Method and system for constructing mobile network based on unmanned aerial vehicle

Abstract

The application belongs to the technical field of unmanned aerial vehicles, and specifically discloses a mobile network construction method and system based on unmanned aerial vehicles, which comprises the following steps: according to the performance parameters of unmanned aerial vehicles, the flight track of a single unmanned aerial vehicle is planned and set in advance, so that the unmanned aerial vehicle can sail according to a spherical or elliptical track within a preset space range; according to the network demand range, the required cloud-shaped 'aircraft chain' network area and the number of unmanned aerial vehicle base stations required in the 'aircraft chain' are calculated; according to the travel form and route of the network demand side, the shape, moving direction and speed of the cloud-shaped 'aircraft chain' network are overall planned; the unmanned aerial vehicles are classified and divided into different states, the number of unmanned aerial vehicles of different categories is determined, and the mobile network is constructed by using the determined unmanned aerial vehicles of different categories to carry communication base stations. By adopting the technical scheme, the cloud-shaped 'aircraft chain' network of a certain area is constructed in the air, the coverage range coincidence degree is improved, and the problem that the movement of the ground vehicle-mounted base station is limited by road conditions is solved.

Description

Technical Field

[0001] This invention belongs to the field of unmanned aerial vehicle (UAV) technology and relates to a method and system for constructing a mobile network based on UAVs. Background Technology

[0002] Currently, 5G mobile communication networks primarily rely on vehicle-mounted base stations for mobility or drone-borne base stations to provide mobile signals. However, the construction and operation of current 5G mobile communication networks still face the following challenges:

[0003] 1. The mobility of ground-based mobile base stations is greatly restricted by ground road conditions. In addition, whether it is a ground-based mobile base station or an airborne mobile base station, the overlap of signal coverage is small, and there are situations where the signal is weak at some points.

[0004] 2. Current drones equipped with 5G base stations require a certain time interval for replacement response when they malfunction or are damaged.

[0005] 3. When current drones are equipped with 5G base stations and move in the air, their flight trajectory is controlled by the operator. The drones have a high degree of randomness in flight, poor autonomy, and poor network stability.

[0006] 4. Current drones equipped with 5G base stations do not have intelligent features during aerial movement, and obstacle avoidance still requires the operator's intervention.

[0007] 5. The existing 5G base stations on drones are isolated from each other and cannot communicate with each other, resulting in poor overall integration.

[0008] 6. The drones lack necessary protective measures. Summary of the Invention

[0009] The purpose of this invention is to provide a method and system for constructing mobile networks based on unmanned aerial vehicles (UAVs) to improve coverage overlap.

[0010] To achieve the above objectives, the basic solution of the present invention is: a method for constructing a mobile network based on unmanned aerial vehicles (UAVs), comprising the following steps:

[0011] Based on the performance parameters of the drone, the flight path of a single drone is pre-planned and set, so that it can glide autonomously in a spherical or elliptical trajectory within a preset space.

[0012] Based on the network demand range, calculate the required cloud-like "machine chain" network area and the number of drone base stations required within the "machine chain";

[0013] Based on the movement patterns and routes of network demanders, the overall planning of the cloud-like "machine chain" network shape, movement direction, and speed is carried out;

[0014] The unmanned aerial vehicle is classified and divided into categories and states, the number of unmanned aerial vehicles of different categories is determined, the unmanned aerial vehicles of different categories are determined to carry communication base stations, and a mobile network is constructed.

[0015] The working principle and beneficial effects of the basic scheme are that: according to the performance parameters (such as maximum turning radius, pitch angle) of different models of unmanned aerial vehicles, the flight trajectory of a single intelligent unmanned aerial vehicle is pre-planned and set by control software, so that it can independently cruise in a certain space range (vertically and horizontally) according to a spherical or elliptical trajectory. It is suitable for the flight characteristics of unmanned aerial vehicles and can ensure that the cloud-like "machine chain" network signal coverage rate is not affected when the running track is moderately changed.

[0016] Further, the method for calculating the required cloud-like "machine chain" network area according to the network demand range is:

[0017] S=A*B

[0018] Wherein, S is the area of the cloud-like "machine chain" network, A is the area of the protected area, and B is the terrain environment adjustment coefficient.

[0019] Reasonably determine the area of the cloud-like "machine chain" network to ensure that the area of the cloud-like "machine chain" network is appropriately larger than the area of the protected area.

[0020] Further, the number of "machine chain" base stations is:

[0021]

[0022] Wherein, b is the number of "machine chain" unmanned aerial vehicle base stations, T is the coincidence adjustment coefficient, K is the effective coverage area of a single "machine chain" base station; A is the area of the protected area, B is the terrain environment adjustment coefficient, E is the environment correction coefficient, and L is the network load adjustment coefficient.

[0023] The coincidence adjustment coefficient is introduced to reasonably determine and control the coincidence degree of the coverage area of adjacent base stations.

[0024] Further, according to the marching form and route of the network demand side, the shape, moving direction and speed of the cloud-like "machine chain" network are planned as a whole, and the specific steps are:

[0025] When the network demand side marches along one or more columns, the shape of the cloud-like "machine chain" network should take the middle point of the marching column of the network demand side as the reference point, extend forward and backward, and present in a strip shape, consistent with the column;

[0026] When the network demand side marches in a group, the cloud-like "machine chain" network should take the center point of the group as the center of the circle and present in a cloud shape;

[0027] Let the group center point P g (t) be:

[0028] P g (t) = (x g (t), y g (t))

[0029] wherein x g (t), y g (t) are the coordinates of the center point at time t;

[0030] The shape S c (t) of the cloud-like "machine chain" network represents a circle with P g (t) as the center and r(t) as the radius:

[0031] S c (t) = πr(t) 2

[0032] wherein r(t) is dynamically adjusted according to changes in group size, travel speed, and network demand:

