An unmanned aerial vehicle search system and method of operation using active electronic tag technology

Abstract

The application discloses an unmanned aerial vehicle searching system using active electronic tag technology and a working method.The system uses LDSW long-distance low-power wireless sleep wake-up technology, and the mobility and high-altitude position of the unmanned aerial vehicle to realize a farther communication distance and a larger searching range of the active electronic tag.The unmanned aerial vehicle originally used for video shooting and simple transportation becomes a multifunctional unmanned aerial vehicle which can be used for personnel and material searching, sensor data collection, various material counting and wireless communication relay, etc., so that the application range and market of the unmanned aerial vehicle are greatly expanded.Especially in remote areas without network and electricity, the information collection of hydrogeological and disaster monitoring sensors and the automatic inspection of the working states of various facilities and buildings are realized.The application also links the identification and positioning of the target with the video shooting, and uses the intermittent working mode to reduce the power consumption of the unmanned aerial vehicle, and increase the cruising time and range of the unmanned aerial vehicle.

Description

Technical Field

[0001] This invention relates to the field of wireless communication technology, and in particular to a drone search system and operating method using active electronic tag technology. Background Technology

[0002] Despite the increasingly widespread use of drones, the current functionality of civilian drones is mainly limited to video recording and simple material transportation. Search and rescue operations and equipment inspections, such as high-voltage power line inspections, still rely primarily on manual video observation, resulting in very low efficiency. This is due to the lack of a low-power wireless long-range sleep / wake technology, especially a unified technical standard for it.

[0003] Furthermore, the cruising and remote control distances of drones are related to the wireless communication technology they employ. For example, image transmission often requires high-frequency broadband technology, utilizing 2.4GHz and 5.8GHz communication frequencies to meet the high-speed requirements of image transmission. At the same time, using high communication rates and frequencies often affects the drone's remote control range and cruising distance. Therefore, reducing unnecessary image transmission and employing targeted image capture and transmission becomes crucial. How to achieve longer remote control distances using lower communication frequencies and / or lower communication rates is clearly very important. Summary of the Invention

[0004] In view of this, the present invention provides a drone search system and operating method using active electronic tag technology, aiming to solve the above-mentioned technical problems.

[0005] To address the above technical problems, the present invention provides a drone search system using active electronic tags, comprising a remotely controllable drone, a remote wireless controller for controlling the drone, an onboard active electronic tag reader / writer, and at least one active electronic tag carried by the target being searched. The drone includes a GPS satellite positioning unit, an onboard information management unit, and an onboard communication unit that communicates with the remote wireless controller. Each active electronic tag and the active electronic tag reader / writer possesses a unique identification code. The active electronic tag employs a low duty cycle operating mode with periodic sleep and brief periods of operation upon waking, and is connected to one or more IoT terminals. The IoT terminals include, but are not limited to, sensors, controllers, and GPS devices. The active electronic tag is also used to control the operation of the IoT terminal. When the drone approaches the target via mobile search and enters the communication range between the onboard active electronic tag reader and the active electronic tag carried by the target, wireless communication will be established between the onboard active electronic tag reader and the electronic tag, and information will be exchanged. The exchanged information includes the GPS location coordinates of the target, sensor information, short voice information, or other digital information related to the target. The onboard active electronic tag reader stores the information about the target it obtains through the information exchange in the onboard active electronic tag reader or transmits it wirelessly to the drone manager.

[0006] In one implementation, the communication between the active electronic tag and the airborne active electronic tag reader employs a periodic sleep mode, including a low-power operating state for a brief moment after waking up and listening for signals from the airborne electronic tag reader on a pre-set wireless channel. The listening signal is determined by whether the electronic tag receives an RF signal with some or all of the radio frequency characteristics required for wireless communication between the two parties, including communication frequency, modulation method, and encoding method, or receives a data packet, including a complete data packet or an incomplete special data packet. If the electronic tag receives only an RF signal meeting the above conditions at the moment of listening, it will extend the listening time to receive a complete wireless digital signal packet. After receiving the data packet, the electronic tag will parse it according to the communication protocol requirements. If the electronic tag does not receive an RF signal or data packet meeting the above conditions at the moment of listening, it will immediately return to the low-power state at the moment of waking up from periodic sleep.

[0007] As an implementation, when the on-board active electronic tag reader-writer communicates with the active electronic tag in a single-channel communication mode, the on-board active electronic tag reader-writer will adopt a time-division method. That is, within a TD time period greater than the sleep-wake cycle SWC of the electronic tag, it continuously and repeatedly broadcasts information to the active electronic tag without interruption, and within a RT time period (RT > TD) after the end of the broadcast, it enters the state of receiving information returned by the active electronic tag in a CSMA manner; and so on until the relevant information transmitted by the searched target is obtained; where the length of RT depends on the time required for the transmission of the relevant information; the entire process of the on-board active electronic tag reader-writer broadcasting information within the TD time and then receiving information within the RT time can be intermittent, and its time interval PT is determined after considering the flight speed U of the UAV, the communication between the active electronic tag reader-writer and the active electronic tag, the signal coverage length range L in the flight direction of the UAV, and the magnitudes of the TD and RT values, so as to ensure that the reader-writer can complete the required information interaction with the electronic tags within the search range, and PT at least satisfies the relationship PT < L / U - (TD + RT).

