A multi-station unmanned aerial vehicle identification and positioning system and an identification and positioning method

Abstract

This invention relates to a multi-station UAV identification and positioning system and method, belonging to the field of UAV countermeasures. The purpose of this invention is to solve the problems of existing technologies, such as reliance on protocol parsing, poor adaptability, rigid antenna array requirements, and high demands on antenna shape and layout. The multi-station UAV identification and positioning system includes: a master controller, controlled devices, a radio transceiver platform, antenna components, and a cloud server. The master controller communicates with the cloud server via a network port to upload data. The master controller communicates with several controlled devices (two or more) via a wireless local area network. The master controller and controlled devices communicate with their respective subordinate radio transceiver platforms via network ports, with each radio transceiver platform corresponding to one master controller or controlled device.

Description

Technical Field

[0001] This invention belongs to the field of drone countermeasures, and relates to a multi-station drone identification and positioning system and identification and positioning method. Background Technology

[0002] With the popularization of the "low-altitude economy" and the rapid development of related technologies, civilian drones have become ubiquitous in daily life and production. However, regulatory rules and measures related to drones are still lacking to some extent, and incidents of "abuse" and "unauthorized flights" occur frequently, seriously endangering the safety of people's normal production and life, and hindering the healthy and sustainable development of the drone industry. Effective identification methods are urgently needed to warn of and respond to potential low-altitude threats.

[0003] Unmanned aerial vehicle (UAV) radio identification and positioning systems typically combine both UAV identification and positioning. Existing technologies rely on UAV protocol parsing for identification, requiring manual addition of protocol types to the database as UAV models iterate, resulting in poor adaptability. Furthermore, existing technologies usually use location-based methods, necessitating antenna arrays and placing high demands on the shape and layout of the antennas. Summary of the Invention

[0004] The purpose of this invention is to solve the problems of existing technologies that rely on protocol parsing, have poor adaptability, require antenna arrays, and have high requirements for antenna shape and layout. Therefore, this invention proposes a multi-station UAV identification and positioning system and identification and positioning method.

[0005] A multi-station UAV identification and positioning system includes: a main controller, a controlled device, a radio transceiver platform, an antenna assembly, and a cloud server;

[0006] The main control unit communicates with the cloud server via the network port to upload data;

[0007] The main control unit communicates with several controlled units via a wireless local area network, wherein the number of several units is greater than or equal to two.

[0008] The master controller and the controlled machine communicate with their respective subordinate radio transceiver platforms through network ports, with one radio transceiver platform corresponding to one master controller or one controlled machine.

[0009] The main control unit is used to issue drone target recognition commands, determine whether the drone in the recognition result is a registered drone, and if so, continue to issue drone target recognition commands; otherwise, issue drone positioning and sampling commands.

[0010] The main controller is used to receive positioning sampling results from the controlled device, determine whether there is a UAV signal segment in the results, and if so, continue to issue UAV positioning calculation instructions; otherwise, return to the recognition state and issue UAV target recognition instructions.

[0011] The main controller is used to forward the data segments for processing intercepted from the subordinate radio transceiver platform;

[0012] The main controller is used to receive time difference results from the controlled machine, perform multi-station positioning calculation based on arrival time difference, and upload the calculation results to the cloud server.

[0013] The controlled device is used to forward the UAV target identification command from the master controller to the subordinate radio transceiver platform and to forward the identification results from the subordinate radio transceiver platform to the master controller;

[0014] The controlled device is used to forward the UAV positioning and sampling commands from the master controller to the subordinate radio transceiver platform and to forward the positioning and sampling results from the subordinate radio transceiver platform to the master controller.

[0015] The controlled machine is used to forward the UAV positioning and calculation instructions from the master controller to the subordinate radio transceiver platform and to receive the calculation data segments from the subordinate radio transceiver platform.

[0016] The controlled machine is used to receive the calculation data segment forwarded by the master controller, perform dual-station time difference calculation locally, and transmit the time difference result to the master controller;

[0017] The radio transceiver platform is used to receive UAV target identification instructions issued by the corresponding master controller or forwarded by the corresponding controlled machine, perform UAV target identification on the radio signals received by the antenna assembly, and transmit the identification results back to the corresponding master controller or controlled machine.

[0018] The radio transceiver platform is used to receive UAV positioning and sampling instructions issued by the corresponding master controller or forwarded by the corresponding controlled machine, perform UAV positioning and sampling on the radio signals received by the antenna assembly, and transmit the UAV positioning and sampling results back to the corresponding master controller or controlled machine.

[0019] The radio transceiver platform is used to receive UAV positioning and calculation instructions issued by the corresponding master controller or forwarded by the corresponding controlled machine, extract locally cached UAV signal data through the index contained in the instruction to form a calculation data segment, and transmit the calculation data segment back to the corresponding master controller or controlled machine.

[0020] The antenna assembly is used to receive various radio signals, and its quantity is consistent with that of the radio transceiver platform.

[0021] The cloud server is used to record various work logs.

[0022] The specific process of a multi-station UAV identification and positioning method is as follows:

[0023] Step 1: The master controller communicates directly with the corresponding radio transceiver platform via the network port. The master controller also communicates with the controlled devices via a wireless LAN. The controlled devices communicate with their respective subordinate radio transceiver platforms via the network port. The master controller issues a UAV identification command. The radio transceiver platforms under the master controller and the controlled devices receive the UAV target identification command issued by the master controller or forwarded by the controlled devices. Each radio transceiver platform performs UAV target identification on the radio signals received by its corresponding antenna assembly to obtain the UAV's frequency. and drone latency value information;

[0024] Step 2: The main controller determines the drone's latency value. If the drone belongs to a whitelist member, and if so, determine that it is a known drone and proceed to step one to continue drone target identification; otherwise, the drone is a suspicious drone, and the drone frequency will be... and drone latency value The information is encapsulated into UAV positioning and sampling instructions; proceed to step three.

[0025] Step 3: The master controller issues a drone positioning and sampling command. The radio transceiver platforms under the master controller and the controlled drone receive the drone positioning and sampling command issued by the master controller or forwarded by the controlled drone, and perform drone positioning sampling on the radio signals received by their respective antenna components; after sampling is completed, a sequence is obtained. ;

[0026] The radio transceiver platform will obtain the sequence Send the data to the corresponding master or slave machine via the network port;

[0027] The controlled unit receives sequences transmitted by subordinate radio transceiver platforms. The controlled machine will sequence Forwarded to the main control unit;

[0028] The main controller receives sequences transmitted by subordinate radio transceiver platforms. The master controller receives the sequence forwarded by the controlled machine. ;

[0029] The main controller uses a time-stamp matching algorithm to calculate the most likely signal segment of the drone signal. If no most likely signal segment exists, it is judged as a false trigger, and step one is repeated; if the most likely signal segment exists, it is marked as such. Continue with step four;

[0030] Step 4: The radio transceiver platform receives the UAV positioning calculation instructions issued by the corresponding master controller or forwarded by the corresponding controlled machine, transmits the corresponding radio signal sampling data to the corresponding master controller or controlled machine, completes the UAV positioning calculation locally on the controlled machine and master controller, uploads the UAV location to the cloud server, and the master controller re-executes Step 1.

[0031] Preferably, in step one, the master controller communicates directly with the corresponding radio transceiver platform via a network port, and communicates with the controlled machine via a wireless local area network. The controlled machine communicates with its respective subordinate radio transceiver platforms via a network port. The master controller issues a UAV identification command, and the radio transceiver platforms subordinate to the master controller and the controlled machine receive the UAV target identification command issued by the master controller or forwarded by the controlled machine. Each radio transceiver platform performs UAV target identification on the radio signals received by its corresponding antenna assembly to obtain the UAV frequency. and drone latency value Information; the specific process is as follows:

[0032] The main controller issues drone target identification commands to subordinate radio transceiver platforms, and the main controller issues drone target identification commands to all controlled drones.

