Unmanned aerial vehicle remote identification method and system

Abstract

The invention discloses an unmanned aerial vehicle remote identification method and system, and relates to the technical field of unmanned aerial vehicle identification, and the method comprises the steps: receiving remote identification data broadcasted by a target unmanned aerial vehicle through a wireless communication protocol; analyzing the remote identification data, and extracting unmanned aerial vehicle position information, control station position information and unmanned aerial vehicle identification information according to a message type field; in a network connection state, calling a map interface to display the track of the unmanned aerial vehicle and the position of the control station in real time; and under the state of no network connection, converting the position information into a plane-coordinate system, and generating a position mark and a historical track in an offline map. Through multi-protocol compatibility, dynamic network adaptation, high-precision data analysis and resource optimization design, the technical problems of strong network dependence, insufficient standard coverage, large decoding error, low offline map precision and the like existing in unmanned aerial vehicle remote identification in the prior art are solved; the real-time performance, the reliability and the user experience of unmanned aerial vehicle supervision are remarkably improved, and wide application value is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of unmanned aerial vehicle identification, and in particular to a method and system for remotely identifying an unmanned aerial vehicle. Background Art

[0002] With the booming development of the low-altitude economy, drones are increasingly being used in various industries, especially in logistics distribution, agricultural monitoring, environmental protection and other fields, where they have achieved remarkable results. However, with the surge in the number of drones, potential safety hazards in the air have gradually emerged, especially in the management and supervision of drone flights. Although relevant laws and regulations are being gradually improved, the public still lacks effective means to monitor unknown drones in the air and cannot promptly detect potential illegal flight behaviors, which creates safety hazards.

[0003] At present, common drone identification technologies mainly rely on two methods: radio frequency identification (RFID) and radar identification. RFID technology determines whether there is drone activity by monitoring whether there are drone image transmission signals that meet specific characteristics in the identification area. Radar identification technology scans the airspace through radar waves to detect and track the flight trajectory of drones. Although these two technologies can detect the presence of drones and track their flight paths, they are usually unable to obtain detailed identity information of drones, such as model, registration information, or the real-time location of the operator. This lack of information poses a huge challenge to the effective supervision of drones and lays hidden dangers for potential illegal flights.

[0004] In order to make up for the shortcomings of existing technologies, drone remote identification technology came into being. This technology enables more accurate and comprehensive identification by actively broadcasting key data such as the drone's own location information, the control station's location information, and the drone's serial number. Compared with traditional radio frequency and radar identification technologies, remote identification technology can not only identify the existence of drones, but also provide detailed identity information, including the drone's flight trajectory and the operator's geographic location, providing more data support for the effective supervision of drones. However, existing technologies still face problems such as communication stability, distance limitations, and network dependence, and are in urgent need of further improvement and innovation to adapt to more complex application environments. Summary of the invention

[0005] The purpose of the present invention is to provide a method and system for remote identification of unmanned aerial vehicles (UAVs) to solve the limitations of existing UAV remote identification technologies, such as strong network dependence, insufficient standard coverage, large decoding errors, and low offline map accuracy. Through multi-protocol compatibility, dynamic network adaptation, high-precision data analysis, and resource optimization design, the real-time, reliability, and user experience of UAV supervision are significantly improved, ensuring that UAV dynamics can be efficiently and accurately identified and monitored in various network environments, providing strong technical support for the safe flight and effective management of UAVs.

[0006] In order to achieve the above object, the present invention is implemented by the following technical solutions:

[0007] A method for remotely identifying a drone, comprising: Receive remote identification data broadcast by the target UAV through a wireless communication protocol, the data including UAV location information, control station location information and UAV identification information; Parsing the remote identification data, extracting drone location information, control station location information and drone identification information according to the message type field; When connected to the network, call the map interface to display the drone trajectory and control station location in real time; In the absence of a network connection, the location information is converted into a plane coordinate system, and a location mark and a historical track are generated in an offline map.

[0008] As a preferred solution of the present invention, the wireless communication protocol includes a Bluetooth protocol and a Wi-Fi protocol, and the target UAV complies with GB 42590-2023, ASTM F3411-22a or ASD-STAN prEN 4709-002 standards.

[0009] As a preferred solution of the present invention, the step of receiving remote identification data through the Bluetooth protocol includes: When using the Bluetooth Legacy protocol, follow these steps: (a) Establish a continuous listening link on Bluetooth advertising channels 37, 38 and 39; (b) after capturing the broadcast data packet transmitted on the channel, parsing the service data advertisement structure whose AD Type field is 0x16 in the data packet; (c) verifying whether the UUID field in the service data advertisement structure is a preset identifier 0xFFFA; (d) when the UUID field verification passes, intercepting the continuous 25 bytes of data after the UUID field from the service data advertisement structure as the original remote identification message; When using Bluetooth 5.0 and above, follow these steps: (i) Simultaneously monitor Bluetooth basic advertising channels 37, 38, 39 and extended advertising channel group; (ii) parsing the PDU header information in the received broadcast packet and identifying the broadcast indication packet carrying the auxiliary pointer field; (iii) receiving a corresponding auxiliary broadcast packet on a designated extended channel according to the channel mapping index and data offset parameter recorded in the auxiliary pointer field; (iv) Separate the 25-byte original remote identification message from the payload data segment of the auxiliary broadcast packet.

[0010] As a preferred solution of the present invention, the step of receiving remote identification data through the Wi-Fi protocol includes: (1) When using Wi-Fi NAN mode, follow the steps below: Capture Wi-Fi management frames in the preset working frequency band and filter out messages with a frame type of 0x00 and a subtype of Action; Parse the vendor identification field of the message, verify whether the OUI field value is the preset value 50-6F-9A, and simultaneously check whether the OUI Type field is 0x13; When the field verification passes, decoding and extracting the remote identification payload from the data field of the message according to the format definition of the NAN service discovery frame; (2) When using Wi-Fi Beacon mode, follow the steps below: Continuously listen to management frames on the Wi-Fi basic channel and filter broadcast messages with a frame type of 0x00 and a subtype of Beacon. Parse the vendor specific information element in the broadcast message, verify whether its OUI field value is the preset value FA-0B-BC, and verify whether the vendor type field Vendor Type field is 0x0D; The remote identification payload is separated from the payload content of the information element according to the manufacturer-defined data format.

