An ultra-wideband communication and guidance integrated self-organizing network method adapting to complex and unknown environments

Abstract

The present invention discloses an ultra-wideband integrated communication and navigation self-organizing method that adapts to complex and unknown environments. Several nodes are preset and three are randomly selected as initial base stations. The remaining nodes are organized into an unnetworked node set. The three initial base stations transmit a broadcast signal for networking, causing the unnetworked nodes to enter a listening state. The three initial base stations each select the unnetworked node with the strongest networking signal strength for networking. Weighted position estimates of newly added nodes in the dynamic network obtained after the first round of networking and a dynamic map after the first round of networking are calculated. The validity of each base station in the dynamic map after the first round of networking is checked. The initial base stations and the unnetworked node set are determined and updated based on the total number of valid base stations and the number of valid initial base stations. The next round of networking begins at a preset networking time interval T. The above process is repeated until all unnetworked nodes are networked, resulting in a dynamic map consisting of several preset nodes. This method enables flexible base station deployment to cope with complex and changing unknown environments.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to an ultra-wideband communication and guidance integrated self-organizing network method adapting to complex unknown environments. Background Art

[0002] In recent years, UWB (Ultra-WideBand) systems have been widely used in indoor positioning. However, in complex, unknown environments, UWB systems still face the challenge of building a signal network, namely, ad hoc network design. Ad hoc network design involves designing a communication and navigation-integrated ad hoc network that can autonomously explore, connect, collaborate, and manage network nodes, while simultaneously meeting the requirements of flexible and reliable communication and navigation performance, in response to the changing network node topology and the need for rapid base station calibration and positioning in unknown environments. Summary of the Invention

[0003] In order to solve the network topology changes and base station rapid calibration and positioning needs in complex and unknown environments, the present invention application proposes an ultra-wideband integrated communication and navigation self-organizing network method that adapts to complex and unknown environments, which can realize flexible base station layout and cope with complex and changing unknown environments.

[0004] A method for an ultra-wideband communication and guidance integrated self-organizing network adapting to complex unknown environments comprises the following steps:

[0005] S1. Preset a number of nodes, randomly select three of the nodes as initial base stations and construct a two-dimensional plane coordinate system, obtain the positions of the three initial base stations in the two-dimensional plane coordinate system, and form the remaining nodes from the number of nodes into an unnetworked node set;

[0006] S2. Preset the sliding window L and networking time interval T to start the first round of networking: the three initial base stations send a network broadcast signal. Each node in the set of unnetworked nodes enters the listening state. If it receives the network broadcast signal, it replies with a network confirmation signal. After receiving the network confirmation signal, the three initial base stations select the unnetworked node with the strongest network signal strength to form a network, thus obtaining a dynamic network after the first round of networking.

[0007] S3. Using the DCL algorithm, based on the positions of the three initial base stations in the two-dimensional plane coordinate system and a preset sliding window L, calculate weighted estimated values ​​of the positions of the newly added nodes in the dynamic network after the first round of networking, thereby obtaining a self-built map after the first round of networking;

[0008] S4. Align the self-built map after the first round of networking with the known map using the ICP algorithm, find the point in the known map that best matches the newly added node in the self-built map after the first round of networking, and use the position of the point that best matches the newly added node as the position of the newly added node on the known map, thereby obtaining a dynamic map after the first round of networking; wherein each newly added node in the dynamic map after the first round of networking is a base station;

[0009] S5. Check the validity of each base station in the dynamic map after the first round of networking and count the total number of valid base stations after the first round of networking and the number of valid initial base stations among the valid base stations. Determine and update the initial base stations and the set of unnetworked nodes based on the total number of valid base stations after the first round of networking and the number of valid initial base stations among the valid base stations. Start the next round of networking at a preset networking time interval T. Repeat steps S2 to S4 until each node in the set of unnetworked nodes is networked, thereby obtaining a dynamic map consisting of several preset nodes.

