamic networking, used to implement the highly efficient distributed navigation method based on underwater acoustic dynamic networking described in the first aspect. The system includes:

[0034] The response node dynamic selection module is used by the underwater mobile platform to dynamically select four underwater acoustic communication network nodes that need to be responded to based on its estimated position and the positions of the nodes in the underwater acoustic communication network; the four nodes are the four vertices of the quadrilateral unit divided in the underwater acoustic communication network;

[0035] The time slot allocation module is used by the underwater mobile platform to calculate the distance between itself and the underwater acoustic communication network nodes that need to be replied to, and to allocate the reply time slot order.

[0036] The navigation request sending module is used by the underwater mobile platform to fill in and send a navigation request instruction containing the number of the selected reply node and the reply time slot order; the message data segment of the navigation request instruction identifies the number of the node to be replied to through a number data field and identifies the reply time slot order through a one-byte time slot allocation field; each bit of the number data field corresponds to a node in the underwater acoustic communication network, and is identified by binary to determine whether it is a node to be replied to;

[0037] The navigation request processing module is used by underwater acoustic communication network nodes to receive navigation request instructions, determine whether a reply is needed based on the number data field and the time slot allocation field, and obtain the reply time slot order.

[0038] Preferably, the nodes in the underwater acoustic communication network are pre-divided into multiple quadrilateral units according to their geographical distribution, and each quadrilateral unit consists of four nodes; in the dynamic selection module for the response node, the underwater mobile platform calculates the sum of the Manhattan distances between its estimated position and the four nodes in each quadrilateral unit, and selects the four nodes corresponding to the quadrilateral unit with the smallest sum of distances as the nodes to be responded to.

[0039] Preferably, when the underwater mobile platform dynamically selects its position based on its own estimated position, the estimated position is a predicted position estimated based on previous navigation results.

[0040] A third aspect of the present invention provides a computer system, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the computer program is executed by the processor, it implements the steps of the efficient distributed navigation method based on underwater acoustic dynamic networking described in the first aspect.

[0041] A fourth aspect of the present invention provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the efficient distributed navigation method based on underwater acoustic dynamic networking described in the first aspect.

[0042] Beneficial Effects: Compared with existing technologies, this invention has the following advantages: 1. The method of this invention designs a new navigation protocol. The underwater mobile platform dynamically selects four underwater acoustic communication network nodes that need to be responded to based on its estimated position and the positions of the nodes in the underwater acoustic communication network. By dynamically networking, the scale of the navigation and positioning network is reduced, and the number and length of TDMA time slots are reduced simultaneously, thereby improving the update frequency and real-time performance of the navigation and positioning results. 2. In the method of this invention, the nodes in the underwater acoustic communication network are pre-divided into multiple quadrilateral units according to their geographical distribution. The underwater mobile platform calculates the sum of the Manhattan distances between its estimated position and the four nodes in each quadrilateral unit, and selects the four nodes corresponding to the quadrilateral unit with the smallest sum of distances as the nodes to be responded to. This method ensures that the four communication network nodes participating in the positioning are always the closest and geometrically optimal combination within the current sea area by dynamically reconstructing the local navigation sub-network in real time with the underwater mobile platform as the center. 3. In the method of the present invention, by adopting a intensive data field design, the length of the selected communication network node and time slot allocation data field is compressed to a few bytes, which minimizes the length of the navigation request message, effectively reduces communication latency, and thus improves the real-time response efficiency and positioning frequency of the navigation system. Attached Figure Description

[0043] Figure 1 This is a flowchart illustrating an efficient distributed navigation method based on underwater acoustic dynamic networking provided in Example 1.

[0044] Figure 2 This is a schematic diagram showing the location distribution of nodes in an underwater acoustic communication network and the movement trajectory of an underwater mobile platform. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] Example 1

[0047] See Figure 1 This embodiment provides an efficient distributed navigation method based on underwater acoustic dynamic networking, including the following steps:

[0048] Step S1: The underwater mobile platform dynamically selects four underwater acoustic communication network nodes that need to be replied to based on its estimated position and the position of the underwater acoustic communication network nodes; the four nodes are the four vertices of the quadrilateral units divided in the underwater acoustic communication network.