[0011] As a preferred solution of the present invention, the steps of parsing the remote identification data include: When a data packet is packaged as a message, the following operations are performed: Read the sub-message length of the first byte and the number of sub-messages of the second byte in the message package message content; Calculate the total length according to the sub-message length and the number of sub-messages, and intercept the corresponding byte stream; Splitting the byte stream into multiple sub-messages according to a preset byte length; For each sub-message, the corresponding parsing rule is called according to its message type field for decoding; When the data packet is an independent message, decoding is performed directly according to the message type field of the independent message matching the preset parsing rule.

[0012] As a preferred solution of the present invention, the message type includes at least one of the following: Parse the basic ID message to extract the drone serial number and drone type, where the drone type is an enumeration type with a value range of 0-15; Parse the position vector message to extract the longitude, latitude, ground speed and heading angle of the drone, where: the heading angle is dynamically corrected based on the E / W direction flag bit. When the flag bit is 1, the heading angle calculation value increases by 180 degrees; the ground speed is decoded according to the speed multiplier flag bit. If the flag bit is 1, the ground speed = the encoded value × the first preset coefficient, otherwise the ground speed = the encoded value × the second preset coefficient + the third preset coefficient; the vertical speed is converted into floating-point data by multiplying the encoded value by the fourth preset coefficient; The system message is parsed to extract the control station location type and the operating area radius, wherein: the control station location type includes a take-off point, a dynamic control station or a fixed control station; the operating area radius generates an actual physical distance value by multiplying the coded value by a distance conversion coefficient.

[0013] As a preferred solution of the present invention, the analysis of the longitude and latitude of the drone includes: Reverse the byte order of the longitude and latitude fields encoded in little endian order to generate 32-bit signed integer data with the high-order byte first and the low-order byte last; The 32-bit signed integer data are divided by the preset scaling factor to obtain double-precision floating-point longitude coordinates and latitude coordinates.

[0014] As a preferred solution of the present invention, the transformation of the plane coordinate system is based on the Mercator projection rule, specifically including: Convert the units of the longitude λ and latitude φ of the drone from degrees to radians, and the calculation formula is: ; in: is the longitude of the drone, in degrees; is the latitude of the drone, in degrees; is the pi constant; is the arc value of the drone's longitude; is the arc value of the drone's latitude; Calculate the plane coordinates x and y based on the Mercator projection rules: ; in: is the east-west coordinate; is the north-south coordinate; R is the equatorial radius of the earth, which is 6378137 meters; According to the preset resolution r, the plane coordinates are converted to pixel coordinates: ; in: , is the pixel coordinate on the map; The map display resolution is used to control the coordinate scaling.

[0015] As a preferred solution of the present invention, the step of displaying the offline map includes: Establishing a mapping cache table between drone serial numbers and historical trajectories, wherein the cache table uses a key-value pair structure to store pixel coordinate historical data associated with drone serial numbers; When it is detected that a drone with a certain serial number has not updated data within a preset time period, the historical trajectory data is transferred to the local database and the corresponding cache resources are released.

[0016] A UAV remote identification system, comprising: The data receiving module comprises: a Bluetooth receiving unit configured to monitor channels 37, 38, and 39 in Bluetooth traditional mode and to parse the auxiliary pointer field to locate auxiliary advertising packets in Bluetooth 5.0 and above long-range mode; The Wi-Fi receiving unit is configured to filter management frames with an OUI value of 50-6F-9A in NAN mode and extract payload data in a vendor-specific information element format in Beacon mode; Parsing engine modules, including: A message segmentation unit configured to segment the message package message into byte streams according to the length and number of sub-messages; a byte order conversion unit configured to perform little endian to host order conversion on the latitude, longitude, altitude, and timestamp fields; Visualization module, including: An online rendering unit is configured to call a map service interface to dynamically display the trajectory of the drone and the location of the control station, and load corresponding icons according to the type of drone; An offline rendering unit, configured to generate static maps based on the Mercator projection and support caching and archiving of historical trajectory data.

[0017] It should be noted that Wi-Fi will receive signals from both 2.4G and 5G bands; Filter the received data according to specific rules to filter out the remote identification data sent by the drone; Analyze the data and select the corresponding parser for parsing according to the data type; Draw the flight trajectory of the drone on the map based on the real-time latitude and longitude data of the drone in the analysis results; According to the real-time latitude and longitude data of the control station in the analysis results, the location of the drone control station is displayed on the map; After analyzing other important data, it will be displayed in real time on the interface; When multiple drones appear in the nearby airspace, the tracks and control station locations of multiple drones can be switched to display; When the system does not receive the signal of a discovered drone for a certain period of time, it will save the drone's recent historical data; When a saved drone appears again, the drone's trajectory will be re-recorded instead of continuing to record the original trajectory;

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention can display the trajectory of the drone and the location of the control station in real time when there is a network connection through the network and offline dual-mode processing mechanism, and automatically switch to the offline map and convert the coordinates based on the Mercator projection when there is no network connection. This design significantly improves the flexibility and reliability of drone identification, ensuring that users can continue to monitor the dynamics of drones in complex network environments (such as remote areas or communication interruption scenarios), and expands the coverage of application scenarios. The system supports dual-channel communication of Bluetooth protocol (traditional mode and long-distance mode) and Wi-Fi protocol (NAN mode and Beacon mode), and is compatible with multiple domestic and foreign drone standards. This design greatly improves the versatility of the system, meets the compliance requirements of different countries and regions, promotes cross-platform device interoperability, and reduces user deployment costs.