[0033] The controlled device receives the UAV identification command issued by the master controller, enters the waiting state for identification results, and forwards the UAV target identification command to the subordinate radio transceiver platform;

[0034] The radio transceiver platform receives UAV target identification commands issued by the master controller or forwarded by the controlled machine through the network port;

[0035] The radio transceiver platform acquires radio signals by continuously scanning frequencies in the 2.4 GHz to 2.5 GHz and 5.7 GHz to 5.85 GHz ranges simultaneously using an antenna assembly.

[0036] Set the relevant spectral threshold Set the time-width threshold Set a list of delay values. ;

[0037] The radio transceiver platform performs time-delay autocorrelation processing on the radio signals obtained from frequency sweeping to obtain the autocorrelation spectrum. The delay parameter iterates through the set delay value list and is based on the set correlation spectrum threshold. and time-width threshold Obtain drone frequency and drone latency value information;

[0038] The main controller or controlled unit receives the UAV frequency points transmitted by the subordinate radio transceiver platform. and drone latency value Information; the controlled aircraft forwards the UAV frequency to the main controller. and drone latency value information.

[0039] Preferably, the radio transceiver platform performs time-delay autocorrelation processing on the radio signal obtained by frequency sweeping to obtain an autocorrelation spectrum. The time delay parameter iterates through a list of set time delay values ​​and is based on a set correlation spectrum threshold. and time-width threshold Obtain drone frequency and drone latency value Information; the specific process is as follows:

[0040] 1) Initialize a single frequency band as ;

[0041] 2) Assume the radio signal in the frequency band is Select delay value ;

[0042] in A list of delay values ​​to be set;

[0043] The delayed autocorrelation processing method is as follows:

[0044]

[0045] in, The discrete autocorrelation spectrum results are obtained by downsampling at 1 / W octave. For complex discrete radio signals, for conjugate, The selected drone delay value, To handle the long sliding window, |·| represents the cumulative offset in a single summation calculation, and |·| represents the modulo calculation. The discrete time point is the result of downsampling the original discrete signal by a factor of 1 / W, where k is an integer multiple. , In order to make Any natural number that satisfies the restrictions. The original signal length;

[0046] Based on the frequency band and delay value of the radio transceiver platform Searching for the corresponding autocorrelation results arrive All spectral peaks within the range are greater than the relevant spectral threshold. Autocorrelation spectrum peak ;

[0047] If it exists, then the corresponding UAV frequency will be used. and drone latency value Send the data to the corresponding master or slave machine via the network port;

[0048] If it does not exist, the frequency band remains unchanged, and the calculation is performed. Find the next delay value. arrive All spectral peaks within the range are greater than the relevant spectral threshold. Autocorrelation spectrum peak If it exists, then the corresponding UAV frequency will be used. The drone latency value is sent to the corresponding master or slave device via the network port; if it does not exist, the frequency band remains unchanged, and the calculation is performed. Find the next delay value. arrive All spectral peaks within the range are greater than the relevant spectral threshold. Autocorrelation spectrum peak ;

[0049] Until the traversal is complete All delay values ​​in the middle;

[0050] express arrive The autocorrelation spectrum;

[0051] 3) Determine whether the set spectrum range has been traversed completely;

[0052] If so, obtain the drone frequency points and drone latency information for all frequency bands;

[0053] If not, jump to the next frequency band and repeat step 2) until the set frequency range has been traversed.

[0054] Preferably, in step three, the master controller issues a UAV positioning and sampling command, and the radio transceiver platforms under the master controller and the controlled UAV receive the UAV positioning and sampling command issued by the master controller or forwarded by the controlled UAV, and perform UAV positioning sampling on the radio signals received by their respective antenna components; after sampling is completed, a sequence is obtained. ;

[0055] The radio transceiver platform will obtain the sequence Send the data to the corresponding master or slave machine via the network port;

[0056] The controlled unit receives sequences transmitted by subordinate radio transceiver platforms. The controlled machine will sequence Forwarded to the main control unit;

[0057] The main controller receives sequences transmitted by subordinate radio transceiver platforms. The master controller receives the sequence forwarded by the controlled machine. ;

[0058] The main controller uses a time-stamp matching algorithm to calculate the most likely signal segment of the drone signal. If no most likely signal segment exists, it is judged as a false trigger, and step one is repeated; if the most likely signal segment exists, it is marked as such. If so, proceed to step four;

[0059] The specific process is as follows:

[0060] Step 3: The main controller sends the UAV positioning command to the subordinate radio transceiver platform, and sends the UAV positioning sampling command to all controlled devices.

[0061] The controlled device receives the UAV positioning command issued by the master controller, saves the parameters in the command, enters the waiting positioning calculation state, and forwards the UAV positioning sampling command to the subordinate radio transceiver platform.

[0062] The parameter in the instruction is the synchronous sampling time. Drone frequency Target delay value and gain settings ;

[0063] The radio transceiver platform receives UAV positioning and sampling commands issued by the corresponding master controller or forwarded by the corresponding slave controller, and sets the sampling frequency point according to the command content. and synchronous sampling time ;

[0064] The radio transceiver platform achieves local time synchronization through a time synchronization module, at the start of the synchronization sampling time. All radio transceiver platforms started simultaneously via antenna assemblies. Sampling of UAV radio signals at specific frequencies;

[0065] Step 3.2: After sampling is completed, each radio transceiver platform obtains radio signal sampling data. The target delay value provided by the positioning sampling command is cached locally and used locally. Delayed autocorrelation preprocessing is performed to obtain autocorrelation results, and then the autocorrelation results are searched for... arrive All spectral peaks within the range are greater than the relevant spectral threshold. Autocorrelation spectrum peak of Let it be the starting index subscript. ;

[0066] express arrive The peak value of the autocorrelation spectrum; This indicates that the conditions for obtaining the value are met. , The discretized time point is the original discrete signal after being downsampled by a factor of 1 / W. Indicates the time-width threshold;

[0067] Based on all index subscripts Composition sequence ;

[0068] The radio transceiver platform will obtain the sequence Send the data to the corresponding master or slave machine via the network port;

[0069] The controlled unit receives sequences transmitted by subordinate radio transceiver platforms. The controlled machine will sequence Forwarded to the main control unit;

[0070] The main controller receives sequences transmitted by subordinate radio transceiver platforms. The master controller receives the sequence forwarded by the controlled machine. ;

[0071] The main controller uses a time-stamp matching algorithm to calculate whether the drone signal contains the most likely signal segment. If no most likely signal segment exists, it is determined to be a false trigger, and step one is repeated. If the most likely signal segment exists, its starting index is marked as [index missing]. If so, proceed to step four.

[0072] Preferably, the main controller uses a time-stamp matching algorithm to calculate whether the UAV signal contains the most likely signal segment. If no most likely signal segment exists, it is determined to be a false trigger, and step one is re-executed. If a most likely signal segment exists, the starting index of the most likely signal segment is marked as... The specific process is as follows:

[0073] 1): Set the matching window length ;

[0074] 2): Find all sequences Maximum index value in ;

[0075] 3): Order ;

[0076] 4): When each sequence All of them exist in The index in the range marks the current position. For index ;

[0077] 5), let Repeat step 4) until... To obtain the starting index of the most likely signal segment. ;

[0078] If the traversal ends and no matching condition is found... This segment is determined to be the most likely to be nonexistent.

[0079] Preferably, in step four, the radio transceiver platform receives the UAV positioning calculation command issued by the corresponding master controller or forwarded by the corresponding controlled device, transmits the corresponding radio signal sampling data to the corresponding master controller or controlled device, completes the UAV positioning calculation locally on the controlled device and master controller, uploads the UAV location to the cloud server, and the master controller re-executes step one; the specific process is as follows:

[0080] The main controller will use the starting index of the most likely signal segment. The commands are packaged into UAV positioning and calculation instructions. The main controller sends the UAV positioning and calculation instructions to the subordinate radio transceiver platforms and to all controlled UAVs.

[0081] The controlled device receives the UAV positioning and calculation instructions from the master controller, and then forwards the UAV positioning and calculation instructions to its subordinate radio transceiver platform.