[0049] Specifically, in this embodiment, step S1 includes the following steps:

[0050] Step S101: The nodes in the underwater acoustic communication network are pre-divided into multiple quadrilateral units according to their geographical distribution. Each quadrilateral unit consists of four nodes. The node positions and the mapping relationship between the node's row index, column index, and node number in the network are preset. For example, [the following steps are described]. OK The rectangular arrangement of the underwater acoustic communication network is divided into columns. There are quadrilaterals, among which

[0051]

[0052] Let the horizontal coordinate of each underwater acoustic communication network node be:

[0053]

[0054] in and These are the row and column indices of the underwater acoustic communication network nodes within a rectangular network arrangement, respectively. and Corresponding to the x and y coordinates in the preset ocean reference coordinate system, it is easy to obtain the first... Mapping relationship between quadrilaterals and row and column indices for:

[0055]

[0056] achievable Located at the The horizontal coordinates of the four underwater acoustic communication network nodes of the quadrilateral are:

[0057]

[0058] in For the first The row and column indices of the underwater acoustic communication network nodes in the lower left corner of the quadrilateral, within a rectangular underwater acoustic communication network, can be obtained from the mapping relationship. ,Right now:

[0059]

[0060] in The floor symbol is used for rounding down, and the remainder symbol is used for rounding up. represent Remainder .

[0061] Step S102: The underwater mobile platform calculates the sum of the Manhattan distances between its estimated position and the four underwater acoustic communication network nodes in each quadrilateral cell, selects the quadrilateral network with the smallest sum of distances, and the four underwater acoustic communication network nodes located in the selected quadrilateral cell are the underwater acoustic communication network nodes that need to respond to the navigation request command. Specifically, this includes:

[0062] Let the horizontal coordinates of the underwater mobile platform's position be... Calculate the quadrilateral index of the minimum distance sum:

[0063]

[0064] in Using a first-order universal, we obtain the four selected underwater acoustic communication network nodes.

[0065] Step S103: Record the numbers of the four underwater acoustic communication network nodes that need to respond to navigation request commands. The corresponding coordinates are .

[0066] In practical applications, network nodes in underwater acoustic communication networks can generally be considered fixed. If the position of a buoy-type network node shifts, it can be periodically synchronized to the underwater mobile platform. The mobile platform updates its locally stored coordinates based on the network node position information acquired periodically.

[0067] Step S2: The underwater mobile platform calculates the distance between itself and the underwater acoustic communication network nodes that need to be replied to, and allocates the reply time slot order.

[0068] Specifically, in this embodiment, step S2 includes the following steps:

[0069] Step S201: The underwater mobile platform calculates its own position. Manhattan distance to the four underwater acoustic communication network nodes in the quadrilateral network selected in step S1 :

[0070]

[0071] Step S202, Distance Sort by distance from smallest to largest. and position index sequence Rank index sequence This refers to the sequence of response time slots from the four selected underwater acoustic communication network nodes. .

[0072] Step S3: The underwater mobile platform fills in and sends a navigation request instruction containing the number of the selected reply node and the reply time slot order; the message data segment of the navigation request instruction identifies the number of the node to be replied to through the number data field, and identifies the reply time slot order through a one-byte time slot allocation field; each bit of the number data field corresponds to a node in the underwater acoustic communication network, and is identified by binary to determine whether it is a node to be replied to.

[0073] Specifically, in this embodiment, step S3 includes the following steps:

[0074] Step S301: In the navigation request instruction message data segment, select a byte length of... ( The memory allocated for the rounding up sign is used to fill in the number data of the selected reply node. The initial value of this data is 0. Each bit uniquely maps to the number of each underwater acoustic communication network node. The underwater mobile platform selects four underwater acoustic communication network node numbers. Set the corresponding bit of the underwater acoustic communication network node that needs a reply to 1, that is:

[0075]

[0076] in It is the arithmetic left shift sign, and it must satisfy the following conditions: .