[0033] r(t) = (α·N(t) + β·v(t) + γ·D(t))·exp(-λt)

[0034] wherein N(t) is the group size, i.e., the size of the user or group at time t; v(t) represents the travel speed of the group, i.e., the moving speed of the group at time t; D(t) represents the network demand, i.e., the network bandwidth demand at time t; α, β, γ are corresponding weight coefficients, reflecting the relative importance of each factor on r(t); λ is a decay factor used to simulate the influence of time on group size, speed, and demand. As time passes, the network demand may change, and the decay factor is used to adjust this change;

[0035] The moving direction of the cloud-like "machine chain" network is consistent with the travel direction and speed of the network demand side. With the help of geographic information systems, the travel direction of the network demand side is obtained in real time;

[0036] The drones maintain a spherical or elliptical flight trajectory and roll forward in synchronization with the moving direction of the network demand side;

[0037] All drones in the cloud-like "machine chain" move synchronously and as a whole;

[0038] The drones obtain the travel speed information of the network demand side in real time;

[0039] When the travel speed of the network demand side changes, the control terminal changes and regulates the moving speed of the cloud-like "machine chain" network to make it change synchronously with the travel speed of the network demand side.

[0040] The moving speed of the cloud-like "machine chain" network is changed and regulated in real time to make it change synchronously with the travel speed of the network demand side, meeting the use demand.

[0041] Further, the unmanned aerial vehicles are divided into:

[0042] One-bit machine, corresponding to online state;

[0043] Two-bit machine, corresponding to quasi-online state;

[0044] Three-bit machine, corresponding to standby state;

[0045] An automatic repair method is adopted to realize the function connection of damaged unmanned aerial vehicles with faults or damages, i.e. two-bit machine enters one-bit machine to participate in network connection;

[0046] The number of one-bit machines is R1, i.e. the number of base stations b of the cloud-shaped "machine chain" network;

[0047] The number of two-bit machines is R2, which is less than the number of one-bit machines, and is:

[0048] R2=R1*P1

[0049] Wherein, R2 is the number of two-bit machines, R1 is the number of one-bit machines, and P1 is a two-bit machine number adjustment system;

[0050] The number of three-bit machines is R3, which is less than the number of two-bit machines, and is:

[0051] R3=R2*P2

[0052] Wherein, R3 is the number of three-bit machines, R2 is the number of two-bit machines, and P2 is a three-bit machine number adjustment coefficient.

[0053] The division of unmanned aerial vehicles is beneficial to control.

[0054] Further, the automatic repair method is:

[0055] Let the state of each node in the unmanned aerial vehicle network be S i , i=1, 2, …, N, and each node can be in one of two states:

[0056] S i =1: node i works normally;

[0057] S i =0: node i has a fault or is damaged;

[0058] Let the topology matrix of the unmanned aerial vehicle network be T1, wherein each element T ij represents the connectivity from node i to node j, 1 represents connectivity, and 0 represents non-connectivity; when a fault occurs, the topology needs to be adjusted as:

[0059] T'=T1·ΔS

[0060] Wherein, Delta S indicates the node state vector that needs to be adjusted after the fault is sent, T' is the adjusted topology matrix;

[0061] Based on the reliability and power consumption of the nodes, the node with the highest score is selected to make up for the vacancy:

[0062] Score j = alpha 1 cdot R j + beta 1 cdot E j

[0063] Wherein, alpha 1 and beta 1 are weight factors, R j And E j Respectively indicate the reliability and remaining power of node j, Score j For the score of the jth node.

[0064] The automatic vacancy-filling method is used to ensure the network reliability.

[0065] Further, the method for constructing a mobile network by using the determined unmanned aerial vehicles of different categories to carry communication base stations is specifically:

[0066] When the cloud-shaped'machine chain' network moves, if an aerial object or other foreign matter is encountered, the sensor senses the position, height and speed information of the surrounding aerial object or other foreign matter, and according to the position, height and speed of the unmanned aerial vehicle, the unmanned aerial vehicle performs automatic obstacle avoidance and automatic obstacle circumvention protection actions accordingly;

[0067] The unmanned aerial vehicle has an interference signal self-sensing function, and adjusts the transmission frequency according to the strength of the interference signal, and when the interference signal is strong, the transmission frequency is increased accordingly.

[0068] The wireless broadband tactical ad hoc network technology is used to enable all the aerial'machine chain' base stations to construct a self-organizing network, each base station can dynamically create a new chain lock, automatically construct and quickly deploy a new regional network, and enhance the stability and practicability of the entire network.

[0069] Further, according to the distribution of the personnel and equipment to be protected, a sketch map based on the distribution range of the personnel and equipment to be protected is automatically generated, specifically:

[0070] The position information of the personnel and equipment to be protected is collected, including the position coordinates of each object;

[0071] The spatial distribution range of the personnel and equipment to be protected is determined through the extreme points MinX, MaxX, MinY and MaxY:

[0072] MinX = min(x1, …, x N+M ), MaxX = max(x1, …, x N+M )

[0073] MinY=min(y1,..., y N+M ), MaxY=max(y1,..., y N+M )

[0074] calculating the heat map density D ij :

[0075]

[0076] wherein x N+M and y N+M are the horizontal and vertical coordinates of the object to be guaranteed; COG(ij) is the number of objects to be guaranteed contained in the grid unit in the i-th row and j-th column, the spatial distribution range is divided into a plurality of grid units, the size of each grid unit is Δx*Δy, each network unit is assigned a color value, and a graph is generated.