[0082] The radio transceiver platform receives UAV positioning and calculation commands from the corresponding master controller or the corresponding controlled device, and determines the location based on the starting index of the most likely signal segment. Extract the corresponding fixed length from the local cache Radio signal sampling data ;

[0083] for Extract from the middle Starting from, A signal segment of length 1;

[0084] The radio transceiver platform will intercept the data. Transmitted to the corresponding master or slave unit;

[0085] The main control unit receives intercepted data transmitted from the subordinate radio transceiver platform. Then, it is forwarded to each controlled machine;

[0086] After receiving intercepted data transmitted from subordinate radio transceiver platforms and intercepted data forwarded by the master controller, the controlled unit performs bi-station time difference calculation locally using a matched filtering algorithm to obtain the time difference result. ;

[0087] The controlled machine will display the time difference results. Transmitted to the main control unit;

[0088] The master controller receives the time difference results transmitted by all the controlled machines. Then, the local machine combines the location information of each station to perform positioning calculation based on the time difference of arrival, calculates the drone's location, and uploads the drone's location to the cloud server. The main control unit then re-executes step one.

[0089] Preferably, the time difference calculation for the two stations is performed using a matched filtering algorithm to obtain the time difference result. The specific process is as follows:

[0090] Assuming the intercepted data forwarded from the main control unit is The intercepted data obtained directly by the controlled machine from the subordinate radio transceiver platform is ;

[0091] 1) and All are converted to the frequency domain using Fourier transform, and the calculation method is as follows:

[0092]

[0093]

[0094] in, for Frequency domain signal after Fourier transform; for Frequency domain signal after Fourier transform; Fourier transform;

[0095] 2) and Performing a matched filter operation in the frequency domain and converting back to the time domain, the calculation method is as follows:

[0096]

[0097] in, for Conjugate; This is the inverse Fourier transform; The result of the matched filtering;

[0098] 3) In Find the index of the largest spectral peak The time difference result is obtained after coordinate mapping. The coordinate mapping method is as follows:

[0099] .

[0100] Preferably, the master controller receives the time difference results transmitted by all controlled machines. Then, the location of the drone is calculated locally based on the time difference of arrival by combining the location information of each station; the specific process is as follows:

[0101] 1) The calculated time differences between the master control station and the three controlled stations are as follows: , , ,based on , , Obtain the time difference vector ;

[0102] 2) The main control unit obtains and caches the coordinates of the main control unit station in the geodetic coordinate system through the time synchronization module. ;

[0103] The master controller and the controlled machine communicate periodically to obtain and cache the coordinates of the controlled machine's station in the geodetic coordinate system. The coordinates of the controlled machine 2 station in the geodetic coordinate system The coordinates of the three controlled stations in the geodetic coordinate system ;

[0104] 3) Set the coordinates of the main control station in the geodetic coordinate system. Convert to Cartesian coordinate system ;

[0105] The coordinates of the controlled machine 1 station in the geodetic coordinate system Convert to Cartesian coordinate system ;

[0106] The coordinates of the controlled machine 2 station in the geodetic coordinate system Convert to Cartesian coordinate system ;

[0107] The coordinates of the three controlled machine stations in the geodetic coordinate system Convert to Cartesian coordinate system ;

[0108] 4) Based on and the speed of light get , ;

[0109] based on and the speed of light get , ;

[0110] based on and the speed of light get , ;

[0111] based on , , To obtain the distance difference vector ;

[0112] in, This is the difference between the distance from the drone to the controlled station 1 and the distance from the drone to the master control station. This is the difference between the distance from the drone to the controlled station 2 and the distance from the drone to the main control station. This is the difference between the distance from the UAV to the controlled station 3 and the distance from the UAV to the main control station;

[0113] 5) Assume the target position coordinates of the UAV in the rectangular coordinate system are: The distance from the target to the main control unit is Establish a system of equations:

[0114]

[0115] in, The square of the norm;

[0116] The target position of the UAV in the rectangular coordinate system is obtained by solving the system of equations using the least squares method. ;

[0117] 6) Convert the UAV target position from the Cartesian coordinate system to the geodetic coordinate system. ;

[0118] The main controller will display the target position of the UAV in the geodetic coordinate system. Uploaded to the cloud server, the main control unit re-executes step one.

[0119] Preferably, there is timed message communication between the master controller and the controlled machine;

[0120] When the controlled machine comes online, it automatically establishes a message communication connection with the main control machine through the wireless self-organizing network module.

[0121] The message communication includes the controlled machine sending its online status identifier and local location information to the master machine, and the master machine sending confirmation information to the controlled machine.

[0122] The cloud server interacts with the main control computer via a network port.

[0123] The cloud server has a built-in offline map. By acquiring data from the main controller, the cloud server displays the location information of the main controller and the controlled device in real time, and displays the location information of the drone when it is located.

[0124] The beneficial effects of this invention are as follows:

[0125] Compared to existing drone identification and positioning devices, this invention is based on signal processing algorithms and does not rely on the parsing of drone data protocols, thus possessing the ability to identify unknown drones. This invention uses a positioning method based on time difference of arrival, requiring only a small number of modular antenna components. The components are highly replaceable, and the layout requirements are flexible. Furthermore, this invention has strong scalability, enabling rapid access to new sites via wireless LAN, and exhibits strong adaptability.

[0126] This invention proposes a multi-station UAV identification and positioning system and method, which can achieve wide-range frequency sweeping across multiple frequency bands from 80MHz to 6.0GHz. It processes UAV signals based on a time-delay autocorrelation algorithm to identify known and unknown UAVs. It uses an algorithm based on time difference of arrival for multi-station positioning of UAVs, which can flexibly adjust the station deployment. Moreover, the components are modular and can be quickly expanded through the network, which has strong engineering application value. This invention only requires multiple single antenna components (multiple single antennas) and does not require the more expensive multi-antenna array (one integrated array component). There are no requirements for antenna shape and layout.

[0127] This invention is based on a radio transceiver platform, which can customize the frequency sweep range and adopts a multi-station positioning method based on time difference of arrival. It can automatically obtain the station address through the built-in time synchronization module, and realize the flexible deployment of stations according to the environment.

[0128] This invention analyzes the radio signals obtained by frequency sweeping using a time-delay autocorrelation algorithm, and is compatible with various types of UAV targets, including older and newer UAVs, thus meeting the versatility requirements for UAV detection.

[0129] This invention can interact with a cloud server via a network port. Users can remotely view the system's operation logs through the cloud server and view the drone detection results and their location markers in real time via an offline map. Attached Figure Description

[0130] Figure 1 This is a schematic diagram of the component structure of the present invention;

[0131] Figure 2 This is a network topology diagram of the present invention;

[0132] Figure 3 Time-frequency graph of drone signal captured at 5.8 GHz;

[0133] Figure 4 This is a diagram illustrating an example of delayed autocorrelation processing. , , , To handle the length of the sliding window;

[0134] Figure 5 Example diagram of a drone positioning and sampling command message. , , , ;

[0135] Figure 6 This is an example diagram of delayed autocorrelation preprocessing. , ;

[0136] Figure 7 This is a flowchart of the process of the present invention. Detailed Implementation

[0137] Specific Implementation Method 1: This implementation method provides a multi-station UAV identification and positioning system, comprising: a main controller, a controlled unit, a radio transceiver platform, an antenna assembly, and a cloud server. The complete component architecture is as follows: Figure 1 As shown;

[0138] The main control unit communicates with the cloud server via the network port to upload data;

[0139] The main control unit communicates with several controlled units via a wireless local area network, wherein the number of several units is greater than or equal to two.

[0140] The master controller and the controlled machine communicate with their respective subordinate radio transceiver platforms through network ports, with one radio transceiver platform corresponding to one master controller or one controlled machine.

[0141] The main control unit is used to issue drone target recognition commands, determine whether the drone in the recognition result is a registered drone, and if so, continue to issue drone target recognition commands; otherwise, issue drone positioning and sampling commands.

[0142] The main controller is used to receive positioning sampling results from the controlled device, determine whether there is a UAV signal segment in the results, and if so, continue to issue UAV positioning calculation instructions; otherwise, return to the recognition state and issue UAV target recognition instructions.