[0008] As an implementation, when the on-board active electronic tag reader-writer communicates with the active electronic tag in a multi-channel communication mode, the on-board active electronic tag reader-writer will arrange a dedicated channel. Within a TD time period greater than the sleep-wake cycle SWC of the electronic tag, while continuously and repeatedly broadcasting information to the active electronic tag without interruption, it also receives information returned by the active electronic tag in a CSMA manner within the RT time period on another or multiple pre-arranged or temporarily arranged channels in the information broadcast by the active electronic tag reader-writer; the process of the active on-board electronic tag reader-writer broadcasting information within the TD time and receiving information within the matching RT time is carried out simultaneously (RT > TD), and these two simultaneous processes can be intermittent or continuous without interruption; after receiving the broadcast information of the reader-writer on the dedicated channel, the active electronic tag will immediately jump to another or multiple communication channels according to the pre-arrangement or the arrangement in the information broadcast by the reader-writer and return information to the reader-writer in a CSMA manner.

[0009] As an implementation, it further includes at least one on-board camera; the on-board camera is used for targeted imaging after the searched target is located, and at this time, the communication channel for transmitting the imaging video includes but is not limited to using the flight remote control communication channel of the UAV.

[0010] As one implementation method, when the information transmitted by the searched target to the airborne reader needs to be collected by the searched target for a long time, if the collection time exceeds the time that the UAV is within the communication range between the airborne active electronic tag reader and the ground electronic tag, the information will be replaced with the latest information that is pre-stored in the active electronic tag connected to it.

[0011] In one implementation, the information of the searched target is transmitted wirelessly to the drone manager, including through direct wireless communication between the airborne active electronic tag reader and the drone remote controller; or the airborne active electronic tag reader first transmits the information to the airborne communication unit via a wired connection, and then transmits it to the drone manager through wireless communication between the airborne communication unit and the drone remote controller; or through a mobile network communication terminal and a mobile communication network wired to the airborne electronic tag reader; or through a BeiDou short message module and a BeiDou satellite communication system wired to the airborne reader.

[0012] In one implementation, the UAV onboard communication unit and the onboard active electronic tag reader share the same wireless radio frequency transceiver. The shared wireless transceiver undertakes two different communication tasks: communication with the electronic tag and communication with the UAV remote controller, using a time-division or time-division plus frequency-division working mode.

[0013] Accordingly, the present invention also provides a drone search method using active electronic tag technology, applied to the aforementioned drone search system using active electronic tag technology, comprising:

[0014] An active RFID reader, originally fixed in location with limited signal coverage, is mounted on a drone. The wireless communication between the airborne active RFID reader and a ground-based active RFID tag involves the tag periodically entering sleep mode. Upon waking, it listens for signals from the airborne reader on a pre-defined wireless channel using a pre-defined wake-up method, entering an ultra-low-power operating state for a brief moment. The airborne active RFID reader continuously broadcasts information over a period longer than the tag's sleep-wake cycle, and establishes communication with the tag the instant it listens for signals upon waking, exchanging information. The airborne active RFID reader stores information about the searched target on the ground obtained from communication with the active RFID tag, or transmits it wirelessly to the drone administrator. The method also includes enabling hardware resource sharing between the drone and remote controller, and between the reader and the RFID tag, without affecting their respective communication functions.

[0015] In one implementation, the ground-based active electronic tag is wired to and controlled by one or more IoT terminals.

[0016] The beneficial effects of this invention include:

[0017] 1. Solved the problem of collecting and transmitting hydrological, geological, and disaster monitoring information in remote areas without internet or electricity;

[0018] 2. It solved the problems of personnel search and rescue in areas without internet or electricity, at sea, and during disasters;

[0019] 3. It provides a very important relay communication means for battlefield and emergency disaster relief, especially when the airborne reader is connected to a Beidou short message communication module;

[0020] 4. Since the communication between the airborne electronic tag reader and the electronic tag of the present invention adopts the national unified standard that conforms to CCSA's "Technical Requirements for Communication of Low Duty Cycle Internet of Things Smart Tags", all Internet of Things terminals can communicate with the UAV search system of the present invention through the connection of an electronic tag that conforms to the unified standard.

[0021] 5. It adds a new and important function to drones, greatly expanding the application market for drones; thus bringing huge social and economic benefits. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the structure of a drone search system using active electronic tags according to an embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram illustrating the relationship between the operating parameters of an unmanned aerial vehicle (UAV) reader and the signal coverage range according to an embodiment of the present invention.