[0077] Based on the sketch map, a cloud-shaped "machine chain" network plan is generated, taking the center point of the cloud-shaped "machine chain" network plan as the origin to establish a plane coordinate system, and then a new z-axis is established based on the plane coordinate system to form a three-dimensional coordinate system, so that a three-dimensional coordinate system of the unmanned aerial vehicle base station layout is obtained;

[0078] When the distribution of the object to be guaranteed changes, a new distribution range sketch map based on the changed object to be guaranteed is generated again according to the change of the object to be guaranteed, and a new cloud-shaped "machine chain" network plan is generated based on the new distribution range sketch map;

[0079] A new plane coordinate system is established taking the center point of the newly generated network plan as the origin, and then a new z-axis is established based on the new plane coordinate system to form a new three-dimensional coordinate system, so that a new three-dimensional coordinate system of the unmanned aerial vehicle base station layout is obtained;

[0080] According to the coordinate values of the unmanned aerial vehicle base station in the new three-dimensional coordinate system, all the unmanned aerial vehicle base stations can be repositioned, and the "repositioning" is "executed", so that all the unmanned aerial vehicle base stations can find appropriate positions, and the shape of the entire cloud-shaped "machine chain" network is changed accordingly to match the change of the distribution of the object to be guaranteed.

[0081] The position change based on the coordinate system is beneficial to control operation.

[0082] The application also provides an unmanned aerial vehicle-based mobile network construction system based on the method, which comprises an unmanned aerial vehicle, a base station, a ground control station, a "machine chain" terminal and a user terminal.

[0083] The unmanned aerial vehicle has the function of self-adjusting flight state in real time, and realizes intercommunication between unmanned aerial vehicles through wireless broadband ad hoc network technology.

[0084] The base station is arranged on the unmanned aerial vehicle, and is used for continuously transmitting and receiving network signals to a certain area.

[0085] The ground control station is divided into a fixed station and a mobile station, the fixed station is arranged at a fixed point, and the mobile station is arranged at a mobile point.

[0086] The "machine chain" terminal includes a fixed "machine chain" terminal and a mobile "machine chain" terminal, and the mobile "machine chain" terminal is used for realizing uninterrupted network connection with the base station.

[0087] The user terminal includes various application software systems and various devices supporting the operation of the application software systems, and the application software systems meet the task requirements of different tasks and different professional teams.

[0088] The system has simple structure, uses the intelligent unmanned aerial vehicle to carry the communication base station, so that the constructed cloud-shaped "machine chain" network has strong intelligent characteristics, uses the wireless broadband tactical ad hoc network technology, so that all the "machine chain" base stations in the air construct a self-organizing network, and are integrated vertically (to the ground) and horizontally (around the space).

[0089] Further, the ground control station includes a control platform, a control antenna, a gateway station and a data antenna.

[0090] The control platform is used for dividing unmanned aerial vehicle categories and grouping, planning a running route, adjusting an attitude, controlling a speed, deploying different types of unmanned aerial vehicle quantities, the control antenna is connected with the control antenna of the unmanned aerial vehicle, the linkage between the unmanned aerial vehicle and the ground control station is realized, and the transmission of the adjustment control signal is completed.

[0091] The gateway station is used for connecting the base station and the wired network, realizing the access and control of the wired network.

[0092] The data antenna is connected with the base station, and the linkage between the wired network and the base station is realized.

[0093] The ground control station is divided into a fixed station and a mobile station, realizes the linkage between the wired network and the "machine chain" base station, and meets the use requirements.

[0094] Further, the "machine chain" terminal includes an antenna and a router, the antenna adopts a portable support, and is used for realizing network connection with the base station in the air.

[0095] The router is provided with multiple frequency bands and multiple gigabit network interfaces, supports simultaneous access of 50-100 user terminal devices, and is used for realizing connection with the user terminal.

[0096] The mobile "air chain" terminal is used for realizing different network connections with the "air chain" base station in motion, and is suitable for being used on mobile platforms such as airplanes, ships and vehicles. BRIEF DESCRIPTION OF DRAWINGS

[0097] Figure 1 is a flow diagram of the mobile network construction method based on the unmanned aerial vehicle of the present application. DETAILED DESCRIPTION

[0098] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the drawings, wherein the same or similar notations represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary, and are only used for explaining the present application, and cannot be understood as limiting the present application.

[0099] In the description of the present application, it should be understood that the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0100] In the description of the present application, unless otherwise specified and limited, it should be noted that the terms "mounting", "connection" and "connection" should be understood broadly, for example, they can be mechanical connection or electrical connection, or the communication between the two elements, or direct connection, or indirect connection through an intermediate medium, and the specific meaning of the above terms can be understood by those skilled in the art according to the specific circumstances.

[0101] The present application discloses a mobile network construction method based on unmanned aerial vehicles, which uses unmanned aerial vehicles to carry communication base stations to construct a cloud-like "air chain" network in a certain area in the air, improves the coverage range coincidence degree, solves the problem of road condition restriction of ground vehicle-mounted base station movement, and the problem of local signal weakening. As shown in Figure 1 The mobile network construction method based on unmanned aerial vehicles includes the following steps:

[0102] According to the performance parameters (such as maximum turning radius, pitch angle, etc.) of different models of unmanned aerial vehicles, the flight trajectory of a single unmanned aerial vehicle is pre-planned and set, so that it can sail in a spherical or elliptical trajectory within a pre-set space range (vertically and horizontally); both the flight characteristics of the unmanned aerial vehicle and the signal coverage rate of the cloud-like "air chain" network can be ensured when the running trajectory is moderately changed.

[0103] The method for specifically pre-planning and setting the flight track of the single unmanned aerial vehicle is as follows:

[0104] The unmanned aerial vehicle at the network periphery adopts an elliptical track, and the remaining unmanned aerial vehicles adopt a spherical track;

[0105] The size of the flight range is set, including the radius in the vertical direction (height) and the horizontal direction. If the flight track of the unmanned aerial vehicle is a circle, the radius r of the flight of the unmanned aerial vehicle is set, and the center position of the flight track is C(x0, y0, z0). The spherical track equation is as follows:

[0106] (x-x0) 2 +(y-y0) 2 +(z-z0) 2 =r 2

[0107] Wherein, x, y, z are the current position coordinates of the unmanned aerial vehicle, and r is the radius of the track.