[0019] Through message segmentation, byte order conversion and dynamic correction rules, the system can quickly parse message package messages and independent messages, and accurately extract drone serial number, longitude and latitude, heading angle, ground speed and control station information. Through preset parsing rules and dynamic flag correction (such as 180-degree compensation for heading angle and adaptive calculation of ground speed multiplier), data decoding errors can be effectively avoided, and the calculation accuracy and real-time performance of location information can be improved. The system converts longitude and latitude data into pixel coordinates of the plane coordinate system, and dynamically scales the offline map with preset resolution, solving the problem of trajectory offset caused by projection error in traditional offline maps. This technology significantly improves the visualization accuracy of drone location marking and historical trajectory in offline scenarios, and enhances users' intuitive understanding of spatial information. By establishing a mapping cache table between drone serial number and historical trajectory, and automatically transferring data to the local database based on preset time periods, the system realizes dynamic management of cache resources. This mechanism reduces memory usage and avoids performance degradation caused by long-term non-update of data. At the same time, it supports rapid backtracking of historical trajectories and optimizes the fluency of user operations. Through independent data receiving modules, parsing engine modules and visualization modules, the system realizes functional decoupling and parallel processing. The modular design facilitates subsequent function upgrades (such as new communication protocol support) or maintenance, reduces the complexity of system iterations, and enhances the commercial application potential of the technical solution. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them: Figure 1 is a flow chart of a method according to an embodiment of the present invention; Figure 2 It is a system modular structure diagram of an embodiment of the present invention. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0022] like Figure 1 As shown in FIG. 1 , an embodiment of the present invention is provided, which provides a method for remotely identifying a drone, including: S1: receiving remote identification data broadcast by a target UAV through a wireless communication protocol, wherein the data includes UAV location information, control station location information, and UAV identification information; The wireless communication protocol includes a Bluetooth protocol and a Wi-Fi protocol, and the target UAV complies with GB 42590-2023, ASTM F3411-22a or ASD-STAN prEN 4709-002 standards.

[0023] Specifically, the step of receiving remote identification data through the Bluetooth protocol includes: When using the Bluetooth Legacy protocol, follow these steps: (a) Establish a continuous listening link on Bluetooth advertising channels 37, 38 and 39; (b) after capturing the broadcast data packet transmitted on the channel, parsing the service data advertisement structure whose AD Type field is 0x16 in the data packet; (c) verifying whether the UUID field in the service data advertisement structure is a preset identifier 0xFFFA; (d) when the UUID field verification passes, intercepting the continuous 25 bytes of data after the UUID field from the service data advertisement structure as the original remote identification message; When using Bluetooth 5.0 and above, follow these steps: (i) Simultaneously monitor Bluetooth basic advertising channels 37, 38, 39 and extended advertising channel group; (ii) parsing the PDU header information in the received broadcast packet and identifying the broadcast indication packet carrying the auxiliary pointer field; (iii) receiving a corresponding auxiliary broadcast packet on a designated extended channel according to the channel mapping index and data offset parameter recorded in the auxiliary pointer field; (iv) Separate the 25-byte original remote identification message from the payload data segment of the auxiliary broadcast packet.

[0024] Specifically, the step of receiving remote identification data through the Wi-Fi protocol includes: (1) When using Wi-Fi NAN mode, follow the steps below: Capture Wi-Fi management frames in the preset working frequency band and filter out messages with a frame type of 0x00 and a subtype of Action; Parse the vendor identification field of the message, verify whether the OUI field value is the preset value 50-6F-9A, and simultaneously check whether the OUI Type field is 0x13; When the field verification passes, decoding and extracting the remote identification payload from the data field of the message according to the format definition of the NAN service discovery frame; (2) When using Wi-Fi Beacon mode, follow the steps below: Continuously listen to management frames on the Wi-Fi basic channel and filter broadcast messages with a frame type of 0x00 and a subtype of Beacon. Parse the vendor specific information element in the broadcast message, verify whether its OUI field value is the preset value FA-0B-BC, and verify whether the vendor type field Vendor Type field is 0x0D; The remote identification payload is separated from the payload content of the information element according to the manufacturer-defined data format.

[0025] Further, S2: parsing the remote identification data, extracting the drone location information, the control station location information and the drone identification information according to the message type field; The steps of parsing the remote identification data include: When a data packet is packaged as a message, the following operations are performed: Read the sub-message length of the first byte and the number of sub-messages of the second byte in the message package message content; Calculate the total length according to the sub-message length and the number of sub-messages, and intercept the corresponding byte stream; Splitting the byte stream into multiple sub-messages according to a preset byte length; For each sub-message, the corresponding parsing rule is called according to its message type field for decoding; When the data packet is an independent message, decoding is performed directly according to the message type field of the independent message matching the preset parsing rule.

[0026] Specifically, the message type includes at least one of the following: Parse the basic ID message to extract the drone serial number and drone type, where the drone type is an enumeration type with a value range of 0-15; Parse the position vector message to extract the longitude, latitude, ground speed and heading angle of the drone, where: the heading angle is dynamically corrected based on the E / W direction flag bit. When the flag bit is 1, the heading angle calculation value increases by 180 degrees; the ground speed is decoded according to the speed multiplier flag bit. If the flag bit is 1, the ground speed = the encoded value × the first preset coefficient, otherwise the ground speed = the encoded value × the second preset coefficient + the third preset coefficient; the vertical speed is converted into floating-point data by multiplying the encoded value by the fourth preset coefficient; The system message is parsed to extract the control station location type and the operating area radius, wherein: the control station location type includes a take-off point, a dynamic control station or a fixed control station; the operating area radius generates an actual physical distance value by multiplying the coded value by a distance conversion coefficient.

[0027] Specifically, the analysis of the longitude and latitude of the drone includes: Reverse the byte order of the longitude and latitude fields encoded in little endian order to generate 32-bit signed integer data with the high-order byte first and the low-order byte last; The 32-bit signed integer data are divided by the preset scaling factor to obtain double-precision floating-point longitude coordinates and latitude coordinates.

[0028] In this embodiment, the remote identification information consists of two parts: a header and a message content, and the header is the first byte of the message.

[0029] The first 4 bits in the header are the message type, and the last 4 bits are the interface version. The focus should be on the message type of the first 4 bits, and the data in the message content should be parsed based on the message type.

[0030] The value range of the message type field is 0x0-0xF.