[0143] The main controller is used to forward the data segments for processing intercepted from the subordinate radio transceiver platform;

[0144] The main controller is used to receive time difference results from the controlled machine, perform multi-station positioning calculation based on arrival time difference, and upload the calculation results to the cloud server.

[0145] The controlled device is used to forward the UAV target identification command from the master controller to the subordinate radio transceiver platform and to forward the identification results from the subordinate radio transceiver platform to the master controller;

[0146] The controlled device is used to forward the UAV positioning and sampling commands from the master controller to the subordinate radio transceiver platform and to forward the positioning and sampling results from the subordinate radio transceiver platform to the master controller.

[0147] The controlled machine is used to forward the UAV positioning and calculation instructions from the master controller to the subordinate radio transceiver platform and to receive the calculation data segments from the subordinate radio transceiver platform.

[0148] The controlled machine is used to receive the calculation data segment forwarded by the master controller, perform dual-station time difference calculation locally, and transmit the time difference result to the master controller;

[0149] The radio transceiver platform is used to receive UAV target identification instructions issued by the corresponding master controller or forwarded by the corresponding controlled machine, perform UAV target identification on the radio signals received by the antenna assembly, and transmit the identification results back to the corresponding master controller or controlled machine.

[0150] The radio transceiver platform is used to receive UAV positioning and sampling instructions issued by the corresponding master controller or forwarded by the corresponding controlled machine, perform UAV positioning and sampling on the radio signals received by the antenna assembly, and transmit the UAV positioning and sampling results back to the corresponding master controller or controlled machine.

[0151] The radio transceiver platform is used to receive UAV positioning and calculation instructions issued by the corresponding master controller or forwarded by the corresponding controlled machine, extract locally cached UAV signal data through the index contained in the instruction to form a calculation data segment, and transmit the calculation data segment back to the corresponding master controller or controlled machine.

[0152] The antenna assembly is used to receive various radio signals, and its quantity is consistent with that of the radio transceiver platform.

[0153] The cloud server is used to record various work logs and provides a visual interface.

[0154] The network topology consisting of the master controller, the controlled devices, and the radio transceiver platform is as follows: Figure 2 As shown.

[0155] Specific Implementation Method Two: Combining Figure 7 This embodiment describes an identification and positioning method based on a multi-station unmanned aerial vehicle (UAV) identification and positioning system, which includes the following steps:

[0156] Step 1: The master controller communicates directly with the corresponding radio transceiver platform via the network port. The master controller also communicates with the controlled devices via a wireless LAN. The controlled devices communicate with their respective subordinate radio transceiver platforms via the network port. The master controller issues a UAV identification command. The radio transceiver platforms under the master controller and the controlled devices receive the UAV target identification command issued by the master controller or forwarded by the controlled devices. Each radio transceiver platform performs UAV target identification on the radio signals received by its corresponding antenna assembly to obtain the UAV's frequency. and drone latency value information;

[0157] One radio transceiver platform corresponds to one antenna assembly;

[0158] Step 2: The main controller determines the drone's latency value. If the drone belongs to a whitelist member, and if so, determine that it is a known drone and proceed to step one to continue drone target identification; otherwise, the drone is a suspicious drone, and the drone frequency will be... and drone latency value The information is encapsulated into UAV positioning and sampling instructions; proceed to step three.

[0159] The drone frequency point and drone latency value The information is encapsulated into UAV positioning and sampling instructions, including the following steps:

[0160] The encapsulation process of UAV positioning and sampling commands in a fixed message format (fixed prefix header and message length) includes the following steps:

[0161] 1) Synchronize sampling time The command is placed in the standard format (set t 9170000);

[0162] 2) Adjust the frequency of the drone Enter the command in the standard format (set f 5820000000);

[0163] 3) Set the target delay value Enter the command in the standard format (set d 536);

[0164] 4) Set the acquisition gain Enter the command in the standard format (set g 62);

[0165] in,

[0166] The Greenwich Mean Time is calculated by the main control unit based on the current time point with a fixed delay (e.g., 5 seconds).

[0167] This is an effective receiver gain configuration value for a radio transceiver platform (e.g., 62dB).

[0168] A target localization sampling command that meets the above requirements is as follows: Figure 5 As shown;

[0169] Step 3: The master controller issues a drone positioning and sampling command. The radio transceiver platforms under the master controller and the controlled drone receive the drone positioning and sampling command issued by the master controller or forwarded by the controlled drone, and perform drone positioning sampling on the radio signals received by their respective antenna components; after sampling is completed, a sequence is obtained. ;

[0170] The radio transceiver platform will obtain the sequence Send the data to the corresponding master or slave machine via the network port;

[0171] The controlled unit receives sequences transmitted by subordinate radio transceiver platforms. The controlled machine will sequence Forwarded to the main control unit;

[0172] The main controller receives sequences transmitted by subordinate radio transceiver platforms. The master controller receives the sequence forwarded by the controlled machine. ;

[0173] The main controller uses a time-stamp matching algorithm to calculate the most likely signal segment of the drone signal. If no most likely signal segment exists, it is judged as a false trigger, and step one is repeated; if the most likely signal segment exists, it is marked as such. Continue with step four;

[0174] Number and sequence of radio transceiver platforms The number is the same;

[0175] Step 4: The radio transceiver platform receives the UAV positioning calculation instructions issued by the corresponding master controller or forwarded by the corresponding controlled machine, transmits the corresponding radio signal sampling data to the corresponding master controller or controlled machine, completes the UAV positioning calculation locally on the controlled machine and master controller, uploads the UAV location to the cloud server, and the master controller re-executes Step 1.

[0176] Specific Implementation Method Three: This implementation method differs from Specific Implementation Method Two in that, in step one, the main control unit communicates directly with the corresponding radio transceiver platform via a network port, and the main control unit communicates with the controlled unit via a wireless local area network. The controlled unit communicates with its respective subordinate radio transceiver platforms via a network port. The main control unit issues a UAV identification command, and the radio transceiver platforms subordinate to the main control unit and the controlled unit receive the UAV target identification command issued by the main control unit or forwarded by the controlled unit. Each radio transceiver platform performs UAV target identification on the radio signals received by its corresponding antenna assembly to obtain the UAV frequency. and drone latency value Information; the specific process is as follows:

[0177] The main controller issues drone target identification commands to subordinate radio transceiver platforms, and the main controller issues drone target identification commands to all controlled drones.

[0178] The controlled device receives the UAV identification command issued by the master controller, enters the waiting state for identification results, and forwards the UAV target identification command to the subordinate radio transceiver platform;

[0179] The radio transceiver platform receives UAV target identification commands issued by the master controller or forwarded by the controlled machine through the network port;

[0180] The radio transceiver platform continuously scans the frequency range simultaneously between 2.4 GHz and 2.5 GHz and between 5.7 GHz and 5.85 GHz (which can be modified within the range of 80 MHz to 6.0 GHz) using its antenna assembly to acquire radio signals. The time-frequency diagram of the signal obtained from the frequency scan is shown below. Figure 3 As shown;

[0181] Set the relevant spectral threshold Set the time-width threshold Set a list of delay values. ;

[0182] The radio transceiver platform performs time-delay autocorrelation processing on the radio signals obtained from frequency sweeping to obtain the autocorrelation spectrum. The delay parameter iterates through the set delay value list and is based on the set correlation spectrum threshold. and time-width threshold Obtain drone frequency and drone latency value information;

[0183] The main controller or controlled unit receives the UAV frequency points transmitted by the subordinate radio transceiver platform. and drone latency value Information; the controlled aircraft forwards the UAV frequency to the main controller. and drone latency value information.

[0184] The other steps and parameters are the same as in Specific Implementation Method Two.