[0108] If the flight track of the unmanned aerial vehicle is an ellipse, the long axis of the ellipse is a, the short axis is b, and the parametric equation of the ellipse is as follows:

[0109]

[0110] Wherein, x0, y0 are the coordinates of the center of the ellipse.

[0111] According to the network demand range (for example, the network needs to be established within a range of 100 kilometers), the required cloud-shaped "machine chain" network area and the number of unmanned aerial vehicle base stations required in the "machine chain" are calculated;

[0112] According to the travel form and route of the network demand party, the shape, moving direction and speed of the cloud-shaped "machine chain" network are overall planned.

[0113] The unmanned aerial vehicles are classified and divided into states, the number of unmanned aerial vehicles of different categories is determined, the communication base stations are carried by the determined unmanned aerial vehicles of different categories, and the mobile network is constructed.

[0114] In a preferred scheme of the application, the method for calculating the required cloud-shaped "machine chain" network area according to the network demand range is as follows:

[0115] S=A*B

[0116] Wherein, S is the cloud-like "machine chain" network area, A is the security area, and B is the terrain environment adjustment coefficient. Generally, the value of B is 120%-150%. In general terrain or environment, the value of B is not less than 120%; in complex terrain or environment, the value of B should be slightly higher, and the highest value should not exceed 150%. In the calculation formula, the terrain environment adjustment coefficient B is introduced, the purpose of which is to reasonably determine the cloud-like "machine chain" network area, and to ensure that the cloud-like "machine chain" network area is appropriately larger than the area of the security area.

[0117] The terrain environment adjustment coefficient B = TT x D x W x F

[0118] Wherein, the parameter TT is the terrain type, D is the building density, W is the weather condition, and F is the signal frequency. The specific parameters can be adjusted according to the actual situation. For example:

[0119] The terrain type TT is 0.5 in mountainous areas, 0.7 in urban areas, and 1 in flat areas.

[0120] Building density D: when the building density is high, the value range is 0.7-0.9, and the value in low building density areas is 1.

[0121] Weather condition W: the value is 1 in sunny weather, and 0.8 or lower in rainy and snowy weather.

[0122] Signal frequency F: signals with lower frequency (such as 800MHz) have better propagation characteristics, and the value is 1; signals with higher frequency (such as 2.4GHz) have lower values, about 0.7-0.9.

[0123] Preferably, the number of "machine chain" base stations is:

[0124]

[0125] Wherein, b is the number of "machine chain" base stations, T is the coincidence adjustment coefficient (which can be set artificially), K is the effective coverage area of a single "machine chain" base station; A is the security area, B is the terrain environment adjustment coefficient, E is the environment correction coefficient, and L is the network load adjustment coefficient.

[0126]

[0127] Wherein, N1 is the number of currently connected users or network load; and C1 is the maximum user processing capacity or network capacity of the base station.

[0128] Generally, T is in the range of 20%-30%. In the environment without strong electromagnetic interference, T is not less than 20%; in the complex environment or the environment with strong electromagnetic interference, T should be slightly higher, and the highest value should not be more than 10%. In the calculation formula, the coincidence degree adjustment coefficient is introduced, and the purpose is to reasonably determine and control the coincidence degree of the coverage area of adjacent base stations. The environmental correction coefficient E is obtained by weighting and summing the factors such as weather, terrain, building density, vegetation coverage, etc., and can be obtained by prior experiment.

[0129] In a preferred scheme of the application, according to the traveling form and route of the network demand side, the overall planning of the cloud-shaped "machine chain" network shape, moving direction and speed is carried out, and the specific steps are as follows:

[0130] When the network demand side advances along one or more columns, the cloud-shaped "machine chain" network shape should take the middle point of the network demand side traveling column as the reference point, extend forward and backward, and present in a strip shape, consistent with the column;

[0131] When the network demand side advances in the form of a group column, the cloud-shaped "machine chain" network should take the center point of the group column as the center, and present in the form of a cloud cluster;

[0132] Let the group center point P g (t) be:

[0133] P g (t) = (x g (t), y g (t))

[0134] Where x g (t), y g (t) are the coordinates of the center point at time t;

[0135] The shape S c (t) of the cloud-shaped "machine chain" network represents a circle with P g (t) as the center and r(t) as the radius:

[0136] S c (t) = πr(t) 2

[0137] Where r(t) is dynamically adjusted according to the group size, traveling speed and network demand changes:

[0138] r(t) = (α·N(t) + β·v(t) + γ·D(t))·exp(-λt)

[0139] Wherein, N(t) is the group size, that is, the user or group size at t moment; V(t) represents the group travel speed, that is, the moving speed of the group at t moment; D(t) represents the network demand, that is, the network bandwidth demand at t moment (can be determined according to the sum of the bandwidth demand of the network demand users in the group multiplied by the redundancy coefficient); Alpha, beta, gamma are corresponding weight coefficients, reflecting the relative importance of each factor to r(t), which can be set in advance; Lambda is a decay factor.

[0140] The moving direction of the cloud-shaped ''machine chain'' network is consistent with the moving direction and speed of the network demand side, and the moving direction of the network demand side is obtained in real time by means of a geographic information system;

[0141] The unmanned aerial vehicle keeps a spherical or elliptical flight trajectory and synchronously rolls forward along the moving direction of the network demand side;

[0142] All unmanned aerial vehicles of the cloud-shaped ''machine chain'' move synchronously and integrally.

[0143] The unmanned aerial vehicle obtains network demand side travel speed information in real time.

[0144] When the network demand side travel speed changes, the control terminal changes and regulates the moving speed of the cloud-shaped ''machine chain'' to make it change synchronously with the network demand side travel speed.