[0031] When the message type field value is 0x0, it indicates that the message is a Basic ID message.

[0032] When the message type field value is 0x1, it indicates that the message is a location vector message (Location / Vector message).

[0033] When the message type field value is 0x2, it indicates that the message is an authentication message (Authentication message).

[0034] When the message type field value is 0x3, it indicates that the message is a running description message (Self-ID message).

[0035] When the message type field value is 0x4, it indicates that the message is a system message.

[0036] When the message type field value is 0x5, it indicates that the message is an operator ID message (Operator ID message).

[0037] When the message type field value is 0xF, it indicates that the message is a message pack message.

[0038] It should be noted that when the message type is a non-packed message, the header + message content is a total of 25 bytes, including one byte for the header and 24 bytes for the message content.

[0039] When the message type field value is 0xF (that is, when the message is packaged), it means that the message is packaged by multiple messages whose message type fields are 0x0-0x5. Its length is 3+N*25 bytes, where N is the number of packaged messages.

[0040] When the message type field is 0xF (packed message), its structure is: The first byte of the message content is the length of each message in the packaged message.

[0041] The second byte of the message content is the number of messages contained in the packed message.

[0042] The N*25 bytes starting from the third byte of the message content are multiple packed messages whose message type fields are 0x0-0x5.

[0043] When the message type field is 0xF (packed message), the decoding method is: Directly convert the length of each message into decimal, multiply it by the decimal number of messages, and calculate the total length of the messages.

[0044] Bytes are intercepted based on the total length of the message, and the intercepted bytes are divided according to the number of messages. The specific messages divided are decoded using the corresponding decoding method. If little-endian data is encountered during decoding, the encoded bytes will be flipped before the decoding operation.

[0045] When the message type field is 0x0 (Basic ID message), its structure is: The first byte of the message content consists of two fields, the first 4 bits are the ID type field, and the last 4 bits are the drone type field. The 20 bytes starting from the second byte of the message content are the drone serial number field. The 3 bytes starting from the 22nd byte of the message content are reserved.

[0046] When the message type field is 0x0 (basic ID message), the decoding method is: The first 4 bits of the ID type field are enumerated types. When the field value is 0x1, it indicates that the ID type is a serial number. When the field value is 0x2, it indicates that the ID type is a registration ID assigned by CAA. When the ID type is 0x3, it indicates that the ID type is a UUID assigned by UTM. When the ID type is 0x4, it indicates a specific session ID.

[0047] The drone type field is also an enumeration type: When the value is 0, it means the drone is None / Not Declared.

[0048] When the value is 1, it means that the drone is a fixed-wing aircraft (Aeroplane).

[0049] When the value is 2, it means that the drone is a helicopter (or multirotor).

[0050] When the value is 3, it means the drone is a gyroplane.

[0051] When the value is 4, it means that the drone is a HybridLift (Fixed wing aircraft that can take off vertically).

[0052] When the value is 5, it means the drone is an ornithopter.

[0053] When the value is 6, it means the drone is a glider.

[0054] When the value is 7, it means the drone is a kite.

[0055] When the value is 8, it means the drone is a free balloon.

[0056] When the value is 9, it means the drone is a captive balloon.

[0057] When the value is 10, it means the drone is an airship (such as an ablimp).

[0058] When the value is 11, it means the drone is in free fall / parachute (unpowered).

[0059] When the value is 12, it means the drone is a rocket.

[0060] When the value is 13, it means the drone is a tethered powered aircraft.

[0061] When the value is 14, it means the drone is a ground obstacle.

[0062] When the value is 15, it means the drone is Other.

[0063] The serial number field will be directly ASCII decoded to get the specific drone ID.

[0064] The message type field is 0x1 (position vector message) and its structure is: The first byte of the message content is divided into the first 4 bits of the operation status field and the last 4 bits of the flag field, where the first flag bit is a reserved flag bit, the second bit is the altitude type bit, the third bit is the track angle E / W direction flag bit, and the fourth bit is the speed multiplier bit.

[0065] The third byte of the message content is the track angle field. The track angle refers to the angle between the flight track of the aircraft and the true north direction of the ground during its movement in the air.

[0066] The third byte of the message content is the ground speed field.

[0067] The fourth byte of the message content is the vertical speed field. The speed is positive when climbing and negative when descending.

[0068] The 4 bytes starting from the 5th byte of the message content are the latitude field.

[0069] The 4 bytes starting from the 9th byte of the message content are the longitude field.

[0070] The 2 bytes starting from the 13th byte of the message content are the pressure altitude field.

[0071] The 2 bytes starting from the 15th byte of the message content are the geometry height field.

[0072] The 2 bytes starting from the 17th byte of the message content are the height from the ground field.

[0073] The first 4 bits of the 19th byte of the message content are the horizontal precision field, and the last 4 bits are the vertical precision field.

[0074] The first 4 bits of the 20th byte of the message content are the pressure altitude accuracy field, and the last 4 bits are the speed accuracy field.

[0075] The 2 bytes starting from the 21st byte of the message content are the timestamp field.

[0076] The 23rd byte of the message content is the timestamp precision field.

[0077] The 24th byte of the message content is reserved.

[0078] The message type field is 0x1 (position vector message), which is decoded as: The operating status field is an enumeration value. When the value is 0, it means that the operating status of the drone is Undeclared. When the value is 1, it means that the operating status of the drone is Ground. When the value is 2, it means that the operating status of the drone is Airborne. When the value is 3, it means that the operating status of the drone is Emergency. When the value is 4, it means that the operating status of the drone is Remote ID System Failure. Values ​​5-15 are reserved.

[0079] Each flag bit in the flag bit field is used for decoding in conjunction with subsequent data.

[0080] The track angle field is an unsigned integer (Unsigned Int), and the encoded value range is 0-179. When the track angle E / W direction flag is 1, the decoded value should be the decimal value of the field + 180, otherwise the decimal value of the field is directly taken.