[0010] Preferably, S3 specifically includes the following steps:

[0011] S31. Construct an undirected weighted graph G based on the positions of the three initial base stations in the two-dimensional plane coordinate system and the newly added nodes in the dynamic network after the first round of networking, and calculate multiple ranging values ​​and multiple RSS values ​​of the newly added nodes in the dynamic network after the first round of networking within the sliding window L based on the undirected weighted graph G;

[0012] S32, calculating the ranging value covariance and RSS value covariance of the newly added nodes in the dynamic network after the first round of networking according to the multiple ranging values ​​and multiple RSS values ​​of the newly added nodes in the sliding window L;

[0013] S33, calculating the normalized variance of the newly added nodes using the Z-score method based on the ranging value covariance and RSS value covariance of the newly added nodes in the dynamic network after the first round of networking;

[0014] S34. Preset the positions of the newly added nodes in the dynamic network after the first round of networking, establish an objective function based on the positions of the base stations in the dynamic network after the first round of networking, multiple ranging values ​​of the newly added nodes in the dynamic network after the first round of networking within the sliding window L, the normalized variance of the newly added nodes, and the preset positions of the newly added nodes, solve the objective function, and use the position corresponding to the minimum value of the objective function as a weighted estimated value of the position of the newly added nodes in the dynamic network after the first round of networking;

[0015] S35, the positions of the three initial base stations in the two-dimensional plane coordinate system and the weighted estimated values ​​of the positions of the newly added nodes in the dynamic network after the first round of networking constitute the self-built map after the first round of networking.

[0016] Preferably, the covariance of the ranging value and the covariance of the RSS value of the newly added node in S32 can be specifically expressed as:

[0017]

[0018] Where Var() represents covariance, RSS ij is the signal strength value between the newly added node i and the neighboring base station j, d ij is the distance value between the newly added node i and the neighboring base station j, L represents the sliding window, is the kth ranging value between the newly added node i and the neighboring base station j, is the kth measured RSS value between the newly added node i and the neighboring base station j, k = 1, 2, ..., n(L), and n(L) represents the total number of ranging values ​​or RSS values ​​within the sliding window L.

[0019] Preferably, in S33, the Z-score method is used to calculate the normalized variance of the newly added node. The normalized variance can be specifically expressed as:

[0020] Ω ij =ω1X(Var(RSS ij ))+ω2X(Var(d ij ))

[0021] Where, Ω ij represents the normalized variance between the newly added node i and its neighboring base station j, X(*) represents the normalization function, and ω1 and ω2 are both normalized weight coefficients.

[0022] Preferably, the objective function in S34 can be specifically expressed as:

[0023]

[0024] in,

[0025]

[0026] Among them, f(x i ) represents the objective function, x i represents the weighted estimated value of the position of the newly added node i, x j represents the actual location of neighbor base station j, r ij represents the estimated Euclidean distance between the newly added node i and the neighboring base station j, d ij represents the distance value between the newly added node i and the neighboring base station j, M represents the total number of neighboring base stations of the newly added node i, and A ij is the weight between the newly added node i and the neighboring base station j, and σ represents the weight attenuation factor.

[0027] Preferably, checking the validity of each base station in the dynamic map after the first round of networking and counting the total number of valid base stations after the first round of networking and the number of valid initial base stations among the valid base stations in S5 specifically includes:

[0028] S51, randomly selecting a base station from the dynamic map after the first round of networking, and checking whether the selected base station can communicate within a preset sliding window L;

[0029] S52. If the selected base station can communicate within the preset sliding window L, the selected base station is a valid base station; otherwise, the selected base station is an invalid base station;

[0030] S53. Randomly select another base station from the dynamic map after the first round of networking, until all base stations in the dynamic map after the first round of networking are selected, and repeat steps S51 to S52 to obtain validity check results for all base stations;

[0031] S54. Count the total number of valid base stations after the first round of networking and the number of valid initial base stations among the valid base stations based on the validity check results of all base stations.

[0032] Preferably, in S5, judging and updating the initial base stations and the set of unnetworked nodes according to the total number of valid base stations after the first round of networking and the number of valid initial base stations among the valid base stations specifically includes:

[0033] If the total number of valid base stations in the dynamic map after the first round of networking is ≥ 3 and the number of valid initial base stations among the valid base stations is =3, then there is no need to update the initial base stations. The invalid base stations in the dynamic map after the first round of networking are added to the unnetworked node set.