[0145] In a preferred scheme of the application, the unmanned aerial vehicles are divided into:

[0146] One machine corresponds to an online state; one machine refers to an intelligent unmanned aerial vehicle that is in a corresponding height and in a running state (participates in network connection), and the height is usually 3000-5000 meters.

[0147] Two machines correspond to a quasi-online state; two machines refer to intelligent unmanned aerial vehicles that are on standby at a corresponding height and are ready to fill vacancies at any time, and the height is usually 5000-10000 meters.

[0148] Three machines correspond to a standby state; three machines refer to intelligent unmanned aerial vehicles that are waiting for instructions to take off on the ground, and usually after the two machines fill the vacancies to one machine, the ground control station issues instructions to enter the two machine sequence according to the plan. All intelligent unmanned aerial vehicles have the function of adjusting their flight state in real time and automatically, and realize intercommunication and interconnection between unmanned aerial vehicles through wireless broadband tactical ad hoc network technology.

[0149] The automatic vacancy filling method is adopted to realize the function connection of damaged or malfunctioning unmanned aerial vehicles, that is, two machines enter one machine to participate in network connection; or the manual regulation method can be adopted to realize the unmanned aerial vehicle category adjustment (that is, from three machines to two machines) and state change (that is, from standby state to quasi-online state), so as to solve the problem of long replacement reaction time interval.

[0150] The number of one-bit machines is R1, that is, the number of base stations of the cloud-shaped ''machine chain'' network;

[0151] The number of two-bit machines is R2, which is less than the number of one-bit machines, and is:

[0152] R2=R1*P1

[0153] Wherein, R2 is the number of two-bit machines, R1 is the number of one-bit machines, and P1 is a two-bit machine number adjustment system;

[0154] The number of three-bit machines is R3, which is less than the number of two-bit machines, and is: usually, the value range of P1 is 40%-60%. The value should be determined according to the countermeasure technology and means of the opponent unmanned aerial vehicle, and if necessary, the value of P1 can also exceed the above range.

[0155] R3=R2*P2

[0156] Wherein, R3 is the number of three-bit machines, R2 is the number of two-bit machines, and P2 is a three-bit machine number adjustment coefficient. Usually, the value range of P2 is 20%-50%. The value should be determined according to the countermeasure technology and means of the opponent unmanned aerial vehicle, and if necessary, the value of P2 can also exceed the above range. When the unmanned aerial vehicle fails or is damaged, the two-bit machine timely fills the vacancy, greatly shortens the replacement reaction time interval, and ensures the continuity and stability of the network.

[0157] Reasonably determine the area and shape of the cloud-shaped ''machine chain'' network, improve the signal coverage range coincidence degree, and ensure that there is no signal blind area in any point in the coverage range.

[0158] In a preferred scheme of the application, the automatic vacancy filling method is:

[0159] Let the state of each node in the unmanned aerial vehicle network be S i , i=1, 2, …, N, and each node can be in one of the two states:

[0160] S i =1: node i works normally;

[0161] S i =0: node i fails or is damaged;

[0162] For the failed node, select other nodes to take over its task, which can be realized through a redundant compensation mechanism. Let the topology matrix of the unmanned aerial vehicle network be T1, wherein each element T ij represents the connectivity from node i to node j, 1 represents connectivity, and 0 represents non-connectivity; when a fault occurs, the topology needs to be adjusted as follows:

[0163] T'=T1*Delta S

[0164] Where ΔS represents the node state vector that needs to be adjusted after the fault is sent, and T′ is the adjusted topology matrix;

[0165] Based on node reliability and power consumption, the node with the highest score is selected to fill the gap:

[0166] Score j =α1·R j +β1·E j

[0167] Here, α1 and β1 are weighting factors, which can be preset. R j and E j Score represents the reliability and remaining power of node j, respectively. j The score for the j-th node.

[0168] In a preferred embodiment of the present invention, the method for constructing a mobile network by using different types of drones equipped with communication base stations is specifically as follows:

[0169] When the cloud-like "machine chain" network encounters flying objects or other foreign objects during its movement, it uses sensors to perceive the position, altitude, and speed of the surrounding flying objects or other foreign objects. Based on its own position, altitude, and speed, it performs automatic obstacle avoidance and obstacle bypass protective actions accordingly. By relying on intelligent drones, the cloud-like "machine chain" network is endowed with intelligent features, improving its autonomous movement capabilities, as well as its obstacle avoidance and obstacle bypass capabilities.

[0170] The drone possesses interference signal self-sensing capabilities, automatically adjusting its transmission frequency based on the strength of the interference signal. When the interference signal is strong, the transmission frequency increases accordingly. For example, when there are many interference sources or strong interference signals, it can automatically and appropriately increase its operating frequency to ensure that its signal strength meets communication requirements. This enables the "drone-chain" base station to adaptively adjust its power.

[0171] By utilizing wireless broadband tactical self-organizing network technology, all airborne "machine-chain" base stations can build a self-organizing network, connecting vertically (towards the ground) and horizontally (around space). Each base station can dynamically create new chains, automatically build and quickly deploy new regional networks, and achieve information forwarding and exchange through "multi-hop" methods, enhancing the stability and usability of the entire network.

[0172] The cloud-like "machine chain" network changes synchronously with the direction and speed of the troops' movement, achieving full-process dynamic support with no signal blind spots and good support efficiency.

[0173] In a preferred embodiment of the present invention, the "UAV (base station) allocation module" automatically generates a rough map based on the distribution range of the personnel and equipment of the target beneficiaries, specifically:

[0174] Collect the location information of the objects to be protected, including the location coordinates (e.g., x, y) of each object;

[0175] The spatial distribution range of the object to be protected is determined by using the extreme points MinX, MaxX, MinY, and MaxY.