[0081] The ground speed field is encoded as an unsigned integer (Unsigned Int). When decoding, first query the ground speed multiplier flag. When it is 1, the decoded value = encoded value * 0.25; when it is 0, the decoded value = (encoded value * 0.75) + (255 * 0.25). If the value is decoded to 255, it means an unknown value; if the value is decoded to 254.25, the speed is at least 254.25.

[0082] The vertical speed field is encoded as an 8-bit integer (Int8). When decoding, the integer value is directly multiplied by 0.5 and then converted to a floating point type (Float).

[0083] The latitude field is encoded as a little-endian 32-bit integer (Int32). When decoding, the encoded value is divided by 10^7 and then converted to a double-precision floating point type (Double).

[0084] The longitude field is encoded as a little-endian 32-bit integer (Int32). When decoding, the encoded value is divided by 10^7 and then converted to a double-precision floating point type (Double).

[0085] The pressure altitude is encoded as a little-endian 16-bit unsigned integer (Unsigned Int16). When decoding, the encoded value is * 0.5-1000.

[0086] The geometric height is encoded as a little-endian 16-bit unsigned integer (Unsigned Int16). When decoding, the encoded value is * 0.5-1000.

[0087] The height above the ground is encoded as a little-endian 16-bit unsigned integer (Unsigned Int16). When decoding, the encoded value is * 0.5-1000.

[0088] The horizontal precision is an enumeration type: When the value is 0, it means the horizontal accuracy is ≥18.52 km (10 NM) or unknown.

[0089] When the value is 1, it means the horizontal accuracy is <18.52 km (10 NM).

[0090] When the value is 2, it means the horizontal accuracy is <7.408 km (4 NM).

[0091] When the value is 3, it means the horizontal accuracy is <3.704 km (2 NM).

[0092] When the value is 4, it means the horizontal accuracy is <1852 m (1 NM).

[0093] When the value is 5, it means the horizontal accuracy is <926 m (0.5 NM).

[0094] When the value is 6, it means the horizontal accuracy is <555.6 m (0.3 NM).

[0095] When the value is 7, it means the horizontal accuracy is <185.2 m (0.1 NM).

[0096] When the value is 8, it means the horizontal accuracy is <92.6 m (0.05 NM).

[0097] When the value is 9, it means the horizontal accuracy is <30 m.

[0098] When the value is 10, it means the horizontal accuracy is <10 m.

[0099] When the value is 11, it means the horizontal accuracy is <3 m.

[0100] When the value is 12, it means the horizontal accuracy is <1 m.

[0101] When the value is 13 to 15, these values ​​are reserved.

[0102] Vertical precision is an enumeration type: When the value is 0, it means the vertical accuracy is greater than or equal to 150 meters or unknown.

[0103] When the value is 1, it means the vertical accuracy is less than 45 meters.

[0104] When the value is 2, it means the vertical accuracy is less than 25 meters.

[0105] When the value is 3, it means the vertical accuracy is less than 10 meters.

[0106] When the value is 4, it means the vertical accuracy is less than 3 meters.

[0107] When the value is 5, it means the vertical accuracy is less than 1 meter.

[0108] When the value is 6 to 15, it means that the vertical accuracy is a reserved value.

[0109] The barometric altitude accuracy is an enumeration type: When the value is 0, it means the vertical accuracy is greater than or equal to 150 meters or unknown.

[0110] When the value is 1, it means the vertical accuracy is less than 45 meters.

[0111] When the value is 2, it means the vertical accuracy is less than 25 meters.

[0112] When the value is 3, it means the vertical accuracy is less than 10 meters.

[0113] When the value is 4, it means the vertical accuracy is less than 3 meters.

[0114] When the value is 5, it means the vertical accuracy is less than 1 meter.

[0115] When the value is 6 to 15, it means that the vertical accuracy is a reserved value.

[0116] Speed ​​accuracy is an enumeration type: When the value is 0, the velocity accuracy is ≥10 m / s or unknown; When the value is 1, the speed accuracy is <10 m / s; When the value is 2, the speed accuracy is <3 m / s; When the value is 3, the speed accuracy is <1 m / s; When the value is 4, the speed accuracy is <0.3 m / s; When the value is 5 to 15, these values ​​are reserved.

[0117] The timestamp is encoded as a little-endian unsigned integer (Unsigned Int), representing the number of seconds since the last hour, accurate to one decimal place. For example, when the value is 3611, the decoded value is 6 minutes and 1.1 seconds since the last hour.

[0118] Every increase of 1 in the timestamp precision encoding value indicates an increase of 0.1 seconds in precision. The encoding value ranges from 0 to 15, and the decoding value ranges from 0.1 seconds to 1.5 seconds. 0 indicates unknown. For example, an encoding value of 3 indicates a timestamp precision of 0.3 seconds.

[0119] The message type field is 0x2 (authentication message), and its structure is: The authentication message is sent in pages, so the structure of page 0 and subsequent pages is different.

[0120] Page zero is structured as follows: The 1st to 4th bits of the first byte of the message content are the authentication type field, and the 5th to 8th bits are the page number field. The page number of the first page must be 0.

[0121] Bits 1-4 of the second byte of the message content are reserved, and bits 5-8 are the page number of the last page, starting from 0.

[0122] The third byte of the message is the length field of the authentication data, in bytes.

[0123] The 4 bytes starting from the 4th byte of the message are the timestamp field.

[0124] The 8th byte to the last 17 bytes of the message are authentication data.

[0125] The structure of the following pages 1 to 15 is as follows: The first byte of the message content has bits 1-4 as the authentication type field, and bits 5-8 as the page number field.

[0126] The second byte to the last 23 bytes of the message are authentication data.

[0127] The message type field is 0x2 (authentication message), and its decoding method is: Before decoding the authentication message, we must understand that the authentication data / signature field is considered opaque data by the standard. When receiving, it is necessary to understand how to interpret and verify this data according to the authentication type and pre-agreed specifications. Therefore, when receiving the signature field of an unknown drone, it will not be possible to parse the specific content of the authentication information sent by the drone, but only to parse out what type of authentication information the drone sent.

[0128] The decoding method of the authentication message on page 0 is: The authentication type field is an enumeration type: When the value is 0, it means the authentication type is "none".