[0185] Specific Implementation Method Four: This implementation method differs from Specific Implementation Method One or Two in that the radio transceiver platform performs time-delay autocorrelation processing on the radio signals obtained from frequency sweeping to obtain an autocorrelation spectrum. The time delay parameter iterates through the set time delay value list and is based on the set correlation spectrum threshold. and time-width threshold Obtain drone frequency and drone latency value Information; the specific process is as follows:

[0186] 1) Initialize a single frequency band as ;

[0187] 2) Assume the radio signal in the frequency band is Select delay value ;

[0188] in A list of delay values ​​to be set;

[0189] The mathematical representation of the time-delayed autocorrelation spectrum is:

[0190]

[0191] in, For time-delayed autocorrelation spectrum;

[0192] For radio signals in complex form, for conjugate, For modulo calculation;

[0193] The radio signals processed in this invention are discrete digital signals, and to reduce computational load, the delay autocorrelation processing method used in the system is as follows:

[0194]

[0195] in, The discrete autocorrelation spectrum results are obtained by downsampling at 1 / W octave. For complex discrete radio signals, for conjugate, The selected drone delay value, To handle the long sliding window, |·| represents the cumulative offset in a single summation calculation, and |·| represents the modulo calculation. The discrete time point is the result of downsampling the original discrete signal by a factor of 1 / W, where k is an integer multiple of 1 / W. , In order to make Any natural number that satisfies the restrictions. The original signal length;

[0196] Based on the frequency band and delay value of the radio transceiver platform Searching for the corresponding autocorrelation results arrive All spectral peaks within the range are greater than the relevant spectral threshold. Autocorrelation spectrum peak (in Let k be a value that meets the requirements, such as Figure 4 (as shown);

[0197] If it exists, then the corresponding UAV frequency will be used. and drone latency value Send the data to the corresponding master or slave machine via the network port;

[0198] If it does not exist, the frequency band remains unchanged, and the calculation is performed. Find the next delay value. arrive All spectral peaks within the range are greater than the relevant spectral threshold. Autocorrelation spectrum peak If it exists, then the corresponding UAV frequency will be used. The drone latency value is sent to the corresponding master or slave device via the network port; if it does not exist, the frequency band remains unchanged, and the calculation is performed. Find the next delay value. arrive All spectral peaks within the range are greater than the relevant spectral threshold. Autocorrelation spectrum peak ;

[0199] Until the traversal is complete All delay values ​​in the middle;

[0200] express arrive The autocorrelation spectrum;

[0201] 3) Determine whether the set spectrum range has been traversed completely;

[0202] If so, obtain the drone frequency points and drone latency information for all frequency bands;

[0203] If not, jump to the next frequency band and repeat step 2) until the set frequency range has been traversed.

[0204] The other steps and parameters are the same as in specific implementation method two or three.

[0205] Specific Implementation Method Five: This implementation method differs from Specific Implementation Methods Two to Four in that, in step three, the master controller issues a UAV positioning and sampling command. The radio transceiver platforms subordinate to the master controller and the controlled UAV receive the UAV positioning and sampling command issued by the master controller or forwarded by the controlled UAV, and perform UAV positioning and sampling on the radio signals received by their respective antenna components. After sampling is completed, a sequence is obtained. ;

[0206] The radio transceiver platform will obtain the sequence Send the data to the corresponding master or slave machine via the network port;

[0207] The controlled unit receives sequences transmitted by subordinate radio transceiver platforms. The controlled machine will sequence Forwarded to the main control unit;

[0208] The main controller receives sequences transmitted by subordinate radio transceiver platforms. The master controller receives the sequence forwarded by the controlled machine. ;

[0209] The main controller uses a time-stamp matching algorithm to calculate the most likely signal segment of the drone signal. If no most likely signal segment exists, it is judged as a false trigger, and step one is repeated; if the most likely signal segment exists, it is marked as such. If so, proceed to step four;

[0210] Number and sequence of radio transceiver platforms The number is the same;

[0211] The specific process is as follows:

[0212] Step 3: The main controller sends the UAV positioning command to the subordinate radio transceiver platform, and sends the UAV positioning sampling command to all controlled devices.

[0213] The controlled device receives the UAV positioning command issued by the master controller, saves the parameters in the command, enters the waiting positioning calculation state, and forwards the UAV positioning sampling command to the subordinate radio transceiver platform.

[0214] The parameter in the instruction is the synchronous sampling time. Drone frequency Target delay value and gain settings ;

[0215] The radio transceiver platform receives UAV positioning and sampling commands issued by the corresponding master controller or forwarded by the corresponding slave controller, and sets the sampling frequency point according to the command content. and synchronous sampling time ;

[0216] The radio transceiver platform achieves local time synchronization through a time synchronization module, at the start of the synchronization sampling time. All radio transceiver platforms started simultaneously via antenna assemblies. Sampling of UAV radio signals at specific frequencies;

[0217] Step 3.2: After sampling is completed, each radio transceiver platform obtains radio signal sampling data. The target delay value provided by the positioning sampling command is cached locally and used locally. Delayed autocorrelation preprocessing is performed to obtain autocorrelation results, and then the autocorrelation results are searched for... arrive All spectral peaks within the range are greater than the relevant spectral threshold. Autocorrelation spectrum peak of Let it be the starting index subscript. ,like Figure 6 As shown;

[0218] express arrive The peak value of the autocorrelation spectrum; This indicates that the conditions for obtaining the value are met. , The discretized time point is the original discrete signal after being downsampled by a factor of 1 / W. Indicates the time-width threshold;

[0219] Based on all index subscripts Composition sequence ;

[0220] The radio transceiver platform will obtain the sequence Send the data to the corresponding master or slave machine via the network port;

[0221] The controlled unit receives sequences transmitted by subordinate radio transceiver platforms. The controlled machine will sequence Forwarded to the main control unit;

[0222] The main controller receives sequences transmitted by subordinate radio transceiver platforms. The master controller receives the sequence forwarded by the controlled machine. ;

[0223] The main controller uses a time-stamp matching algorithm to calculate whether the drone signal contains the most likely signal segment. If no most likely signal segment exists, it is determined to be a false trigger, and step one is repeated. If the most likely signal segment exists, its starting index is marked as [index missing]. If so, proceed to step four.

[0224] Number and sequence of radio transceiver platforms The number is the same;

[0225] The other steps and parameters are the same as those in one of the specific implementation methods two to four.

[0226] Specific Implementation Method Six: This implementation method differs from Specific Implementation Methods Two to Five in that the main controller uses a time-stamp matching algorithm to calculate the most probable signal segment of the UAV signal. If no most probable signal segment exists, it is determined to be a false trigger, and step one is re-executed; if a most probable signal segment exists, the starting index of the most probable signal segment is marked as... The specific process is as follows:

[0227] 1): Set the matching window length ;

[0228] 2): Find all sequences Maximum index value in ;

[0229] 3): Order ;

[0230] 4): When each sequence All of them exist in The index in the range marks the current position. For index ;

[0231] 5), let Repeat step 4) until... To obtain the starting index of the most likely signal segment. ;

[0232] If the traversal ends and no matching condition is found... This segment is determined to be the most likely to be nonexistent.

[0233] An example of a time-scaled matching algorithm is as follows:

[0234] The system consists of one master controller, three slave controllers, and four stations. The sequences are [243394,462518,681512], [531,243883,463007,902054], [462890,901767], and [464108,683133], with matching window lengths of [missing information]. The algorithm then calculates the starting index of the most probable signal segment. .

[0235] The other steps and parameters are the same as those in one of the specific implementation methods two to five.

[0236] Specific Implementation Method Seven: This implementation method differs from one of Specific Implementation Methods Two to Six in that, in step four, the radio transceiver platform is used to receive the UAV positioning calculation instruction issued by the corresponding master controller or forwarded by the corresponding controlled machine, transmit the corresponding radio signal sampling data to the corresponding master controller or controlled machine, complete the UAV positioning calculation locally on the controlled machine and the master controller, upload the UAV location to the cloud server, and the master controller re-executes step one.

[0237] The specific process is as follows:

[0238] The main controller will use the starting index of the most likely signal segment. The commands are packaged into UAV positioning and calculation instructions. The main controller sends the UAV positioning and calculation instructions to the subordinate radio transceiver platforms and to all controlled UAVs.

[0239] The starting index of the most likely signal segment. Place the instructions in the standard format;

[0240] An example of a UAV positioning and solving command that meets the above requirements is shown below:

[0241] ned t 462518

[0242] in, The value is 462518;

[0243] The controlled device receives the UAV positioning and calculation instructions from the master controller, and then forwards the UAV positioning and calculation instructions to its subordinate radio transceiver platform.