[0034] Alternatively, if the total number of valid base stations in the dynamic map after the first round of networking is ≥3 and the number of valid initial base stations among the valid base stations is less than 3, the initial base stations need to be updated. Specifically, valid base stations with the same number as invalid initial base stations are selected from the dynamic map after the first round of networking as updated initial base stations, and the invalid base stations in the dynamic map after the first round of networking are added to the unnetworked node set.

[0035] The above-mentioned ultra-wideband communication and guidance integrated self-organizing networking method that adapts to complex unknown environments presets several nodes, arbitrarily selects three of the several nodes as initial base stations and constructs a two-dimensional plane coordinate system, obtains the positions of the three initial base stations in the two-dimensional plane coordinate system, and forms a non-networked node set with the remaining nodes in the several nodes. The sliding window and networking time interval are preset, and the three initial base stations send a broadcast signal for networking. Each node in the non-networked node set enters a monitoring state. If a broadcast signal for networking is received, a confirmation signal for networking is replied. After the three initial base stations receive the confirmation signal for networking, the non-networked node with the largest networking signal strength is selected for networking, and a dynamic network after the first round of networking is obtained. The initial base station's position in a two-dimensional plane coordinate system is used to calculate weighted estimates of the positions of newly added nodes in the dynamic network after the first round of networking, generating a self-built map after the first round of networking. The dynamic map after the first round of networking is then generated using the ICP algorithm based on the self-built map after the first round of networking and the known map. The validity of each base station in the dynamic map after the first round of networking is then checked. The initial base station and the set of unnetworked nodes are determined and updated based on the total number of valid base stations after the first round of networking and the number of valid initial base stations among the valid base stations. The next round of networking begins at a preset networking interval T, and steps S2 through S4 are repeated until every node in the set of unnetworked nodes is networked, thereby generating a dynamic map consisting of several preset nodes. This method can dynamically explore unnetworked nodes and address node failures, enabling flexible base station deployment to cope with complex and changing unknown environments such as underground or battlefields. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a flow chart of an ultra-wideband communication and guidance integrated self-organizing network method adapted to complex unknown environments in one embodiment of the present invention;

[0037] Figure 2 Schematic diagram of nodes to be networked in one embodiment of the present invention;

[0038] Figure 3 This is a dynamic network diagram after the first round of networking in one embodiment of the present invention;

[0039] Figure 4 This is a dynamic network diagram after the second round of networking in one embodiment of the present invention;

[0040] Figure 5 This is a dynamic network diagram after the second round of networking in one embodiment of the present invention. DETAILED DESCRIPTION

[0041] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below with reference to the accompanying drawings.

[0042] See also Figure 1 and Figure 2A method for an ultra-wideband communication and guidance self-organizing network adapting to complex and unknown environments, comprising the following steps:

[0043] S1. Preset a number of nodes, randomly select three of the nodes as initial base stations and construct a two-dimensional plane coordinate system, obtain the positions of the three initial base stations in the two-dimensional plane coordinate system, and form the remaining nodes of the number of nodes into an unnetworked node set.

[0044] Specifically, see Figure 2 , Figure 2 In the example, O1, O2, and O3 are three randomly selected nodes. These three nodes are used as the initial base stations. A two-dimensional coordinate system is constructed with initial base station O1 as the origin, the direction from O1 to O2 as the X-axis, and the direction perpendicular to O1 and O2 as the Y-axis. The positions of the three initial base stations in the two-dimensional coordinate system are obtained. According to the principle of three-point positioning, the distance and position information of any node can be determined with the three initial base stations at known locations. The remaining nodes are grouped into a non-networked node set, and their flag bits are set to 0, indicating that they are not networked.

[0045] S2. Preset the sliding window L and networking time interval T to start the first round of networking: the three initial base stations send a networking broadcast signal, and each node in the non-networked node set enters the listening state. If it receives the networking broadcast signal, it replies with a networking confirmation signal. After the three initial base stations receive the networking confirmation signal, they select the non-networked node with the largest networking signal strength for networking, obtaining a dynamic network after the first round of networking.