[0129] When the value is 1, it means the authentication type is "UAS ID Signature".

[0130] When the value is 2, it means the authentication type is "Operator ID Signature".

[0131] When the value is 3, it means the authentication type is "message set signature".

[0132] When the value is 4, it means the authentication type is "authentication provided by network remote ID".

[0133] When the value is 5, it means the authentication type is "specific authentication method".

[0134] When the value is 6 to 9, it is a reserved value.

[0135] When the value is A to F, it means the authentication type is "for private use".

[0136] The page number field is decoded by directly converting binary to decimal.

[0137] The page number field of the last page is decoded by directly converting binary to decimal.

[0138] The length field is decoded by directly converting binary to decimal.

[0139] The timestamp field is a 32-bit Unix timestamp (UTC) in seconds since 00:00:00 on January 1, 2019. When decoded, it is converted to a standard timestamp by adding 1546300800 to the timestamp encoding value.

[0140] If there is authentication data on page 0 and the page number of the last page is not 0, the authentication data on page 0 will be temporarily stored and displayed after subsequent data is spliced. If there is authentication data on page 0 and the page number of the last page is 0, the original bytes of the data will be displayed directly. If there is no authentication data on page 0, the authentication data field will be displayed as a null value (NULL).

[0141] The decoding method of the authentication message on page 1-15 is: The authentication type field is an enumeration type: When the value is 0, it means the authentication type is "none".

[0142] When the value is 1, it means the authentication type is "UAS ID Signature".

[0143] When the value is 2, it means the authentication type is "Operator ID Signature".

[0144] When the value is 3, it means the authentication type is "message set signature".

[0145] When the value is 4, it means the authentication type is "authentication provided by network remote ID".

[0146] When the value is 5, it means the authentication type is "specific authentication method".

[0147] When the value is 6 to 9, it is a reserved value.

[0148] When the value is A to F, it means the authentication type is "for private use".

[0149] The page number field is decoded by directly converting binary to decimal.

[0150] The authentication data will be concatenated with the previous authentication data on this page and displayed in raw bytes.

[0151] The message type field is 0x3 (operation description message), and its decoding method is: The first byte of the message content is the description type field.

[0152] The 23 bytes from the second byte to the last of the message content are the specific description field.

[0153] The message type field is 0x3 (operation description message, which is decoded as follows: The description type is an enumeration type: When the value is 0, it means that the description message is a text description.

[0154] When the value is 1, it means that the description message is an emergency description.

[0155] When the value is 2, it means that the description message is an extended status description.

[0156] When the value is 3-200, it is a reserved value.

[0157] When the value is 201-255, it is for private use.

[0158] The specific description field is ASCII-encoded and is decoded according to the ASCII code table.

[0159] The message type field is 0x4 (system message), and its structure is: The first byte of the message content is the flag bit, which has two fields: bits 1-3 are the reserved part, bits 4-6 are the level classification field, and bits 7-8 are the control station location type field.

[0160] The 4 bytes starting from the 2nd byte of the message content are the latitude field of the UAV control station.

[0161] The 4 bytes starting from the 6th byte of the message content are the longitude field of the drone control station.

[0162] The 2 bytes starting from the 10th byte of the message content are the operation area count field, which contains the number of aircraft in the operation area.

[0163] The 12th byte of the message content is the operating area radius field.

[0164] The 2 bytes starting from the 13th byte of the message content are the area height upper limit field.

[0165] The 2 bytes starting from the 15th byte of the message content are the area height lower limit field.

[0166] The 17th byte of the message content contains two fields, the drone operation category field of 1-4 bits and the drone level field of 5-8 bits.

[0167] The 2 bytes starting from the 18th byte of the message content are the UAV control station altitude field.

[0168] The 4 bytes starting from the 20th byte of the message content are the timestamp field.

[0169] The 24th byte of the message content is the reserved part.

[0170] The message type field is 0x4 (system message), which is decoded as follows: The level classification region field is an enumeration type: When the value is 0, it means undefined.

[0171] When the value is 1, it indicates the European Union.

[0172] When the value is 2, it means China.

[0173] Values ​​3-7 are reserved.

[0174] The control station location field is an enumeration type: When the value is 0, it means takeoff.

[0175] When the value is 1, it indicates dynamic.

[0176] When the value is 2, it means fixed.

[0177] The control station latitude field is encoded as a little-endian 32-bit integer (Int32). When decoding, the encoded value is divided by 10^7 and then converted to a double-precision floating point type (Double).

[0178] The control station longitude field is encoded as a little-endian 32-bit integer (Int32). When decoding, the encoded value is divided by 10^7 and then converted to a double-precision floating point type (Double).

[0179] The region count field is in little-endian order, with a default value of 1, and is directly converted to decimal when decoding.

[0180] When decoding the area radius field, the encoded value will be multiplied by 10, and the unit is meters.

[0181] The upper limit of the area height is encoded as a little-endian 16-bit unsigned integer (Unsigned Int16). When decoding, the encoded value is * 0.5-1000.

[0182] The lower limit of the area height is encoded as a little-endian 16-bit unsigned integer (Unsigned Int16). When decoding, the encoded value is * 0.5-1000.

[0183] The drone operation category field is an enumeration type: When the value is 0, it indicates an undefined type.

[0184] When the value is 1, it indicates the development class.

[0185] When the value is 2, it indicates the privileged category.

[0186] When the value is 3, it indicates the approval category.

[0187] Values ​​4-15 are reserved.

[0188] The drone level field is an enumeration type: 0 = Micro unmanned aerial vehicle When the value is 1, it indicates a light unmanned aerial vehicle.

[0189] When the value is 2, it indicates a small unmanned aerial vehicle.

[0190] When the value is 3, it indicates other unmanned aerial vehicles with operational identification capabilities.

[0191] Values ​​4-15 are reserved.

[0192] The control station height is encoded as a little-endian 16-bit unsigned integer (Unsigned Int16). When decoding, the encoded value is * 0.5-1000.