[0176] MinX = min(x1, ..., x) N+M MaxX = max(x1, ..., x) N+M )

[0177] MinY = min(y1, ..., y) N+M MaxY = max(y1, ..., y) N+M )

[0178] Calculate the density D of the thermogram ij :

[0179]

[0180] Where, x N+M and y N+M is the horizontal and vertical coordinates of the object to be protected; COG(ij) is the number of protected objects contained in the grid cell of the i-th row and j-th column. The spatial distribution range is divided into several grid cells, each grid cell is Δx×Δy in size, and each grid cell is assigned a color value to generate a graphic.

[0181] Based on this preliminary map, the system generates a cloud-shaped "machine chain" network planar diagram (or, in other words, the cloud-shaped "machine chain" network planar diagram is a replica and enlargement of the preliminary diagram, because the area of ​​the cloud-shaped "machine chain" network is slightly larger than the distribution range of the objects to be protected). First, a planar coordinate system is established with the center point of the cloud-shaped "machine chain" network planar diagram as the origin. Then, based on this planar coordinate system, a new two-axis system is established to form a three-dimensional coordinate system. In this way, a three-dimensional coordinate system for the UAV (base station) layout is obtained.

[0182] When the distribution of personnel and equipment of the target group changes, the shape of the cloud-like "machine chain" network also needs to change accordingly. At this time, the system will regenerate a new approximate distribution map based on the changes in the personnel and equipment of the target group. Based on this new approximate distribution map, a new cloud-like "machine chain" plane enclosure will be generated. Similar to the above steps, the system first establishes a new planar coordinate system with the center point of this newly generated plane enclosure as the origin. Then, based on this new planar coordinate system, a new Z-axis will be created to form a new three-dimensional coordinate system, thus obtaining a new three-dimensional coordinate system for the UAV (base station) layout.

[0183] At this time, all unmanned aerial vehicles (base stations) can be repositioned according to the coordinate values of the unmanned aerial vehicles (base stations) in the new three-dimensional coordinate system, and the repositioning can be performed, so that all unmanned aerial vehicles (base stations) can find appropriate positions according to the coordinate values of the new positions. In this way, the shape of the entire cloud-shaped "machine chain" network changes accordingly, and matches the distribution changes of the personnel and equipment to be protected.

[0184] The application also provides an unmanned aerial vehicle-based mobile network construction system based on the method.

[0185] The unmanned aerial vehicle has the function of adjusting its flight state in real time, and realizes intercommunication and interconnection between unmanned aerial vehicles through wireless broadband ad hoc network technology.

[0186] The intelligent unmanned aerial vehicle has the ability of intelligent perception of threats, automatic avoidance of attacks, and autonomous retreat from the battlefield, etc. For example, when encountering enemy physical attacks, the intelligent unmanned aerial vehicle can quickly perceive the potential threat direction, height and speed with the help of sensors, and automatically avoid according to its own operating state. When encountering strong interference or electromagnetic signals that can damage its electronic components, it can perceive in advance according to the feedback signal and autonomously avoid a certain area.

[0187] With the help of control software, the unmanned aerial vehicle changes its cruising trajectory and radius in a preprogrammed manner, so as to reduce the probability of physical damage caused by fixed trajectory flight.

[0188] The base station is arranged on the unmanned aerial vehicle and is used for continuously transmitting and receiving network signals to a certain area, and is a key node for data transmission of the entire mobile network. The base station should be integrated with intelligent technology, so that the "machine chain" base station has strong intelligence, such as self-adaptive power adjustment.

[0189] The ground control station is divided into fixed stations and mobile stations. The fixed station is arranged at a fixed point, and the mobile station is arranged at a mobile point. The ground control station is connected with the base station, and is responsible for classifying and grouping intelligent unmanned aerial vehicles, planning operation routes, adjusting attitudes, controlling speeds, and deploying the number of unmanned aerial vehicles of different types (states).

[0190] The "machine chain" terminal includes fixed "machine chain" terminals and mobile "machine chain" terminals. The mobile "machine chain" terminal is used to realize uninterrupted network connection with the base station, and is suitable for mobile platforms such as aircraft, ships and vehicles.

[0191] The user terminal includes various application software systems and various devices supporting the operation of the software systems. The application software system meets the task requirements of different tasks and different professional teams.

[0192] In one preferred embodiment of the present application, the ground control station comprises a control platform, a control antenna, a gateway station and a data antenna.

[0193] The control platform is used for classifying and grouping UAVs, planning a running route, adjusting an attitude, regulating a speed, deploying a number of UAVs of different classes, the control antenna is in communication with the control antenna of a UAV, the UAV is linked to the ground control station, and the transmission of an adjustment control signal is completed.

[0194] The gateway station is used for connecting a base station to a wired network, realizing the access and control of the wired network, the data antenna is in communication with the base station, the wired network is linked to the base station, and the transmission of an adjustment control signal is completed.

[0195] Preferably, the control platform of the ground control station is installed with a "UAV (base station) working condition acquisition module". Each UAV and the base station carried thereon is installed with a set of performance parameter acquisition device (i.e. sensor), each acquisition device establishes a special (strip) link with the ground control platform, and real-time feedback of relevant parameters of the UAV and the base station carried thereon is realized. For the UAV, an electric quantity information acquisition device, a speed information acquisition device, a height information acquisition device and an internal control board circuit working condition information acquisition device are installed, and real-time feedback of UAV condition information is realized. For the base station, an electric quantity information acquisition device, a transmitting power information acquisition device, a receiving power information acquisition device and an internal main circuit working condition information acquisition device are installed, and all the acquisition devices are collected together to form the running working condition information (similar to the vital sign information of a human body) of the UAV and the base station carried thereon. When a fault occurs in a certain UAV or base station, the above relevant information can be displayed to further determine which UAV or base station is abnormal and whether it will affect the normal operation of the entire network system. Accordingly, it can be determined which UAV or base station needs to be replaced.