[0046] Specifically, a sliding window L and a networking time interval T are preset. During the first round of networking, the three initial base stations O1, O2, and O3 send networking broadcast signals in sequence. The nodes in the non-networked node set enter the listening state. If the networking broadcast signal is received, the nodes reply with a networking confirmation signal. Since each initial base station may receive multiple networking confirmation signals, the communication addresses of the non-networked nodes corresponding to each initial base station are recorded at this time. The non-networked nodes corresponding to each initial base station are sorted from large to small according to the networking signal strength. The non-networked nodes corresponding to the largest networking signal strength are selected for networking to obtain the dynamic network after the first round of networking. At this time, there are 3 base stations in the dynamic network after the first round of networking, and 3 new nodes are added. The flag bits of these 3 networked nodes are set to 1 according to the communication address. The three newly added nodes in the dynamic network after the first round of networking are specifically: Figure 2 The nodes are directly connected to the three base stations through solid double arrows. The double arrows indicate that the nodes can communicate in both directions.

[0047] S3. Use the DCL (Distributed Cooperative Localization) algorithm to calculate the weighted estimated position of the newly added nodes in the dynamic network after the first round of networking based on the positions of the three initial base stations in the two-dimensional plane coordinate system and the preset sliding window L, thereby obtaining a self-built map after the first round of networking.

[0048] Furthermore, S3 specifically includes the following steps:

[0049] S31. Construct an undirected weighted graph G based on the positions of the three initial base stations in the two-dimensional plane coordinate system and the newly added nodes in the dynamic network after the first round of networking, and calculate multiple ranging values ​​and multiple RSS values ​​of the newly added nodes in the dynamic network after the first round of networking within the sliding window L based on the undirected weighted graph G.

[0050] Take the dynamic network obtained after the first round of networking as an example. The dynamic network obtained after the first round of networking includes 3 base stations and 3 newly added nodes, which can be represented by an undirected weighted graph G = (ν, ε), where ν = {1, 2, L, 6} represents the set of all base stations and newly added nodes in the dynamic network. For any newly added node i∈ν, the set of its neighbor nodes is defined as: N i ={j∈ν:(i,j)∈ε}, where neighbor nodes are neighboring base stations in the undirected weighted graph G that can directly communicate and measure distance with the newly added node i. The connection between each newly added node i and its neighboring base station j can be considered an edge (i,j), indicating that the newly added node i and its neighboring base station j can directly communicate and measure distance. (i,j)∈ε, where ε represents the set of edges in the undirected weighted graph G. After the first round of networking, all three base stations are neighboring base stations for each newly added node. Multiple ranging values ​​for each newly added node within a preset sliding window can be measured based on the location of each newly added node's neighboring base stations (that is, the location of the neighboring base stations in a two-dimensional plane coordinate system). Multiple RSS (Received Signal Strength) values ​​for each newly added node within a preset sliding window can also be measured based on the communication strength between each newly added node and its neighboring base stations.

[0051] S32. Calculate the ranging value covariance and RSS value covariance of the newly added nodes in the dynamic network after the first round of networking according to the multiple ranging values ​​and multiple RSS values ​​of the newly added nodes in the sliding window L.

[0052] Furthermore, the covariance of the ranging value and the covariance of the RSS value of the newly added node in S32 can be specifically expressed as:

[0053]

[0054] Where Var() represents covariance, RSS ij is the signal strength value between the newly added node i and the neighboring base station j, d ij is the distance value between the newly added node i and the neighboring base station j, L represents the sliding window, is the kth ranging value between the newly added node i and the neighboring base station j, is the kth measured RSS value between the newly added node i and the neighboring base station j, k = 1, 2, ..., n(L), and n(L) represents the total number of ranging values ​​or RSS values ​​within the sliding window L.

[0055] Specifically, the greater the distance between a newly added node and its neighboring base stations, the less impact it has on the estimated location of the newly added node. A stronger signal strength from a neighboring base station has a greater impact on the estimated location of the newly added node. A smaller covariance between the RSS value and the ranging value indicates more stable signal propagation and higher positioning accuracy.

[0056] S33. Calculate the normalized variance of the newly added nodes using the Z-score method based on the ranging value covariance and RSS value covariance of the newly added nodes in the dynamic network after the first round of networking.