[0077] Step S302: In the navigation request command message data segment, one byte of memory is reserved as a time slot allocation field. This field is divided into four consecutive binary bit pairs, which correspond sequentially to the four selected underwater acoustic communication network nodes in ascending order of the least significant bit. The four underwater acoustic communication network nodes are assigned according to their global number. Sort in ascending order from smallest to largest, and the corresponding distance position index sequence Reorder the nodes in ascending order. And fill the corresponding bit pairs with binary codes 00, 01, 10, or 11 respectively to represent the order of the first to fourth response time slots. Assume the data... If the value is filled into this one-byte field, its initial value is 0.

[0078]

[0079] Step S303: The underwater mobile platform, according to the TDMA protocol, broadcasts data to the entire network at the beginning of each cycle. and Content navigation request instruction message.

[0080] Step S4: The underwater acoustic communication network node receives the navigation request instruction, determines whether a reply is needed based on the number data field and the time slot allocation field, and obtains the reply time slot order.

[0081] Specifically, in this embodiment, step S4 includes the following steps:

[0082] Step S401: The underwater acoustic communication network node receives data from the navigation request message. With its own number , judge data The If the bit is 1, a reply is required; otherwise, no reply is required.

[0083] Step S402: If the underwater acoustic communication network node needs to respond, then parse the message data. The statistics are lower than its own number. The number of corresponding bit 1s To uniquely determine the reply slot index within the TDMA cycle and obtain the reply slot order, let the reply slot order of the underwater acoustic communication network node be... ,but

[0084]

[0085] in This is the arithmetic right shift symbol.

[0086] Step S403: The underwater acoustic communication network nodes that need to respond follow the corresponding time slot sequence. Send a navigation request response command.

[0087] Step S404: The underwater mobile platform receives a navigation request response command and calculates its own position based on the received response. The underwater mobile platform can use existing circular intersection positioning methods based on arrival delay for position calculation. This method, as a well-known technology in the field, typically requires distance information from at least three observation points to achieve spatial positioning. The method of this invention preferably uses four nodes to participate in the positioning task. By increasing the observation dimensions and constructing fault-tolerant calculation redundancy, it significantly improves the system's anti-packet loss capability and calculation robustness in complex underwater acoustic environments. Furthermore, this configuration is highly compatible with the intensive message field designed in this invention, thereby achieving optimal control of communication overhead while ensuring high robustness of navigation and positioning.

[0088] More specifically, in this embodiment, a simulation example is also provided, which is as follows:

[0089] In the simulation example of this invention, the simulation signal parameters are set as follows: The simulated underwater mobile platform is... Figure 2The underwater acoustic communication network area shown consists of 20 underwater acoustic communication network nodes numbered 0-19, arranged in a... The smallest topological unit of a rectangular array arrangement is defined as a rectangular array arrangement. Four underwater acoustic communication network nodes are deployed based on the vertices of a square with side length , and the initial position of the underwater mobile platform is set as follows: The ship moves at a constant speed of 4 knots and a heading angle of 45°; assume the speed of sound in seawater. Given a speed of 1500 m / s, considering the maximum communication delay and the time required for the underwater acoustic communication network nodes to process information, and assuming a TDMA time slot length of 24 s, the cycle for the underwater mobile platform to send navigation request commands is 120 s. Simulations were performed using an underwater acoustic communication network with a fixed topology, and 120 navigation calculation results were obtained for the underwater mobile platform.

[0090] According to step S1, Figure 2 The underwater acoustic communication network shown is in rows. Column number The matrix topology is deployed to construct a structure containing The underwater mobile platform is divided into square navigation subnetworks. Based on its estimated position, the platform calculates the sum of Manhattan distances between itself and the four underwater acoustic communication network nodes in each square network. The square network with the smallest sum of distances is selected, and the four underwater acoustic communication network nodes within that selected square network are the communication network nodes that require a response. Assuming the estimated position error is negligible, the platform is initially positioned... For example, the distance sum for each network is calculated separately, and the results are shown in Table 1:

[0091] Table 1. Distances between the underwater mobile platform at its initial position and each network in the simulation example.