[0193] The timestamp field is a 32-bit Unix timestamp (UTC) in seconds since 00:00:00 on January 1, 2019. When decoded, it is converted to a standard timestamp by adding 1546300800 to the timestamp encoding value.

[0194] When the message type field is 0x5 (Operator ID message), its structure is: The first byte of the message content is the operator ID type.

[0195] The 20 bytes starting from the second byte of the message content are the operator ID.

[0196] The message content starting from the 22nd byte to the last 3 bytes is the reserved part.

[0197] When the message type field is 0x5 (operator ID message), the decoding method is: The operator ID type is an enumeration type: When the value is 0, it indicates the type is operator ID.

[0198] Values ​​1-200 are reserved.

[0199] The value 201-255 is a user-defined value.

[0200] The operator ID field is decoded directly through ASCII code.

[0201] When the message is decoded according to the rules, the decoded data will be displayed visually, where the longitude and latitude of the drone and the control station will be displayed on the map, and the trajectory of the drone will be drawn based on the longitude and latitude information of the drone received last time. The rest of the information will be displayed directly in text.

[0202] Further, S3: in the network connection state, the map interface is called to display the drone trajectory and control station location in real time; S4: In a state without network connection, the location information is converted into a plane coordinate system, and a location mark and a historical track are generated in an offline map.

[0203] Specifically, the transformation of the plane coordinate system is based on the Mercator projection rule, which specifically includes: Convert the units of the longitude λ and latitude φ of the drone from degrees to radians, and the calculation formula is: ; in: is the longitude of the drone, in degrees; is the latitude of the drone, in degrees; is the pi constant; is the arc value of the drone's longitude; is the arc value of the drone's latitude; Calculate the plane coordinates x and y based on the Mercator projection rules: ; in: is the east-west coordinate; is the north-south coordinate; R is the equatorial radius of the earth, which is 6378137 meters; In this embodiment, after obtaining the Mercator coordinates, the next step is to display the coordinates on an offline map. Considering the limited offline storage space, the map resolution r is set to 100 meters per pixel in this embodiment. The resolution can be adjusted according to actual conditions to adjust the projection accuracy.

[0204] According to the preset resolution r, the plane coordinates are converted to pixel coordinates: ; in: , is the pixel coordinate on the map; The map display resolution is used to control the coordinate scaling.

[0205] In this embodiment, after the pixel coordinates are converted, the pixel points corresponding to each longitude and latitude coordinate and the lines between the points can be drawn on the map to display the position and trajectory.

[0206] After decoding and displaying the received message, we will continue to monitor the subsequent messages to see if there are any messages with the same sequence number as the previous message: If yes, unpack the subsequent messages with the same sequence number and update the previous display; If not, a new display interface will be created and displayed separately from the previous interface.

[0207] At the same time, the interval time from the last time a message containing the sequence number was received will be continuously determined. If no message containing the sequence number is received within ten minutes of the specified time, the message containing the sequence number will be archived. When a message containing the sequence number is received again, recording will be restarted.

[0208] The offline map display step includes: Establishing a mapping cache table between drone serial numbers and historical trajectories, wherein the cache table uses a key-value pair structure to store pixel coordinate historical data associated with drone serial numbers; When it is detected that a drone with a certain serial number has not updated data within a preset time period, the historical trajectory data is transferred to the local database and the corresponding cache resources are released.

[0209] like Figure 2 FIG. 1 is another embodiment of the present invention, which provides a remote identification system for unmanned aerial vehicles, including: The data receiving module comprises: a Bluetooth receiving unit configured to monitor channels 37, 38, and 39 in Bluetooth traditional mode and to parse the auxiliary pointer field to locate auxiliary advertising packets in Bluetooth 5.0 and above long-range mode; The Wi-Fi receiving unit is configured to filter management frames with an OUI value of 50-6F-9A in NAN mode and extract payload data in a vendor-specific information element format in Beacon mode; Parsing engine modules, including: A message segmentation unit configured to segment the message package message into byte streams according to the length and number of sub-messages; a byte order conversion unit configured to perform little endian to host order conversion on the latitude, longitude, altitude, and timestamp fields; Visualization module, including: An online rendering unit is configured to call a map service interface to dynamically display the trajectory of the drone and the location of the control station, and load corresponding icons according to the type of drone; Offline rendering unit, configured to generate static maps based on Mercator projection, and support caching and archiving of historical trajectory data.

[0210] In summary, the present invention solves the technical pain points of existing UAV remote identification technologies, such as strong network dependence, insufficient standard coverage, large decoding errors, and low offline map accuracy, through multi-protocol compatibility, dynamic network adaptation, high-precision data analysis, and resource optimization design. It significantly improves the real-time, reliability, and user experience of UAV supervision, and has a wide range of application value. In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are contradictory.

[0211] Any process or method description in the flow chart or otherwise described herein can be understood to represent a module, fragment or portion of a code including one or more executable instructions for implementing the steps of a specific logical function or process. And the scope of the preferred embodiment of the present application includes other implementations, in which the functions may not be performed in the order shown or discussed, including in a substantially simultaneous manner or in a reverse order according to the functions involved.

[0212] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of various changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for remote identification of unmanned aerial vehicles, characterized in that: include: Receive remote identification data broadcast by the target UAV through a wireless communication protocol, wherein the remote identification data includes UAV location information, control station location information, and UAV identification information; Parsing the remote identification data, extracting drone location information, control station location information and drone identification information according to the message type field; When connected to the network, call the map interface to display the drone trajectory and control station location in real time; In a state without network connection, the drone position information is converted into a plane coordinate system, and a position mark and a historical track are generated in an offline map.

2. The method for remotely identifying a drone according to claim 1, characterized in that: The wireless communication protocol includes a Bluetooth protocol and a Wi-Fi protocol, and the target UAV complies with GB 42590-2023, ASTM F3411-22a or ASD-STANprEN 4709-002 standards.