[0057] Furthermore, in order to solve the problem that the difference in numerical value and dimension between RSS value and ranging value affects the positioning accuracy, the Z-score method is used to obtain the normalized variance of RSS value and ranging value after metric convergence. The normalized variance of the newly added node in S33 can be specifically expressed as:

[0058] Ω ij =ω1X(Var(RSS ij ))+ω2X(Var(d ij )) (3)

[0059] Where, Ω ij represents the normalized variance between the newly added node i and its neighboring base station j, X(*) represents the normalization function, ω1 and ω2 are both normalized weight coefficients, which can be set according to the fluctuation of the RSS value and the ranging value. The greater the fluctuation, the smaller the normalized weight coefficient. It is used to balance the effects of the RSS value and the ranging value on the position estimation of the newly added node i.

[0060] S34. Preset the position of the newly added node in the dynamic network after the first round of networking, establish an objective function based on the position of the base station in the dynamic network after the first round of networking, multiple ranging values ​​of the newly added node in the dynamic network after the first round of networking within the sliding window L, the normalized variance of the newly added node, and the preset position of the newly added node, solve the objective function, and use the position corresponding to the minimum value of the objective function as the weighted estimated value of the position of the newly added node in the dynamic network after the first round of networking.

[0061] Furthermore, the objective function in S34 can be specifically expressed as:

[0062]

[0063] in,

[0064]

[0065] Among them, f(x i ) represents the objective function, x i represents the weighted estimated value of the position of the newly added node i, x j represents the actual location of neighbor base station j, r ij represents the estimated Euclidean distance between the newly added node i and the neighboring base station j, d ij represents the distance value between the newly added node i and the neighboring base station j, M represents the total number of neighboring base stations of the newly added node i, and A ij is the weight between the newly added node i and the neighboring base station j, reflecting the influence of signal fluctuation on the position estimation of the measured node, and σ represents the weight attenuation factor.

[0066] Specifically, in order to improve positioning accuracy and efficiency and enhance the robustness of dynamic networks, the DCL (Distributed Cooperative Localization) algorithm is adopted to distribute the calculation to each newly added node and its corresponding neighboring base station. Each newly added node communicates with the neighboring base stations within its communication range and obtains the ranging value and RSS value. The covariance of the ranging value and the covariance of the RSS value of the newly added node are calculated, and the normalized variance is further calculated. The objective function is constructed and solved. The position of the newly added node corresponding to the minimum value of the objective function is used as the weighted estimate of the position of the newly added node. The weighted estimate of the position of the newly added node is also the position of the newly added node in the two-dimensional plane coordinate system, thereby obtaining the self-built map after the first round of networking.

[0067] S4. Align the self-built map after the first round of networking with the known map using the ICP algorithm, find the point in the known map that best matches the newly added node in the self-built map after the first round of networking, and use the position of the point that best matches the newly added node as the position of the newly added node on the known map, thereby obtaining a dynamic map after the first round of networking; wherein each newly added node in the dynamic map after the first round of networking is a base station.

[0068] Specifically, the self-built map is aligned with the known map through the ICP (Iterative Closest Point) algorithm. For each new node in the self-built map after the first round of networking, the best matching point in the known map is found as the corresponding point, thereby achieving a one-to-one correspondence between each new node and the actual scene location, and obtaining a dynamic map after the first round of networking.

[0069] S5. Check the validity of each base station in the dynamic map after the first round of networking and count the total number of valid base stations after the first round of networking and the number of valid initial base stations among the valid base stations. Determine and update the initial base stations and the set of unnetworked nodes based on the total number of valid base stations after the first round of networking and the number of valid initial base stations among the valid base stations. Start the next round of networking at a preset networking time interval T. Repeat steps S2 to S4 until each node in the set of unnetworked nodes is networked, thereby obtaining a dynamic map consisting of several preset nodes.

[0070] Furthermore, in S5, the validity of each base station in the dynamic map after the first round of networking is checked and the total number of valid base stations after the first round of networking and the number of valid initial base stations among the valid base stations are counted, specifically including:

[0071] S51, randomly selecting a base station from the dynamic map after the first round of networking, and checking whether the selected base station can communicate within a preset sliding window L;

[0072] S52. If the selected base station can communicate within the preset sliding window L, the selected base station is a valid base station; otherwise, the selected base station is an invalid base station;

[0073] S53. Randomly select another base station from the dynamic map after the first round of networking, until all base stations in the dynamic map after the first round of networking are selected, and repeat steps S51 to S52 to obtain validity check results for all base stations;

[0074] S54. Count the total number of valid base stations after the first round of networking and the number of valid initial base stations among the valid base stations based on the validity check results of all base stations.