[0092]

[0093] As shown in Table 1, when the underwater mobile platform is located At that time, select the underwater acoustic communication network node numbers 0, 1, 5, and 6 that require a response. There are 5 possible navigation subnetwork scenarios for the underwater mobile platform along this path, as follows:

[0094] Table 2. Node selection in the underwater acoustic communication network of the simulation example.

[0095]

[0096] According to step S2, the underwater mobile platform calculates the distance between itself and the underwater acoustic communication network node that needs to be replied to, with the underwater mobile platform at its initial position. For example, the Manhattan distance between the underwater mobile platform and the four selected underwater acoustic communication network nodes is calculated, and the position index sequence is obtained according to the distance order. The response time slot order is as follows:

[0097] Table 3. Response order of underwater acoustic communication network nodes at the initial position of the underwater mobile platform in the simulation example.

[0098]

[0099] As shown in Table 3, when the underwater mobile platform is located At that time, the response time slot order of the underwater acoustic communication network nodes numbered 0, 1, 5, and 6 is 4, 2, 3, and 1. The underwater mobile platform moves along this path, and according to the underwater acoustic communication network node selection in Table 2, the response time slot order of the underwater acoustic communication network nodes is allocated according to step S2, resulting in the results shown in Table 4:

[0100] Table 4. Node response order allocation in the simulation example underwater acoustic communication network

[0101]

[0102] According to step S3, the underwater mobile platform fills in and sends a navigation request instruction containing the number of the selected response node and the order of the response time slots, with a selected byte length of [missing information]. The memory is used to fill in the number data of the selected reply node. Based on the four node response order allocation scenarios in Table 2, the navigation request command message contains... and The content to be filled in, represented in hexadecimal, is as follows:

[0103] Table 5. Navigation Request Command Message Content in Simulation Examples

[0104]

[0105] According to step S4, the underwater acoustic communication network node receives the navigation request instruction and, based on the navigation request instruction message... and The content determines whether a reply is needed and obtains the reply time slot order. The underwater acoustic communication network nodes send navigation reply messages according to the allocation in Table 4. The underwater mobile platform receives the navigation request reply instruction and calculates its own position based on the received reply.

[0106] This simulation example reconstructs the navigation subnetwork through dynamic networking, achieving dual compression of the number and length of time slots. A comparison of specific parameters with the traditional full-network method is shown in the table below:

[0107] Table 6. Comparison of specific parameters between the traditional full-network method and the method of this invention in simulation examples.

[0108]

[0109] As can be seen from Table 6, the period for sending navigation request messages, i.e. the longest waiting time for obtaining navigation results, has been reduced to 11.9% of the original. The method of the present invention has significantly improved the update frequency and efficiency of obtaining navigation results.

[0110] Example 2

[0111] Based on the same inventive concept, this embodiment provides a highly efficient distributed navigation system based on underwater acoustic dynamic networking, comprising: a response node dynamic selection module, used by an underwater mobile platform to dynamically select four underwater acoustic communication network nodes that need to be responded to based on its estimated position and the positions of the underwater acoustic communication network nodes; wherein the four nodes are the four vertices of a quadrilateral unit divided in the underwater acoustic communication network; a time slot allocation module, used by the underwater mobile platform to calculate the distance between itself and the underwater acoustic communication network nodes that need to be responded to, and allocate the response time slot order; a navigation request sending module, used by the underwater mobile platform to fill in and send a navigation request instruction containing the numbers of the selected response nodes and the response time slot order; the message data segment of the navigation request instruction identifies the number of the node to be responded to through a number data field, and identifies the response time slot order through a one-byte time slot allocation field; each bit of the number data field corresponds to a node in the underwater acoustic communication network, and is identified by binary to determine whether it is a node to be responded to; and a navigation request processing module, used by the underwater acoustic communication network nodes to receive the navigation request instruction, determine whether a response is needed based on the number data field and the time slot allocation field, and obtain the response time slot order.