3. The method for remotely identifying a drone according to claim 2, characterized in that: The step of receiving remote identification data via the Bluetooth protocol comprises: When using the Bluetooth Legacy protocol, follow these steps: (a) Establish a continuous listening link on Bluetooth advertising channels 37, 38 and 39; (b) after capturing the broadcast data packet transmitted on the channel, parsing the service data advertisement structure whose AD Type field is 0x16 in the data packet; (c) verifying whether the UUID field in the service data advertisement structure is a preset identifier 0xFFFA; (d) when the UUID field verification passes, intercepting the continuous 25 bytes of data after the UUID field from the service data advertisement structure as the original remote identification message; When using Bluetooth 5.0 and above, follow these steps: (i) Simultaneously monitor Bluetooth basic advertising channels 37, 38, 39 and extended advertising channel group; (ii) parsing the PDU header information in the received broadcast packet and identifying the broadcast indication packet carrying the auxiliary pointer field; (iii) receiving a corresponding auxiliary broadcast packet on a designated extended channel according to the channel mapping index and data offset parameter recorded in the auxiliary pointer field; (iv) Separate the 25-byte original remote identification message from the payload data segment of the auxiliary broadcast packet.

4. The method for remotely identifying a drone according to claim 2, characterized in that: The steps of receiving remote identification data via the Wi-Fi protocol include: (1) When using Wi-Fi NAN mode, follow the steps below: Capture Wi-Fi management frames in the preset working frequency band and filter out messages with a frame type of 0x00 and a subtype of Action; Parse the vendor identification field of the message, verify whether the OUI field value is the preset value 50-6F-9A, and simultaneously check whether the OUI Type field is 0x13; When the field verification passes, decoding and extracting the remote identification payload from the data field of the message according to the format definition of the NAN service discovery frame; (2) When using Wi-Fi Beacon mode, follow the steps below: Continuously listen to management frames on the Wi-Fi basic channel and filter broadcast messages with a frame type of 0x00 and a subtype of Beacon. Parse the vendor specific information element in the broadcast message, verify whether its OUI field value is the preset value FA-0B-BC, and verify whether the vendor type field Vendor Type field is 0x0D; The remote identification payload is separated from the payload content of the information element according to the manufacturer-defined data format.

5. The method for remotely identifying a drone according to claim 1, characterized in that: Parsing the remote identification data, the steps are as follows: When a data packet is packaged as a message, the following operations are performed: Read the sub-message length of the first byte and the number of sub-messages of the second byte in the message package message content; Calculate the total length according to the sub-message length and the number of sub-messages, and intercept the corresponding byte stream; Splitting the byte stream into multiple sub-messages according to a preset byte length; For each sub-message, the corresponding parsing rule is called according to its message type field for decoding; When the data packet is an independent message, decoding is performed directly according to the message type field of the independent message matching the preset parsing rule.

6. The method for remotely identifying a drone according to claim 5, characterized in that: The message types include: Parse the basic ID message to extract the drone serial number and drone type, where the drone type is an enumeration type with a value range of 0-15; Parse the position vector message to extract the longitude, latitude, ground speed and heading angle of the drone, where: the heading angle is dynamically corrected based on the E / W direction flag bit. When the flag bit is 1, the heading angle calculation value increases by 180 degrees; the ground speed is decoded according to the speed multiplier flag bit. If the flag bit is 1, the ground speed = the encoded value × the first preset coefficient, otherwise the ground speed = the encoded value × the second preset coefficient + the third preset coefficient; the vertical speed is converted into floating-point data by multiplying the encoded value by the fourth preset coefficient; The system message is parsed to extract the control station location type and the operating area radius, wherein: the control station location type includes a take-off point, a dynamic control station or a fixed control station; the operating area radius generates an actual physical distance value by multiplying the coded value by a distance conversion coefficient.

7. The method for remotely identifying a drone according to claim 6, characterized in that: The analysis of the longitude and latitude of the drone includes: Reverse the byte order of the longitude and latitude fields encoded in little endian order to generate 32-bit signed integer data with the high-order byte first and the low-order byte last; The 32-bit signed integer data is divided by the preset scaling factor to obtain double-precision floating-point longitude and latitude coordinates.

8. The method for remotely identifying a drone according to claim 1, characterized in that: The transformation of the plane coordinate system is based on the Mercator projection rule, which specifically includes: Convert the units of the longitude λ and latitude φ of the drone from degrees to radians, and the calculation formula is: ; in: is the longitude of the drone, in degrees; is the latitude of the drone, in degrees; is the pi constant; is the arc value of the drone's longitude; is the arc value of the drone's latitude; Calculate the plane coordinates x and y based on the Mercator projection rules: ; in: is the east-west coordinate; is the north-south coordinate; R is the equatorial radius of the earth; According to the preset resolution r, the plane coordinates are converted to pixel coordinates: ； in: , is the pixel coordinate on the map; Display resolution for the map.

9. The method for remotely identifying a drone according to claim 1, characterized in that: The display of the offline map is achieved by the following steps: Establishing a mapping cache table between drone serial numbers and historical trajectories, wherein the mapping cache table uses a key-value pair structure to store pixel coordinate historical data associated with drone serial numbers; When it is detected that a drone with a certain serial number has not updated its data within a preset time period, the historical trajectory data will be transferred to the local database and the corresponding cache resources will be released.

10. An identification system for a remote identification method of a drone according to any one of claims 1 to 9, characterized in that: include: The data receiving module comprises: A Bluetooth receiving unit for monitoring channels 37, 38, and 39 in Bluetooth traditional mode and parsing auxiliary pointer fields to locate auxiliary advertising packets in Bluetooth 5.0 and above long-range mode; The Wi-Fi receiving unit is used to filter the management frames with OUI value 50-6F-9A in NAN mode and extract the payload data in the vendor-specific information element format in Beacon mode; Parsing engine modules, including: A message segmentation unit, which segments the message package message into byte streams according to the length and number of sub-messages; Byte order conversion unit, which performs little endian to host order conversion on latitude, longitude, altitude and timestamp fields; Visualization module, including: The online rendering unit calls the map service interface to dynamically display the drone trajectory and control station location, and loads the corresponding icon according to the drone type; The offline rendering unit generates static maps based on the Mercator projection and supports caching and archiving of historical trajectory data.

Images