[0075] Preferably, in S5, judging and updating the initial base stations and the set of unnetworked nodes according to the total number of valid base stations after the first round of networking and the number of valid initial base stations among the valid base stations specifically includes:

[0076] If the total number of valid base stations in the dynamic map after the first round of networking is ≥ 3 and the number of valid initial base stations among the valid base stations is =3, then there is no need to update the initial base stations. The invalid base stations in the dynamic map after the first round of networking are added to the unnetworked node set.

[0077] Alternatively, if the total number of valid base stations in the dynamic map after the first round of networking is ≥3 and the number of valid initial base stations among the valid base stations is less than 3, the initial base stations need to be updated. Specifically, valid base stations with the same number as invalid initial base stations are selected from the dynamic map after the first round of networking as updated initial base stations, and the invalid base stations in the dynamic map after the first round of networking are added to the unnetworked node set.

[0078] Specifically, after obtaining the dynamic map after the first round of networking, it is necessary to check the validity of each base station in the dynamic map, count the total number of valid base stations, the number of valid initial base stations among the valid base stations, and determine:

[0079] 1) If the total number of valid base stations is ≥ 3, and the number of valid initial base stations among the valid base stations is 3, it means that there are no invalid initial base stations. In this case, there is no need to update the initial base stations. Instead, the invalid base stations in the dynamic map after the first round of networking are directly added to the set of unnetworked nodes. The next round of networking begins based on the dynamic map after the first round of networking.

[0080] 2) If the total number of valid base stations in the dynamic map after the first round of networking is ≥ 3, and the number of valid initial base stations among the valid base stations is less than 3, it means that there is an invalid initial base station. At this time, the lower-layer base stations directly connected to the invalid initial base station will be disconnected from the invalid initial base station, resulting in an incomplete network. To solve this problem, it is necessary to use the valid base stations in the dynamic map after the first round of networking to update the invalid initial base stations. The specific method is as follows:

[0081] If the lower-layer base station directly connected to the invalid initial base station is a valid base station, the invalid initial base station is deleted, and the valid base station directly connected to the invalid initial base station in the dynamic map after the first round of networking is used as the updated initial base station;

[0082] If the lower-layer base stations directly connected to the invalid initial base station are also invalid base stations, a corresponding number of base stations are randomly selected from other valid base stations in the network to replace the invalid initial base station.

[0083] The invalid base stations in the dynamic map after the first round of networking are added to the unnetworked node set, and the next round of networking is started based on the dynamic map after the first round of networking.

[0084] In addition, it should be noted that if the total number of valid base stations in the dynamic map after the first round of networking is less than 3 according to the validity check results of all base stations, there must be invalid initial base stations at this time, but there are no new lower-level valid base stations to replace them, then the first round of networking fails. At this time, it is necessary to return to step S1, arbitrarily select three nodes other than the failed base station from several nodes as the initial base stations and restart the networking.

[0085] The dynamic networking process of the first round of networking, the second round of networking and the third round of networking is as follows Figures 3 to 5 As shown in the figure, it can be clearly seen that as the number of networking rounds increases, the speed at which nodes join the network will become faster and faster, and the time required for networking will be greatly shortened, thereby improving efficiency.