[0112] In this embodiment, the nodes in the underwater acoustic communication network are pre-divided into multiple quadrilateral units according to their geographical distribution, with each quadrilateral unit consisting of four nodes. In the dynamic selection module for response nodes, the underwater mobile platform calculates the sum of its estimated position and the Manhattan distances between the four nodes in each quadrilateral unit, and selects the four nodes corresponding to the quadrilateral unit with the smallest sum of distances as the nodes to be responded to. When the underwater mobile platform dynamically selects nodes based on its estimated position, the estimated position is a predicted position estimated based on previous navigation results. Detailed implementation processes for each module can be found in the aforementioned method embodiment.

[0113] Example 3

[0114] This embodiment provides a computer system, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the computer program is executed by the processor, it implements the steps of the aforementioned efficient distributed navigation method based on underwater acoustic dynamic networking.

[0115] Example 4

[0116] This embodiment provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the aforementioned efficient distributed navigation method based on underwater acoustic dynamic networking.

[0117] Any aspects of this invention not described in detail are well-known to those skilled in the art.

[0118] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A highly efficient distributed navigation method based on underwater acoustic dynamic networking, characterized in that, Includes the following steps: Step S1: The underwater mobile platform dynamically selects four underwater acoustic communication network nodes that need to be replied to based on its estimated position and the position of the underwater acoustic communication network nodes. The four nodes are the four vertices of the quadrilateral unit divided in the underwater acoustic communication network. Step S2: The underwater mobile platform calculates the distance between itself and the underwater acoustic communication network nodes that need to be replied to, and allocates the reply time slot order; Step S3: The underwater mobile platform fills in and sends a navigation request instruction containing the number of the selected reply node and the reply time slot order; the message data segment of the navigation request instruction identifies the number of the node to be replied to through the number data field, and identifies the reply time slot order through a one-byte time slot allocation field; each bit of the number data field corresponds to a node in the underwater acoustic communication network, and is identified by binary to determine whether it is a node to be replied to; Step S4: The underwater acoustic communication network node receives the navigation request instruction, determines whether a reply is needed based on the number data field and the time slot allocation field, and obtains the reply time slot order.

2. The efficient distributed navigation method based on underwater acoustic dynamic networking according to claim 1, characterized in that, The step S1, which dynamically selects four underwater acoustic communication network nodes that require a response, specifically includes: Step S101: The nodes in the underwater acoustic communication network are pre-divided into multiple quadrilateral units according to their geographical distribution. Each quadrilateral unit consists of four nodes. The node positions are preset, as well as the mapping relationship between the row index, column index and node number of the node in the network. Step S102: The underwater mobile platform calculates the sum of the Manhattan distances between its estimated position and the four underwater acoustic communication network nodes in each quadrilateral cell, selects the quadrilateral network with the smallest sum of distances, and the four underwater acoustic communication network nodes in the selected quadrilateral cell are the underwater acoustic communication network nodes that need to reply to the navigation request command. Step S103: Record the numbers and corresponding location coordinates of the four underwater acoustic communication network nodes that need to respond to navigation request commands.

3. The efficient distributed navigation method based on underwater acoustic dynamic networking according to claim 1, characterized in that, Step S2 specifically includes: Step S201: The underwater mobile platform calculates its estimated position. Manhattan distance to the four underwater acoustic communication network nodes in the quadrilateral cell selected in step S1 : ； in The coordinates of the four nodes; Step S202, Distance Sort by distance from smallest to largest. and position index sequence Rank index sequence This refers to the sequence of response time slots for the four selected underwater acoustic communication network nodes.