[0244] The radio transceiver platform receives UAV positioning and calculation commands from the corresponding master controller or the corresponding controlled device, and determines the location based on the starting index of the most likely signal segment. Extract the corresponding fixed length from the local cache (in this invention) Radio signal sampling data with a value of 10240 ;

[0245] for Extract from the middle Starting from, A signal segment of length 1;

[0246] The radio transceiver platform will intercept the data. Transmitted to the corresponding master or slave unit;

[0247] The main control unit receives intercepted data transmitted from the subordinate radio transceiver platform. Then, it is forwarded to each controlled machine;

[0248] After receiving intercepted data transmitted from subordinate radio transceiver platforms and intercepted data forwarded by the master controller, the controlled unit performs bi-station time difference calculation locally using a matched filtering algorithm to obtain the time difference result. ;

[0249] The controlled machine will display the time difference results. Transmitted to the main control unit;

[0250] The master controller receives the time difference results transmitted by all the controlled machines. Then, the local machine performs Time Difference of Arrival (TDOA) positioning calculation based on the location information of each station to calculate the drone's location, and uploads the drone's location to the cloud server. The main control unit then re-executes step one.

[0251] The other steps and parameters are the same as those in one of the specific implementation methods two to six.

[0252] Specific Implementation Method Eight: This implementation method differs from Specific Implementation Methods Two to Seven in that it uses a matched filtering algorithm to calculate the time difference between the two stations and obtain the time difference result. The specific process is as follows:

[0253] Assuming the intercepted data forwarded from the main control unit is The intercepted data obtained directly by the controlled machine from the subordinate radio transceiver platform is ;

[0254] 1) and All are converted to the frequency domain using Fourier transform, and the calculation method is as follows:

[0255]

[0256]

[0257] in, for Frequency domain signal after Fourier transform; for Frequency domain signal after Fourier transform;

[0258] This is a Fourier transform; the number of Fourier transform points used is (2L1-1);

[0259] 2) and Performing a matched filter operation in the frequency domain and converting back to the time domain, the calculation method is as follows:

[0260]

[0261] in, for Conjugate;

[0262] This is the inverse Fourier transform;

[0263] The result of the matched filtering;

[0264] 3) In Find the index of the largest spectral peak The time difference result is obtained after coordinate mapping. The coordinate mapping method is as follows:

[0265] .

[0266] The other steps and parameters are the same as those in one of the specific implementation methods 2 to 7.

[0267] Specific Implementation Method Nine: This implementation method differs from Specific Implementation Methods Two to Eight in that the master controller receives the time difference results transmitted by all controlled machines. Then, the location of the UAV is calculated locally by combining the location information from each station with the Time Difference of Arrival (TDOA) calculation; the specific process is as follows:

[0268] 1) Taking a 4-station system as an example, the calculated time differences between the master control station and the three controlled stations are as follows: , , ,based on , , Obtain the time difference vector ;

[0269] 2) The main control unit obtains and caches the coordinates of the main control unit station in the geodetic coordinate system through the time synchronization module. ;

[0270] The master controller and the controlled machine communicate periodically to obtain and cache the coordinates of the controlled machine's station in the geodetic coordinate system. The coordinates of the controlled machine 2 station in the geodetic coordinate system The coordinates of the three controlled stations in the geodetic coordinate system ;

[0271] 3) The main control unit uses the National Geodetic Coordinate System (CGCS2000) model to determine the coordinates of the main control unit's station in the geodetic coordinate system. Convert to Cartesian coordinate system ;

[0272] The coordinates of the controlled machine 1 station in the geodetic coordinate system Convert to Cartesian coordinate system ;

[0273] The coordinates of the controlled machine 2 station in the geodetic coordinate system Convert to Cartesian coordinate system ;

[0274] The coordinates of the three controlled machine stations in the geodetic coordinate system Convert to Cartesian coordinate system ;

[0275] 4) Based on and the speed of light get , ;

[0276] based on and the speed of light get , ;

[0277] based on and the speed of light get , ;

[0278] based on , , To obtain the distance difference vector ;

[0279] in, This is the difference between the distance from the drone to the controlled station 1 and the distance from the drone to the master control station. This is the difference between the distance from the drone to the controlled station 2 and the distance from the drone to the main control station. This is the difference between the distance from the UAV to the controlled station 3 and the distance from the UAV to the main control station;

[0280] 5) Assume the target position coordinates of the UAV in the rectangular coordinate system are: The distance from the target to the main control unit is Establish a system of equations:

[0281]

[0282] in, The square of the norm;

[0283] The target position of the UAV in the rectangular coordinate system is obtained by solving the system of equations using the least squares method. ;

[0284] 6) The main control unit uses the national geodetic coordinate system model to convert the UAV target position in the rectangular coordinate system to the UAV target position in the geodetic coordinate system. ;

[0285] The main controller will display the target position of the UAV in the geodetic coordinate system. Uploaded to the cloud server, the main control unit re-executes step one.

[0286] The other steps and parameters are the same as those in specific implementation methods two to eight.

[0287] Specific Implementation Method 10: This implementation method differs from one of Specific Implementation Methods 2 to 9 in that there is timed message communication between the master controller and the controlled machine;

[0288] When the controlled machine comes online, it automatically establishes a message communication connection with the main control machine through the wireless self-organizing network module.

[0289] The message communication includes the controlled machine sending its online status identifier and local location information to the master machine, and the master machine sending confirmation information to the controlled machine.

[0290] The cloud server interacts with the main control computer via a network port.

[0291] The cloud server has a built-in offline map. By acquiring data from the main control unit, the cloud server displays the real-time location information of the main control unit (the coordinates of the main control unit's location in the geodetic coordinate system). Controlled machine location information (coordinates of controlled machine 1 station in the geodetic coordinate system) Coordinates of the controlled machine at station 2 in the geodetic coordinate system Coordinates of the three controlled stations in the geodetic coordinate system It also displays the drone's location information (target location) when the drone is located. ).

[0292] The other steps and parameters are the same as those in one of the specific implementation methods 2 to 9.

[0293] This invention may have other embodiments. Without departing from the spirit and essence of this invention, those skilled in the art can make various corresponding changes and modifications according to this invention, but these corresponding changes and modifications should all fall within the protection scope of the appended claims.

Claims

1. A multi-station unmanned aerial vehicle (UAV) identification and positioning system, characterized in that: The system includes: a main controller, a controlled device, a radio transceiver platform, an antenna assembly, and a cloud server; The main control unit communicates with the cloud server via the network port to upload data; The main control unit communicates with several controlled units via a wireless local area network, wherein the number of several units is greater than or equal to two. The master controller and the controlled machine communicate with their respective subordinate radio transceiver platforms through network ports, with one radio transceiver platform corresponding to one master controller or one controlled machine. The main control unit is used to issue drone target recognition commands, determine whether the drone in the recognition result is a registered drone, and if so, continue to issue drone target recognition commands; otherwise, issue drone positioning and sampling commands. The main controller is used to receive positioning sampling results from the controlled device, determine whether there is a UAV signal segment in the results, and if so, continue to issue UAV positioning calculation instructions; otherwise, return to the recognition state and issue UAV target recognition instructions. The main controller is used to forward the data segments for processing intercepted from the subordinate radio transceiver platform; The main controller is used to receive time difference results from the controlled machine, perform multi-station positioning calculation based on arrival time difference, and upload the calculation results to the cloud server. The controlled device is used to forward the UAV target identification command from the master controller to the subordinate radio transceiver platform and to forward the identification results from the subordinate radio transceiver platform to the master controller; The controlled device is used to forward the UAV positioning and sampling commands from the master controller to the subordinate radio transceiver platform and to forward the positioning and sampling results from the subordinate radio transceiver platform to the master controller. The controlled machine is used to forward the UAV positioning and calculation instructions from the master controller to the subordinate radio transceiver platform and to receive the calculation data segments from the subordinate radio transceiver platform. The controlled machine is used to receive the calculation data segment forwarded by the master controller, perform dual-station time difference calculation locally, and transmit the time difference result to the master controller; The radio transceiver platform is used to receive UAV target identification instructions issued by the corresponding master controller or forwarded by the corresponding controlled machine, perform UAV target identification on the radio signals received by the antenna assembly, and transmit the identification results back to the corresponding master controller or controlled machine. The radio transceiver platform is used to receive UAV positioning and sampling instructions issued by the corresponding master controller or forwarded by the corresponding controlled machine, perform UAV positioning and sampling on the radio signals received by the antenna assembly, and transmit the UAV positioning and sampling results back to the corresponding master controller or controlled machine. The radio transceiver platform is used to receive UAV positioning and calculation instructions issued by the corresponding master controller or forwarded by the corresponding controlled machine, extract locally cached UAV signal data through the index contained in the instruction to form a calculation data segment, and transmit the calculation data segment back to the corresponding master controller or controlled machine. The antenna assembly is used to receive various radio signals, and its quantity is consistent with that of the radio transceiver platform. The cloud server is used to record various work logs.