[0196] More preferably, the control platform of the ground control station is installed with a "UAV (base station) distribution module". According to the area of the cloud-like "machine chain" network, the shape (in the form of a strip or cloud cluster) of the cloud-like "machine chain" network and the number of UAVs (base stations), a UAV (base station) layout diagram (similar to a network node topology diagram) is automatically generated; a three-dimensional coordinate system of the UAV (base station) layout is established with the center point of the layout as the origin, and a coordinate value (X, Y, Z) is obtained at any point in the coordinate system. On this basis, all the UAVs (base stations) are numbered and distributed to the coordinate system. In this way, whether an online running UAV (base station) or a standby UAV (base station) will be distributed to the coordinate system and assigned a three-dimensional coordinate value. Although the three UAVs are on the ground, they will also be pre-distributed to the same layout coordinate system, and each three UAV will also be assigned a coordinate value.

[0197] In a preferred scheme of the present application, the "machine chain" terminal comprises an antenna and a router, and the total power is about 50-100 watts. The antenna adopts a portable support, has a 6-level dustproof and 1-level waterproof performance, can work in water, and has a mass of about 1.0-2.0 kg, and is used to realize networking with the base station in air operation.

[0198] The router is provided with multiple frequency bands (such as 2.4G Rz, 5G Wz, 6 GHz, etc.), adopts a WiFi 6 technology standard, is provided with multiple gigabit network interfaces, supports 50-100 user terminal devices at the same time, has a speed of not less than 200 Mbgs at a distance of 5-10 meters, has a maximum coverage area of not less than 100-200 square meters, has a 5-level dustproof and 6-level waterproof performance, and is used to realize connection with the user terminal.

[0199] In the present application, N intelligent unmanned aerial vehicles flying in the air carry "machine chain" base stations, form an air cloud-shaped base station, realize autonomous, intelligent and safe flight by means of intelligent unmanned aerial vehicle technology, and realize intercommunication and interconnection between unmanned aerial vehicles by means of wireless broadband tactical ad hoc network technology.

[0200] N "machine chain" terminals fixed or moved on the ground form a local point-shaped information transmission intermediate node, N user terminals arranged at any point serve as an information transmission end node, a local network based on Wi-Fi is constructed by means of the sixth generation wireless network, and information intercommunication and interconnection are realized.

[0201] N ground control stations are arranged (deployed) in a command post, and the intelligent unmanned aerial vehicle system is autonomously, orderly, safely and reliably operated by means of a control platform as required, and orderly access to a wired communication network is realized by means of a gateway station.

