Ultra-wideband conduction integrated ad hoc network method adaptive to complex unknown environment

Abstract

The invention discloses an ultra-wideband conduction integrated ad hoc network method adaptive to a complex unknown environment, which comprises the following steps: presetting a plurality of nodes and randomly selecting three nodes as initial base stations, forming a non-networking node set by the residual nodes, sending networking broadcast signals by the three initial base stations, enabling the non-networking nodes to enter a monitoring state, and sending the monitoring broadcast signals to the initial base stations; the three initial base stations respectively select a non-networking node with the maximum networking signal intensity for networking, calculate a position weighted estimated value of a newly added node in a dynamic network obtained after the first round of networking and a dynamic map after the first round of networking, and check the validity of each base station in the dynamic map after the first round of networking; and judging and updating the initial base stations and the non-networking node set according to the total number of the effective base stations and the number of the effective initial base stations, starting the next round of networking at a preset networking time interval T, and repeating the process until all the non-networking nodes are networked to obtain a dynamic map consisting of a plurality of preset nodes. According to the method, the base station can be flexibly arranged so as to cope with a complex and changeable unknown environment.

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 the field of indoor positioning. However, UWB systems still face the challenge of signal network construction in complex and unknown environments, namely, ad hoc network design. Ad hoc network design refers to the design of a communication and navigation integrated ad hoc network method that can realize autonomous exploration, connection, coordination and management between network nodes and meet the requirements of flexible and reliable communication and navigation performance in response to the changes in network node topology and the rapid calibration and positioning requirements of base stations 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 communication and navigation integrated self-organizing network method that can adapt to complex and unknown environments, which can realize flexible base station layout and cope with complex and changeable unknown environments.

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

[0005] S1. Preset a number of nodes, select any 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;

[0006] S2, preset sliding window L and networking time interval T, start the first round of networking: three initial base stations send a broadcast signal for networking, each node in the non-networked node set enters a listening state, and if it receives a broadcast signal for networking, it replies with a confirmation signal for networking. After the three initial base stations receive the confirmation signal for networking, they select the non-networked node with the largest networking signal strength for networking, and obtain a dynamic network after the first round of networking;

[0007] S3, using the DCL algorithm to calculate the weighted estimated value of the position of the newly added nodes in the dynamic network after the first round of networking according to the positions of the three initial base stations in the two-dimensional plane coordinate system and the preset sliding window L, thereby obtaining the 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 through 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 unnetworked node set 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 unnetworked node set is networked, thereby obtaining a dynamic map consisting of several preset nodes.

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

[0011] S31, constructing an undirected weighted graph G according to 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 calculating multiple ranging values ​​and multiple RSS values ​​of the newly added nodes in the dynamic network after the first round of networking in the sliding window L according to the undirected weighted graph G;

[0012] S32, respectively 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 dynamic network after the first round of networking within the sliding window L;

[0013] S33, according to the covariance of the ranging values ​​and the covariance of the RSS values ​​of the newly added nodes in the dynamic network after the first round of networking, the normalized variance of the newly added nodes is calculated using the Z-score method;

[0014] S34, presetting the position of the newly added node in the dynamic network after the first round of networking, establishing an objective function according to 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, solving the objective function and taking 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;

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

[0017]

[0018] In the formula, 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 distance measurement 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, a Z-score method is used to calculate the normalized variance of the newly added node, and the normalized variance can be specifically expressed as:

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

[0021] In the formula, Ω ij represents the normalized variance between the newly added node i and the 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 neighboring 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 selecting 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, repeating steps S51 to S52, and obtaining validity check results of 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 according to the validity check results of all base stations.

[0032] Preferably, in S5, judging and updating the initial base stations and the unnetworked node set 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 = 3, there is no need to update the 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;

[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 integrated communication and navigation self-organizing method adapting to complex unknown environments presets a number of nodes, randomly 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, and 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 position of the initial base station in the two-dimensional plane coordinate system calculates the weighted estimated value of the position of the newly added nodes in the dynamic network after the first round of networking and obtains the self-built map after the first round of networking. The dynamic map after the first round of networking is obtained by 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 checked. The initial base station and the unnetworked node set are judged and updated according to the total number of valid base stations after the first round of networking and the number of valid initial base stations in the valid base stations. The next round of networking starts at a preset networking time interval T, and steps S2 to S4 are repeated until each node in the unnetworked node set is networked, thereby obtaining a dynamic map composed of several preset nodes. This method can dynamically explore unnetworked nodes and handle node failure problems, and realize flexible deployment of base stations to cope with complex and changeable unknown environments such as underground or battlefields. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

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

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

[0040] Figure 5 This is a schematic diagram of a dynamic network 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 in conjunction with the accompanying drawings.