4. The efficient distributed navigation method based on underwater acoustic dynamic networking according to claim 1, characterized in that, Step S3 specifically includes: Step S301: In the navigation request instruction message data segment, select a byte length of... The memory is used to fill in the number data of the selected reply node. ,in The rounding up symbol, , The number of rows and columns represents the rectangular arrangement of the underwater acoustic communication network; the initial value of the numbering data is 0, and each bit uniquely maps to the number of each underwater acoustic communication network node. The underwater mobile platform sets the numbering data according to the following rules. The value: ； in It is the arithmetic left shift sign, and it must satisfy the following conditions: ; Step S302: In the navigation request command message data segment, one byte of memory is reserved as a time slot allocation field. The time slot allocation field is divided into four consecutive binary bit pairs, which correspond to the four selected underwater acoustic communication network nodes in order from the least significant bit to the most significant bit. The four underwater acoustic communication network nodes are assigned their global numbers. Sort in ascending order from smallest to largest, and the corresponding distance position index sequence Reorder the nodes in ascending order. And fill the corresponding bit pairs with binary codes 00, 01, 10 or 11 respectively to represent the order of the first to fourth response time slots; let the data Fill in the time slot allocation field, whose initial value is 0, then ； Step S303: The underwater mobile platform, according to the TDMA protocol, broadcasts data to the entire network at the beginning of each cycle. and Content navigation request instruction message.

5. The efficient distributed navigation method based on underwater acoustic dynamic networking according to claim 4, characterized in that, Step S4 specifically includes: Step S401: The underwater acoustic communication network node receives data from the navigation request message. With its own number , judge data The If the bit is 1, a reply is required; otherwise, no reply is required. Step S402: If the underwater acoustic communication network node needs to respond, then parse the message data. The statistics are lower than its own number. The number of corresponding bit 1s To uniquely determine the reply slot index within the TDMA cycle and obtain the reply slot order, let the reply slot order of the underwater acoustic communication network node be... ,but ； in It is the arithmetic right shift symbol; Step S403: The underwater acoustic communication network nodes that need to respond follow the corresponding time slot sequence. Send navigation request response instructions; Step S404: The underwater mobile platform receives the navigation request reply instruction and calculates its own position based on the received reply.

6. A high-efficiency distributed navigation system based on underwater acoustic dynamic networking, used to implement the high-efficiency distributed navigation method based on underwater acoustic dynamic networking according to any one of claims 1-5, characterized in that, The system includes: The response node dynamic selection module is used by the underwater mobile platform to dynamically select four underwater acoustic communication network nodes that need to be responded to based on its estimated position and the positions of the nodes in the underwater acoustic communication network; the four nodes are the four vertices of the quadrilateral unit divided in the underwater acoustic communication network; The time slot allocation module is used by the underwater mobile platform to calculate the distance between itself and the underwater acoustic communication network nodes that need to be replied to, and to allocate the reply time slot order. The navigation request sending module is used by the underwater mobile platform to fill in and send a navigation request instruction containing the number of the selected reply node and the reply time slot order; the message data segment of the navigation request instruction identifies the number of the node to be replied to through a number data field and identifies the reply time slot order through a one-byte time slot allocation field; each bit of the number data field corresponds to a node in the underwater acoustic communication network, and is identified by binary to determine whether it is a node to be replied to; The navigation request processing module is used by underwater acoustic communication network nodes to receive navigation request instructions, determine whether a reply is needed based on the number data field and the time slot allocation field, and obtain the reply time slot order.

7. A high-efficiency distributed navigation system based on underwater acoustic dynamic networking according to claim 6, characterized in that, In the underwater acoustic communication network, nodes are pre-divided into multiple quadrilateral units according to their geographical distribution, and each quadrilateral unit consists of four nodes. In the dynamic selection module for response nodes, the underwater mobile platform calculates the sum of the Manhattan distances between its estimated position and the four nodes in each quadrilateral unit, and selects the four nodes corresponding to the quadrilateral unit with the smallest sum of distances as the nodes to be responded to.

8. A high-efficiency distributed navigation system based on underwater acoustic dynamic networking according to claim 7, characterized in that, When the underwater mobile platform dynamically selects its own estimated position, the estimated position is a predicted position estimated based on previous navigation results.

9. A computer system comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the computer program is executed by the processor, it implements the steps of the efficient distributed navigation method based on underwater acoustic dynamic networking as described in any one of claims 1-5.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the efficient distributed navigation method based on underwater acoustic dynamic networking as described in any one of claims 1-5.

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