2. A multi-station UAV identification and positioning method, characterized in that: The specific process of the method is as follows: Step 1: The master controller communicates directly with the corresponding radio transceiver platform via the network port. The master controller also communicates with the controlled devices via a wireless LAN. The controlled devices communicate with their respective subordinate radio transceiver platforms via the network port. The master controller issues a UAV identification command. The radio transceiver platforms under the master controller and the controlled devices receive the UAV target identification command issued by the master controller or forwarded by the controlled devices. Each radio transceiver platform performs UAV target identification on the radio signals received by its corresponding antenna assembly to obtain the UAV's frequency. and drone latency value information; Step 2: The main controller determines the drone's latency value. If the drone belongs to a whitelist member, and if so, determine that it is a known drone and proceed to step one to continue drone target identification; otherwise, the drone is a suspicious drone, and the drone frequency will be changed. and drone latency value The information is encapsulated into UAV positioning and sampling instructions; proceed to step three. Step 3: The main controller issues a drone positioning and sampling command. The radio transceiver platforms under the main controller and the controlled drone receive the drone positioning and sampling command issued by the main controller or forwarded by the controlled drone, and perform drone positioning and sampling on the radio signals received by their respective antenna components. The sequence is obtained after sampling. ; The radio transceiver platform will obtain the sequence Send the data to the corresponding master or slave machine via the network port; The controlled unit receives sequences transmitted by subordinate radio transceiver platforms. The controlled machine will sequence Forwarded to the main control unit; The main controller receives sequences transmitted by subordinate radio transceiver platforms. The master controller receives the sequence forwarded by the controlled machine. ; The main controller uses a time-stamp matching algorithm to calculate the most likely signal segment of the drone signal. If no most likely signal segment exists, it is judged as a false trigger, and step one is repeated; if the most likely signal segment exists, it is marked as such. Continue to step four; Step 4: The radio transceiver platform receives the UAV positioning calculation instructions issued by the corresponding master controller or forwarded by the corresponding controlled machine, transmits the corresponding radio signal sampling data to the corresponding master controller or controlled machine, completes the UAV positioning calculation locally on the controlled machine and master controller, uploads the UAV location to the cloud server, and the master controller re-executes Step 1.

3. The multi-station UAV identification and positioning method according to claim 2, characterized in that: In step one, the master controller communicates directly with the corresponding radio transceiver platform via a network port, and with the controlled device via a wireless LAN. The controlled device communicates with its respective subordinate radio transceiver platforms via a network port. The master controller issues a UAV identification command, and the radio transceiver platforms subordinate to the master controller and the controlled device receive the UAV target identification command issued by the master controller or forwarded by the controlled device. Each radio transceiver platform performs UAV target identification on the radio signals received by its corresponding antenna assembly to obtain the UAV frequency. and drone latency value Information; the specific process is as follows: The main controller issues drone target identification commands to subordinate radio transceiver platforms, and the main controller issues drone target identification commands to all controlled drones. The controlled device receives the UAV identification command issued by the master controller, enters the waiting state for identification results, and forwards the UAV target identification command to the subordinate radio transceiver platform; The radio transceiver platform receives UAV target identification commands issued by the master controller or forwarded by the controlled machine through the network port; The radio transceiver platform acquires radio signals by continuously scanning frequencies in the 2.4 GHz to 2.5 GHz and 5.7 GHz to 5.85 GHz ranges simultaneously using an antenna assembly. Set the relevant spectral threshold Set the time-width threshold Set a list of delay values. ; The radio transceiver platform performs time-delay autocorrelation processing on the radio signals obtained from frequency sweeping to obtain the autocorrelation spectrum. The delay parameter iterates through the set delay value list and is based on the set correlation spectrum threshold. and time-width threshold Obtain drone frequency and drone latency value information; The main controller or controlled unit receives the UAV frequency points transmitted by the subordinate radio transceiver platform. and drone latency value information; The controlled device forwards the UAV frequency to the main controller. and drone latency value information.

4. The multi-station UAV identification and positioning method according to claim 3, characterized in that: The radio transceiver platform performs time-delay autocorrelation processing on the frequency-scanned radio signals to obtain the autocorrelation spectrum. The time delay parameter iterates through a list of set time delay values ​​and is based on a set correlation spectrum threshold. and time-width threshold Obtain drone frequency and drone latency value Information; the specific process is as follows: 1) Initialize a single frequency band as ; 2) Assume the radio signal in the frequency band is Select delay value ; in A list of delay values ​​to be set; The delayed autocorrelation processing method is as follows: in, The discrete autocorrelation spectrum results are obtained by downsampling at 1 / W octave. For complex discrete radio signals, for conjugate, The selected drone delay value, To handle the long sliding window, |·| represents the cumulative offset in a single summation calculation, and |·| represents the modulo calculation. The discrete time point is the result of downsampling the original discrete signal by a factor of 1 / W, where k is an integer multiple. , In order to make Any natural number that satisfies the restrictions. The original signal length; Based on the frequency band and delay value of the radio transceiver platform Searching for the corresponding autocorrelation results arrive All spectral peaks within the range are greater than the relevant spectral threshold. Autocorrelation spectrum peak ; If it exists, then the corresponding UAV frequency will be used. and drone latency value Send the data to the corresponding master or slave machine via the network port; If it does not exist, the frequency band remains unchanged, and the calculation is performed. Find the next delay value. arrive All spectral peaks within the range are greater than the relevant spectral threshold. Autocorrelation spectrum peak If it exists, then the corresponding UAV frequency will be used. The drone latency value is sent to the corresponding master or slave device via the network port; if it does not exist, the frequency band remains unchanged, and the calculation is performed. Find the next delay value. arrive All spectral peaks within the range are greater than the relevant spectral threshold. Autocorrelation spectrum peak ; Until the traversal is complete All delay values ​​in the middle; express arrive The autocorrelation spectrum; 3) Determine whether the set spectrum range has been traversed completely; If so, obtain the drone frequency points and drone latency information for all frequency bands; If not, jump to the next frequency band and repeat step 2) until the set frequency range has been traversed.