[0086] The above-mentioned ultra-wideband communication and guidance integrated self-organizing networking method that adapts to complex unknown environments presets several nodes, arbitrarily selects three of the several nodes as initial base stations and constructs a two-dimensional plane coordinate system, obtains the positions of the three initial base stations in the two-dimensional plane coordinate system, and forms a non-networked node set with the remaining nodes in the several nodes. The sliding window and networking time interval are preset, and the three initial base stations send a broadcast signal for networking. Each node in the non-networked node set enters a monitoring state. If a broadcast signal for networking is received, a confirmation signal for networking is replied. After the three initial base stations receive the confirmation signal for networking, the non-networked node with the largest networking signal strength is selected for networking, and a dynamic network after the first round of networking is obtained. The initial base station's position in a two-dimensional coordinate system is used to calculate weighted estimates of the positions of newly added nodes in the dynamic network after the first round of networking, generating a self-built map after the first round of networking. The dynamic map after the first round of networking is then generated using the ICP algorithm based on the self-built map and the known map. The validity of each base station in the dynamic map after the first round of networking is checked. The initial base stations and the set of unnetworked nodes are determined and updated based on the total number of valid base stations after the first round of networking and the number of valid initial base stations among the valid base stations. The next round of networking begins at a preset networking interval T, and steps S2 through S4 are repeated until every node in the set of unnetworked nodes is networked, resulting in a dynamic map consisting of several preset nodes. The proposed signal strength-prioritized strategy ensures accurate positioning in each round of networking. The multi-layered network structure design, while taking into account the exploration range, allows for dynamic exploration of unnetworked nodes and handles node failures, enabling flexible base station deployment to cope with complex and changing unknown environments such as underground or battlefields.

[0087] The above is a detailed introduction to the ultra-wideband communication and guidance integrated self-organizing network method adapted to complex and unknown environments provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only intended to help understand the core ideas of the present invention. It should be noted that, for those skilled in the art, without departing from the principles of the present invention, several improvements and modifications may be made to the present invention, and such improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A method for ultra-wideband communication and guidance self-organizing network adapting to complex unknown environments, characterized by: The method comprises the following steps: S1. Preset a number of nodes, randomly select three of the nodes as initial base stations and construct a two-dimensional plane coordinate system, obtain the positions of the three initial base stations in the two-dimensional plane coordinate system, and form the remaining nodes from the number of nodes into an unnetworked node set; S2. Preset the sliding window L and networking time interval T to start the first round of networking: the three initial base stations send a network broadcast signal. Each node in the set of unnetworked nodes enters the listening state. If it receives the network broadcast signal, it replies with a network confirmation signal. After receiving the network confirmation signal, the three initial base stations select the unnetworked node with the strongest network signal strength to form a network, thus obtaining a dynamic network after the first round of networking. S3. Using the DCL algorithm, based on the positions of the three initial base stations in the two-dimensional plane coordinate system and a preset sliding window L, calculate weighted estimated values ​​of the positions of the newly added nodes in the dynamic network after the first round of networking, thereby obtaining a self-built map after the first round of networking; S4. Align the self-built map after the first round of networking with the known map using the ICP algorithm, find the point in the known map that best matches the newly added node in the self-built map after the first round of networking, and use the position of the point that best matches the newly added node as the position of the newly added node on the known map, thereby obtaining a dynamic map after the first round of networking; wherein each newly added node in the dynamic map after the first round of networking is a base station; S5. Check the validity of each base station in the dynamic map after the first round of networking and count the total number of valid base stations after the first round of networking and the number of valid initial base stations among the valid base stations. Determine and update the initial base stations and the set of unnetworked nodes based on the total number of valid base stations after the first round of networking and the number of valid initial base stations among the valid base stations. Start the next round of networking at a preset networking time interval T. Repeat steps S2 to S4 until every node in the set of unnetworked nodes is networked, thereby obtaining a dynamic map consisting of a number of preset nodes. In S5, the validity of each base station in the dynamic map after the first round of networking is checked and the total number of valid base stations after the first round of networking and the number of valid initial base stations among the valid base stations are counted, specifically including: S51, randomly selecting a base station from the dynamic map after the first round of networking, and checking whether the selected base station can communicate within a preset sliding window L; S52. If the selected base station can communicate within the preset sliding window L, the selected base station is a valid base station; otherwise, the selected base station is an invalid base station; S53. Randomly select another base station from the dynamic map after the first round of networking, until all base stations in the dynamic map after the first round of networking are selected, and repeat steps S51 to S52 to obtain validity check results for all base stations; S54. Count the total number of valid base stations after the first round of networking and the number of valid initial base stations among the valid base stations based on the validity check results of all base stations.