[0202] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0203] Although the embodiments of the present application have been shown and described, those skilled in the art can understand that various changes, modifications, replacements and variations can be made to the embodiments without departing from the principles and purposes of the present application, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. A method for constructing a mobile network based on a UAV, characterized in that, It comprises the following steps: According to the performance parameters of the unmanned aerial vehicle, the flight trajectory of the single unmanned aerial vehicle is planned and set in advance, so that it can move in a spherical or elliptical trajectory within the preset space range; According to the network demand range, the required cloud-shaped "machine chain" network area and the number of unmanned aerial vehicle base stations required in the "machine chain" are calculated; According to the form and route of the network demand side, the shape, moving direction and speed of the cloud-shaped "machine chain" network are planned as a whole; The unmanned aerial vehicles are divided into categories and states, the number of unmanned aerial vehicles of different categories is determined, the communication base station is carried on the unmanned aerial vehicles of different categories, and the mobile network is constructed; According to the form and route of the network demand side, the shape, moving direction and speed of the cloud-shaped "machine chain" network are planned as a whole, and the specific steps are as follows: When the network demand side advances along one or more columns, the cloud-shaped "machine chain" network shape should take the middle point of the network demand side as the reference point, extend forward and backward, and present in a strip shape, consistent with the column; When the network demand side advances in a group, the cloud-shaped "machine chain" network should take the center point of the group as the center, and present in a cloud shape; Set the group center point Is: ， wherein, Ctis the coordinate of the center point at time t. Shape of the "cloud" of machine links represents a circle with center at and radius . ， wherein, is dynamically adjusted according to changes in group size, travel speed, and network demand: ， wherein, is the group size, i.e., the number of users or group size at time t; denotes the travel speed of the group, i.e., the moving speed of the group at time t; denotes the network demand, i.e., the network bandwidth demand at time t; , , is the corresponding weight coefficient, reflecting the relative importance of each factor to ; is a decay factor, used to simulate the influence of time on the group size, speed, and demand. As time goes by, the network demand can change, and the decay factor is used to adjust this change. The moving direction of the cloud-shaped "machine chain" network is consistent with the direction and speed of the network demand side, and the direction of the network demand side is obtained in real time by means of geographic information system; The unmanned aerial vehicles keep spherical or elliptical flight trajectory and move forward synchronously with the moving direction of the network demand side; All unmanned aerial vehicles of the cloud-shaped "machine chain" move synchronously and integrally; The network demand side obtains the speed information of the network demand side in real time; When the speed of the network demand side changes, the control terminal changes and controls the moving speed of the cloud-shaped "machine chain" network, so that it changes synchronously with the speed of the network demand side. 2.The UAV-based mobile network construction method of claim 1, wherein, The method for calculating the required cloud-shaped "machine chain" network area according to the network demand range is: S=A*B, Wherein, S is the area of the cloud-shaped "machine chain" network, A is the area of the security region, and B is the terrain environment adjustment coefficient. 3.The UAV-based mobile network construction method of claim 2, wherein, The number of unmanned aerial vehicle base stations required in the "machine chain" is: ， Wherein, b is the number of unmanned aerial vehicle base stations required in the "machine chain", T is the coincidence degree adjustment coefficient, K is the effective coverage area of a single "machine chain" base station; A is the area of the security region, B is the terrain environment adjustment coefficient, E is the environment correction coefficient, and L is the network load adjustment coefficient. 4.The UAV-based mobile network construction method of claim 3, wherein, The unmanned aerial vehicles are divided into: One-bit machine, corresponding to online state; Two-bit machine, corresponding to quasi-online state; Three-bit machine, corresponding to standby state; The number of one-bit machines is R1, which is the number of base stations b of the cloud-shaped "machine chain" network; The number of two-bit machines is R2, which is less than the number of one-bit machines, and is: R2=R1*P1, Wherein, R2 is the number of two-bit machines, R1 is the number of one-bit machines, and P1 is the two-bit machine number adjustment system; The number of three-bit machines is R3, which is less than the number of two-bit machines, and is: R3=R2*P2, Wherein, R3 is the number of three-bit machines, R2 is the number of two-bit machines, and P2 is the three-bit machine number adjustment coefficient; The automatic replacement method is adopted to realize the function connection of the damaged unmanned aerial vehicle, that is, the two-bit machine is changed into the one-bit machine to participate in the network connection. 5.The UAV-based mobile network construction method of claim 4, wherein, The automatic replacement method is: Let each node state in the UAV network be , i = 1, 2, …, N, each node can be in one of two states: ； ； Let the topology matrix of the UAV network be T1, where each element represents the connectivity from node i to node j, 1 represents connectivity, and 0 represents no connectivity; when a fault occurs, the topology needs to be adjusted to be: ， wherein, represents the node state vector that needs to be adjusted after the failure is sent, is the adjusted topology matrix; Based on the reliability and power consumption of the node, the node with the highest score is selected for replacement: ， wherein, 1 and 1 is a weight factor, and respectively represent the reliability and the remaining power of node j, the score of the j nodes. 6.The UAV-based mobile network construction method of claim 1, wherein, The method for constructing a mobile network by using the determined unmanned aerial vehicles of different categories carrying communication base stations is specifically as follows: When the cloud-shaped "machine chain" network moves and encounters aerial objects or other foreign objects, the sensor senses the position, height and speed information of the surrounding aerial objects or other foreign objects, and according to the position, height and speed of the unmanned aerial vehicle, the unmanned aerial vehicle performs automatic obstacle avoidance and automatic obstacle circumvention protection actions accordingly. The unmanned aerial vehicle has a self-sensing function of interference signals, and adjusts the transmission frequency according to the strength of the interference signals. When the interference signal is strong, the transmission frequency is increased accordingly. 7.The UAV-based mobile network construction method of claim 1, wherein, According to the distribution of the personnel and equipment of the object to be protected, a sketch map based on the distribution range of the object to be protected is generated, specifically as follows: The position information of the object to be protected is collected, including the position coordinates of each object. The spatial distribution range of the object to be protected is determined through the extreme points MinX, MaxX, MinY and MaxY. MinX = min( ), MaxX = max( ), MinY = min( ), MaxY = max( ), Computing a heat map density : ， wherein, and are the horizontal and vertical coordinates of the object to be protected; is the number of objects to be protected contained in the grid cell in the i-th row and j-th column, the spatial distribution range is divided into a plurality of grid cells, and the size of each grid cell is a color value is assigned to each network cell, and a graph is generated; Based on the sketch map, a cloud-shaped "machine chain" network plane is generated. First, the center point of the cloud-shaped "machine chain" network plane is taken as the origin to establish a plane coordinate system, and then a three-dimensional coordinate system is formed based on the plane coordinate system to obtain a three-dimensional coordinate system of the unmanned aerial vehicle base station layout. When the distribution of the personnel and equipment of the object to be protected changes, a new sketch map based on the new distribution range of the changed object to be protected is generated according to the change of the personnel and equipment of the object to be protected, and a new cloud-shaped "machine chain" network plane is generated based on the new sketch map. A new plane coordinate system is established with the center point of the newly generated plane as the origin, and then a new z-axis is established based on the new plane coordinate system to form a new three-dimensional coordinate system, thereby obtaining a new three-dimensional coordinate system of the unmanned aerial vehicle base station layout. According to the coordinate values of the unmanned aerial vehicle base station in the new three-dimensional coordinate system, all the unmanned aerial vehicle base stations can be repositioned, and the "repositioning" is executed. All the unmanned aerial vehicle base stations will find appropriate positions according to the coordinate values of the new positions to match the change of the distribution of the personnel and equipment of the object to be protected.

8. A UAV-based mobile network building system based on the method of any one of claims 1-7, characterized in that, The system includes unmanned aerial vehicles, base stations, ground control stations, "machine chain" terminals and user terminals. The unmanned aerial vehicles have a function of adjusting their flight states in real time, and realize intercommunication and interconnection between the unmanned aerial vehicles through wireless broadband self-organizing network technology. The base stations are arranged on the unmanned aerial vehicles and are used for continuously transmitting and receiving network signals to a certain area. The ground control stations include fixed stations and mobile stations. The fixed stations are arranged at fixed points, and the mobile stations are arranged at mobile points. The ground control stations are connected with the base stations. The "machine chain" terminals include fixed "machine chain" terminals and mobile "machine chain" terminals. The mobile "machine chain" terminals are used for realizing uninterrupted network connection with the base stations. The user terminals include various application software systems and various devices supporting the operation of the software systems. The application software systems meet the requirements of different tasks and different professional teams for performing tasks. 9.The UAV-based mobile network construction system of claim 8, wherein, The ground control stations include control platforms, control antennas, gateway stations and data antennas. The control platform is used for classifying and grouping UAVs, planning a running route, adjusting a posture, regulating a speed, adjusting the number of different types of UAVs, controlling the communication between an antenna and a control antenna of a UAV, realizing the linkage between the UAV and a ground control station, and completing the transmission of an adjustment control signal. The gateway station is used for connecting a base station and a wired network, realizing the access and control of the wired network. The data antenna communicates with the base station, realizing the linkage between the wired network and the base station.

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