5. The multi-station UAV identification and positioning method according to claim 4, characterized in that: In step three, the main controller issues a drone positioning and sampling command. The radio transceiver platforms under the main controller and the controlled drone receive the drone positioning and sampling command issued by the main controller or forwarded by the controlled drone, and perform drone positioning and sampling on the radio signals received by their respective antenna components. The sequence is obtained after sampling. ; The radio transceiver platform will obtain the sequence Send the data to the corresponding master or slave machine via the network port; The controlled unit receives sequences transmitted by subordinate radio transceiver platforms. The controlled machine will sequence Forwarded to the main control unit; The main controller receives sequences transmitted by subordinate radio transceiver platforms. The master controller receives the sequence forwarded by the controlled machine. ; The main controller uses a time-stamp matching algorithm to calculate the most likely signal segment of the drone signal. If no most likely signal segment exists, it is judged as a false trigger, and step one is repeated; if the most likely signal segment exists, it is marked as such. If so, proceed to step four; The specific process is as follows: Step 3: The main controller sends the UAV positioning command to the subordinate radio transceiver platform, and sends the UAV positioning sampling command to all controlled devices. The controlled device receives the UAV positioning command issued by the master controller, saves the parameters in the command, enters the waiting positioning calculation state, and forwards the UAV positioning sampling command to the subordinate radio transceiver platform. The parameter in the instruction is the synchronous sampling time. Drone frequency Target delay value and gain settings ; The radio transceiver platform receives UAV positioning and sampling commands issued by the corresponding master controller or forwarded by the corresponding slave controller, and sets the sampling frequency point according to the command content. and synchronous sampling time ; The radio transceiver platform achieves local time synchronization through a time synchronization module, at the start of the synchronization sampling time. All radio transceiver platforms started simultaneously via antenna assemblies. Sampling of UAV radio signals at specific frequencies; Step 3.2: After sampling is completed, each radio transceiver platform obtains radio signal sampling data. The target delay value provided by the positioning sampling command is cached locally and used locally. Delayed autocorrelation preprocessing is performed to obtain autocorrelation results, and then the autocorrelation results are searched for... arrive All spectral peaks within the range are greater than the relevant spectral threshold. Autocorrelation spectrum peak of Let it be the starting index subscript. ; express arrive The peak value of the autocorrelation spectrum; This indicates that the conditions for obtaining the value are met. , The discretized time point is the original discrete signal after being downsampled by a factor of 1 / W. Indicates the time-width threshold; Based on all index subscripts Composition sequence ; The radio transceiver platform will obtain the sequence Send the data to the corresponding master or slave machine via the network port; The controlled unit receives sequences transmitted by subordinate radio transceiver platforms. The controlled machine will sequence Forwarded to the main control unit; The main controller receives sequences transmitted by subordinate radio transceiver platforms. The master controller receives the sequence forwarded by the controlled machine. ; The main controller uses a time-stamp matching algorithm to calculate whether the drone signal contains the most likely signal segment. If no most likely signal segment exists, it is determined to be a false trigger, and step one is repeated. If the most likely signal segment exists, its starting index is marked as [index missing]. If so, proceed to step four.

6. The multi-station UAV identification and positioning method according to claim 5, characterized in that: The main controller uses a time-stamp matching algorithm to calculate whether the UAV signal contains the most likely signal segment. If no most likely signal segment exists, it is determined to be a false trigger, and step one is repeated. If the most likely signal segment exists, the starting index of the most likely signal segment is marked as... ; The specific process is as follows: 1): Set the matching window length ; 2): Find all sequences Maximum index value in ; 3): Order ; 4): When each sequence All of them exist in The index in the range marks the current position. For index ; 5), let Repeat step 4) until... To obtain the starting index of the most likely signal segment. ; If the traversal ends and no matching condition is found... This segment is determined to be the most likely to be nonexistent.

7. The multi-station UAV identification and positioning method according to claim 6, characterized in that: In step four, the radio transceiver platform receives the UAV positioning calculation command issued by the corresponding master controller or forwarded by the corresponding controlled device, transmits the corresponding radio signal sampling data to the corresponding master controller or controlled device, completes the UAV positioning calculation locally on the controlled device and master controller, uploads the UAV location to the cloud server, and the master controller re-executes step one; the specific process is as follows: The main controller will use the starting index of the most likely signal segment. The commands are packaged into UAV positioning and calculation instructions. The main controller sends the UAV positioning and calculation instructions to the subordinate radio transceiver platforms and to all controlled UAVs. The controlled device receives the UAV positioning and calculation instructions from the master controller, and then forwards the UAV positioning and calculation instructions to its subordinate radio transceiver platform. The radio transceiver platform receives UAV positioning and calculation commands from the corresponding master controller or forwarded by the corresponding slave controller, and determines the location based on the starting index of the most likely signal segment. Extract the corresponding fixed length from the local cache Radio signal sampling data ; for Extract from the middle Starting from, A signal segment of length 1; The radio transceiver platform will intercept the data. Transmitted to the corresponding master or slave unit; The main control unit receives intercepted data transmitted from the subordinate radio transceiver platform. Then, it is forwarded to each controlled machine; After receiving intercepted data transmitted from subordinate radio transceiver platforms and intercepted data forwarded by the master controller, the controlled unit performs bi-station time difference calculation locally using a matched filtering algorithm to obtain the time difference result. ; The controlled machine will display the time difference results. Transmitted to the main control unit; The master controller receives the time difference results transmitted by all the controlled machines. Then, the local machine combines the location information of each station to perform positioning calculation based on the time difference of arrival, calculates the drone's location, and uploads the drone's location to the cloud server. The main control unit then re-executes step one.

8. The multi-station UAV identification and positioning method according to claim 7, characterized in that: The matched filtering algorithm is used to calculate the time difference between the two stations, and the time difference results are obtained. The specific process is as follows: Assuming the intercepted data forwarded from the main control unit is The intercepted data obtained directly by the controlled machine from the subordinate radio transceiver platform is ; 1) and All are converted to the frequency domain using Fourier transform, and the calculation method is as follows: in, for Frequency domain signal after Fourier transform; for Frequency domain signal after Fourier transform; Fourier transform; 2) and Performing a matched filter operation in the frequency domain and converting back to the time domain, the calculation method is as follows: in, for The conjugate; This is the inverse Fourier transform; The result of the matched filtering; 3) In Find the index of the largest spectral peak The time difference result is obtained after coordinate mapping. The coordinate mapping method is as follows: 。 9. A multi-station UAV identification and positioning method according to claim 8, characterized in that: The master controller receives the time difference results transmitted by all the controlled machines. Then, the location of the drone is calculated locally based on the time difference of arrival by combining the location information of each station; the specific process is as follows: 1) The calculated time differences between the master control station and the three controlled stations are as follows: , , ,based on , , Obtain the time difference vector ; 2) The main control unit obtains and caches the coordinates of the main control unit station in the geodetic coordinate system through the time synchronization module. ; The master controller and the controlled machine communicate periodically to obtain and cache the coordinates of the controlled machine's station in the geodetic coordinate system. The coordinates of the controlled machine 2 station in the geodetic coordinate system The coordinates of the three controlled stations in the geodetic coordinate system ; 3) Set the coordinates of the main control station in the geodetic coordinate system. Convert to Cartesian coordinate system ; The coordinates of the controlled machine 1 station in the geodetic coordinate system Convert to Cartesian coordinate system ; The coordinates of the controlled machine 2 station in the geodetic coordinate system Convert to Cartesian coordinate system ; The coordinates of the three controlled machine stations in the geodetic coordinate system Convert to Cartesian coordinate system ; 4) Based on and the speed of light get , ; based on and the speed of light get , ; based on and the speed of light get , ; based on , , To obtain the distance difference vector ; in, This is the difference between the distance from the drone to the controlled station 1 and the distance from the drone to the master control station. This is the difference between the distance from the drone to the controlled station 2 and the distance from the drone to the main control station. This is the difference between the distance from the UAV to the controlled station 3 and the distance from the UAV to the main control station; 5) Assume the target position coordinates of the UAV in the rectangular coordinate system are: The distance from the target to the main control unit is Establish a system of equations: in, The square of the norm; The target position of the UAV in the rectangular coordinate system is obtained by solving the system of equations using the least squares method. ; 6) Convert the UAV target position from the Cartesian coordinate system to the geodetic coordinate system. ; The main controller will display the target position of the UAV in the geodetic coordinate system. Uploaded to the cloud server, the main control unit re-executes step one.

10. A multi-station UAV identification and positioning method according to claim 9, characterized in that: There is timed message communication between the master controller and the controlled machine; When the controlled machine comes online, it automatically establishes a message communication connection with the main control machine through the wireless self-organizing network module. The message communication includes the controlled machine sending its online status identifier and local location information to the master machine, and the master machine sending confirmation information to the controlled machine. The cloud server interacts with the main control computer via a network port. The cloud server has a built-in offline map. By acquiring data from the main controller, the cloud server displays the location information of the main controller and the controlled device in real time, and displays the location information of the drone when it is located.

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