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

[0043] S1. Preset a number of nodes, select any 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 O1, O2 and O3 are three randomly selected nodes. These three nodes are used as the initial base stations. The initial base station O1 is used as the coordinate origin, the direction of O1O2 is the X-axis direction, and the direction perpendicular to O1O2 is the Y-axis to build a two-dimensional plane coordinate system. The positions of the three initial base stations in the two-dimensional plane coordinate system are obtained. According to the principle of three-point positioning, the three initial base stations with known positions can measure the distance information and position information of any node. The remaining nodes are formed into a non-networked node set, and the flag bits of the remaining nodes 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 broadcast signal for networking, and each node in the non-networked node set enters a listening state. If a broadcast signal for networking is received, it replies with a signal to confirm networking. After the three initial base stations receive the signal to confirm networking, they select the non-networked node with the largest networking signal strength for networking, and obtain a dynamic network after the first round of networking.

[0046] Specifically, a sliding window L and a networking time interval T are preset. In the first round of networking, the three initial base stations O1, O2 and O3 send the networking broadcast signal in turn. 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 address of the non-networked node corresponding to each initial base station is recorded at this time, and 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 maximum 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 in the figure are directly connected to the three base stations through solid double arrows. The double arrows indicate that the nodes can communicate bidirectionally.

[0047] S3. The DCL (Distributed Cooperative Localization) algorithm is used to calculate the weighted estimated value of the position of the newly added nodes in the dynamic network after the first round of networking according to 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 according to 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 in the sliding window L according to 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 the neighbor node is the neighbor base station in the undirected weighted graph G that can directly communicate and measure the distance with the newly added node i. The mutual connection between each newly added node i and the neighbor base station j can be regarded as an edge (i,j), indicating that the newly added node i and the neighbor base station j can directly communicate and measure the distance. (i,j)∈ε, ε represents the set of edges in the undirected weighted graph G. After the first round of networking, the three base stations are all neighbor base stations of each newly added node. The multiple ranging values ​​of each newly added node in the preset sliding window can be measured by the position of the neighbor base station of each newly added node (that is, the position of the neighbor base station in the two-dimensional plane coordinate system), and the multiple RSS (Received Signal Strength) values ​​of each newly added node in the preset sliding window can be measured by the communication strength between each newly added node and the neighbor base station.

[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 dynamic network after the first round of networking within 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] In the formula, 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 distance measurement 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 farther the distance between the newly added node and its neighboring base stations, the lower the impact on the location estimation of the newly added node. The greater the signal strength of the neighboring base stations of the newly added node, the higher the impact on the location estimation of the newly added node. The smaller the covariance of the RSS value and the ranging value, the more stable the signal propagation and the higher the positioning accuracy.

[0056] S33. According to the ranging value covariance and RSS value covariance of the newly added nodes in the dynamic network after the first round of networking, the normalized variance of the newly added nodes is calculated using the Z-score method.

[0057] Furthermore, in order to solve the problem that the differences in numerical values ​​and dimensions between RSS values ​​and ranging values ​​affect the positioning accuracy, the Z-score method is used to obtain the normalized variance of the RSS value and ranging value after the measurement 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] In the formula, Ω ij represents the normalized variance between the newly added node i and the 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 larger the fluctuation, the smaller the normalized weight coefficient, which 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 positions of newly added nodes in the dynamic network after the first round of networking, establish an objective function according to the positions of base stations in the dynamic network after the first round of networking, multiple ranging values ​​of 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 the weighted estimate of the position of the newly added nodes 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 neighboring 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 the positioning accuracy and efficiency and enhance the robustness of the dynamic network, the DCL (Distributed Cooperative Localization) algorithm is adopted to distribute the operation to each newly added node and its corresponding neighbor base station. Each newly added node communicates with the neighbor base stations within its communication range and obtains the ranging value and RSS value, calculates the ranging value covariance and RSS value covariance of the newly added node, and further calculates the normalized variance, constructs the objective function and solves the objective function, and takes the position of the newly added node corresponding to the minimum value of the objective function as the weighted estimate of the position of the new node. The weighted estimate of the position of the new node is also the position of the new 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 through 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, so as to achieve a one-to-one correspondence between each new node and the actual scene position, and obtain 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 unnetworked node set 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 unnetworked node set 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 selecting 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, repeating steps S51 to S52, and obtaining validity check results of 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 according to the validity check results of all base stations.