2. The method for ultra-wideband communication and guidance self-organizing network adapting to complex unknown environments according to claim 1, characterized in that: S3 specifically includes the following steps: S31. Construct an undirected weighted graph G based on the positions of the three initial base stations in the two-dimensional plane coordinate system and the newly added nodes in the dynamic network after the first round of networking, and calculate multiple ranging values ​​and multiple RSS values ​​of the newly added nodes in the dynamic network after the first round of networking within the sliding window L based on the undirected weighted graph G; S32, calculating the ranging value covariance and RSS value covariance of the newly added nodes in the dynamic network after the first round of networking according to the multiple ranging values ​​and multiple RSS values ​​of the newly added nodes in the sliding window L; S33, calculating the normalized variance of the newly added nodes using the Z-score method based on the ranging value covariance and RSS value covariance of the newly added nodes in the dynamic network after the first round of networking; S34. Preset the positions of the newly added nodes in the dynamic network after the first round of networking, establish an objective function based on the positions of the base stations in the dynamic network after the first round of networking, multiple ranging values ​​of the newly added nodes in the dynamic network after the first round of networking within the sliding window L, the normalized variance of the newly added nodes, and the preset positions of the newly added nodes, solve the objective function, and use the position corresponding to the minimum value of the objective function as a weighted estimated value of the position of the newly added nodes in the dynamic network after the first round of networking; S35, the positions of the three initial base stations in the two-dimensional plane coordinate system and the weighted estimated values ​​of the positions of the newly added nodes in the dynamic network after the first round of networking constitute the self-built map after the first round of networking.

3. The method for ultra-wideband communication and guidance self-organizing network adapting to complex unknown environments according to claim 2, characterized in that: The covariance of the ranging value and the covariance of the RSS value of the newly added node in S32 are specifically expressed as: Where Var() represents covariance, RSS ij is the signal strength value between the newly added node i and the neighboring base station j, d ij is the distance value between the newly added node i and the neighboring base station j, L represents the sliding window, is the kth ranging value between the newly added node i and the neighboring base station j, is the kth measured RSS value between the newly added node i and the neighboring base station j, k = 1, 2, ..., n(L), and n(L) represents the total number of ranging values ​​or RSS values ​​within the sliding window L.

4. The method for ultra-wideband communication and guidance self-organizing network adapting to complex unknown environments according to claim 3, characterized in that: In S33, the Z-score method is used to calculate the normalized variance of the newly added nodes. The normalized variance is specifically expressed as: Oh ij =ω1X(Var(RSS ij ))+ω2X(Var(d ij )) Where, Ω ij represents the normalized variance between the newly added node i and its neighboring base station j, X(*) represents the normalization function, and ω1 and ω2 are both normalized weight coefficients.

5. The method for ultra-wideband communication and guidance self-organizing network adapting to complex unknown environments according to claim 4, characterized in that: The objective function in S34 is specifically expressed as: in, Among them, f(x i ) represents the objective function, x i represents the weighted estimated value of the position of the newly added node i, x j represents the actual location of neighbor base station j, r ij represents the estimated Euclidean distance between the newly added node i and the neighboring base station j, d ij represents the distance value between the newly added node i and the neighboring base station j, M represents the total number of neighboring base stations of the newly added node i, and A ij is the weight between the newly added node i and the neighboring base station j, and σ represents the weight attenuation factor.

6. The method for ultra-wideband communication and guidance integrated ad hoc networking adapted to complex and unknown environments according to claim 5, characterized in that: In S5, the initial base stations and the set of unnetworked nodes are determined and updated based on the total number of valid base stations after the first round of networking and the number of valid initial base stations among the valid base stations, specifically including: If the total number of valid base stations in the dynamic map after the first round of networking is ≥ 3 and the number of valid initial base stations among the valid base stations is =3, then there is no need to update the initial base stations. The invalid base stations in the dynamic map after the first round of networking are added to the unnetworked node set. Alternatively, if the total number of valid base stations in the dynamic map after the first round of networking is ≥3 and the number of valid initial base stations among the valid base stations is less than 3, the initial base stations need to be updated. Specifically, valid base stations with the same number as invalid initial base stations are selected from the dynamic map after the first round of networking as updated initial base stations, and the invalid base stations in the dynamic map after the first round of networking are added to the unnetworked node set.

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