[0075] Preferably, in S5, judging and updating the initial base stations and the unnetworked node set 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 = 3, there is no need to update the 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;

[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, and 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. At this time, 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 directly 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;

[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 base station directly connected to the failed initial base station will be disconnected from the failed initial base station, resulting in an incomplete network. In order 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, and it is necessary to return to step S1, arbitrarily select three nodes other than the failed base station from a number of 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 integrated communication and navigation self-organizing method adapting to complex unknown environments presets a number of nodes, randomly 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, and 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 position of the initial base station in the two-dimensional plane coordinate system calculates the weighted estimated value of the position of the newly added nodes in the dynamic network after the first round of networking and obtains the self-built map after the first round of networking. The dynamic map after the first round of networking is obtained by 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 checked. The initial base station and the unnetworked node set are judged and updated according to the total number of valid base stations after the first round of networking and the number of valid initial base stations in the valid base stations. The next round of networking starts at a preset networking time interval T, and steps S2 to S4 are repeated until each node in the unnetworked node set is networked, thereby obtaining a dynamic map composed of several preset nodes. The signal strength priority strategy proposed in the method ensures the accuracy of each round of networking positioning. At the same time, the multi-level network structure design takes into account the exploration range, can dynamically explore unnetworked nodes and handle node failure problems, and realize flexible deployment of base stations to cope with complex and changeable unknown environments such as underground or battlefields.

[0087] The above is a detailed introduction to an ultra-wideband communication and guidance integrated self-organizing network method adapted to complex unknown environments provided by the present invention. This article uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the core idea of ​​the present invention. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, the present invention can also be improved and modified, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A self-organizing method for ultra-wideband communication and guidance that adapts to complex and unknown environments, characterized in that: The method comprises the following steps: S1. Preset a number of nodes, select any 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; S2, preset sliding window L and networking time interval T, start the first round of networking: three initial base stations send a broadcast signal for networking, each node in the non-networked node set enters a listening state, and if it receives a broadcast signal for networking, it replies with a confirmation signal for networking. After the three initial base stations receive the confirmation signal for networking, they select the non-networked node with the largest networking signal strength for networking, and obtain a dynamic network after the first round of networking; S3, using the DCL algorithm to calculate the weighted estimated value of the position of the newly added nodes in the dynamic network after the first round of networking according to the positions of the three initial base stations in the two-dimensional plane coordinate system and the preset sliding window L, thereby obtaining the 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 through 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 unnetworked node set 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 unnetworked node set is networked, thereby obtaining a dynamic map consisting of several preset nodes.

2. The method for ultra-wideband communication and guidance integrated self-organizing network adapting to complex unknown environments as claimed in claim 1, characterized in that: S3 specifically includes the following steps: S31, constructing an undirected weighted graph G according to 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 calculating multiple ranging values ​​and multiple RSS values ​​of the newly added nodes in the dynamic network after the first round of networking in the sliding window L according to the undirected weighted graph G; S32, respectively 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 dynamic network after the first round of networking within the sliding window L; S33, according to the covariance of the ranging values ​​and the covariance of the RSS values ​​of the newly added nodes in the dynamic network after the first round of networking, the normalized variance of the newly added nodes is calculated using the Z-score method; S34, presetting the position of the newly added node in the dynamic network after the first round of networking, establishing an objective function according to 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, solving the objective function and taking 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; 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 integrated self-organizing network adapting to complex unknown environments as claimed in claim 2, characterized in that: The covariance of the distance measurement value and the covariance of the RSS value of the newly added node in S32 can be specifically expressed as: In the formula, 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 distance measurement 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 integrated self-organizing network adapting to complex unknown environments as claimed in 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 can be specifically expressed as: Oh ij =ω1X(Var(RSS ij ))+ω2X(Var(d ij )) In the formula, Ω ij represents the normalized variance between the newly added node i and the 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 integrated self-organizing network adapting to complex unknown environments as claimed in claim 4, characterized in that: The objective function in S34 can be 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 neighboring 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 self-organizing network adapting to complex unknown environments as claimed in claim 5, characterized in that: 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 selecting 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, repeating steps S51 to S52, and obtaining validity check results of 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 according to the validity check results of all base stations.

7. The method for ultra-wideband communication and guidance integrated self-organizing network adapting to complex unknown environments as claimed in claim 6, characterized in that: In S5, the initial base stations and the unnetworked node set are determined and updated 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 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 = 3, there is no need to update the 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; 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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