[0025] Figure 3 This is a schematic diagram of the working mode of a single-channel UAV-borne reader / writer provided in an embodiment of the present invention;

[0026] Figure 4 This is a schematic diagram illustrating the working mode of a multi-channel UAV-borne reader / writer provided in an embodiment of the present invention. Detailed Implementation

[0027] To enable those skilled in the art to better understand the embodiments of the present invention, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] This invention relies on the soon-to-be-released national key supported standard CCSA, "Low Duty Cycle IoT Smart Tag Communication Technology Requirements," and adopts the ultra-low power wireless long-range sleep-wake technology from the standard. The smart tag reader (also referred to as active electronic tag or electronic tag in this invention document) is installed on a drone, while the electronic tags are carried by field workers and tourists, or installed on animals that need to be tracked and located, as well as on various non-fixed locations of supplies and equipment, including airdropped supplies. Electronic tags connected to sensors are installed on various bridges, roads, or other buildings or electromechanical equipment that are inaccessible to personnel, as well as hydrological and geological disaster monitoring points. For electronic tags connected to mobile IoT terminals that need to be tracked and located, a GPS positioning module is also required. The electronic tags typically operate in a low-power mode, periodically sleeping and then briefly waking up (listening for wake-up signals or actively transmitting signals).

[0029] like Figure 1The diagram shown is a structural schematic of a drone search system using active electronic tags according to an embodiment of the present invention.

[0030] The system comprises a remotely controllable drone, a remote wireless controller for operating the drone, an onboard active electronic tag reader, and at least one active electronic tag carried by the target being searched, or an LDSW mobile phone case capable of wirelessly communicating with the onboard reader (typically connected to a smartphone via wired or wireless means, such as Bluetooth). The drone also includes an onboard communication unit that communicates with the remote controller, and connected to it a GPS satellite positioning unit and an onboard information management unit. The onboard information management unit coordinates communication between the various functional units on the drone. One or more onboard cameras may be included if necessary. Each electronic tag and electronic tag reader has a unique identification number. The electronic tag is connected to one or more IoT terminals; these IoT terminals can be sensors, controllers, GPS satellite positioning modules, or other physical devices. The operation of the IoT terminals is entirely controlled by the connected electronic tags; for example, the GPS module is normally inactive, only starting to operate upon receiving a working command from the connected electronic tag, and ceasing operation after acquiring satellite positioning information. When a drone approaches the target via mobile search and enters the communication range between the onboard electronic tag reader and the electronic tag carried by the target, wireless communication will be established between the reader and the electronic tag, and information will be exchanged. The exchanged information may be the GPS location coordinates of the target, sensor information, short voice information, or other digital information related to the target. The onboard reader stores the information about the target it obtains through the information exchange in the onboard electronic tag reader or transmits it wirelessly to the drone manager.

[0031] Furthermore, when the information transmitted by the target to the airborne reader requires a relatively long collection period, the collection time cannot exceed the time the UAV is within the communication range between the airborne electronic tag reader and the ground electronic tag; otherwise, the information will be the latest information pre-stored in the connected electronic tag. For example, when the reader needs to collect GPS location information from the ground electronic tag, the system needs to consider the time required for the GPS positioning module to cold start and the movement status of the target. Therefore, it is advisable to pre-store the latest location information obtained by the GPS module in the smart electronic tag, or to allow the GPS module to be in a hot-start state.

[0032] Further, the communication method between the electronic tag and the airborne electronic tag reader is such that, except in some special application scenarios where the electronic tag needs to periodically and actively transmit signals, the electronic tag adopts periodic sleep. After waking up, it is in a low-power operating state of listening and detecting signals from the airborne electronic tag reader on a pre-set wireless channel for an instant. The listening and detecting of signals here means that when the electronic tag listens to signals for an instant, it determines whether it receives a radio frequency signal with some or all of the radio frequency characteristics that must be met for wireless communication between the two parties, including communication frequency, modulation method, and coding method, or receives a data signal packet, including a complete data signal packet or an incomplete special data signal packet. If the electronic tag only receives a radio frequency signal meeting the above conditions when listening to signals for an instant, the electronic tag will extend the listening time to receive a complete wireless digital signal packet. After receiving the data signal packet, the electronic tag will parse it according to the requirements of the communication protocol between the two parties. If the electronic tag does not receive a radio frequency signal or a data signal packet meeting the above conditions when listening to signals for an instant, the electronic tag will immediately return to the low-power state at the instant of listening to signals after periodic sleep and waking up.

[0033] As Figure 2 shown, when our application scenario only requires searching and positioning a limited number of ground electronic tags or collecting sensor information, the communication between the airborne electronic tag reader and the electronic tag generally adopts a single-channel communication method, as Figure 3 shown. At this time, the airborne electronic tag reader will adopt a time-division method, that is, within a TD time period greater than the sleep-wake cycle SWC of the electronic tag (SWC < TD), it continuously and uninterruptedly broadcasts information to the electronic tag, catches the instant when the electronic tag wakes up periodically and listens to signals, establishes a communication link with it, and transmits information to it. And within a RT time period after the end of the broadcast (RT > TD), it enters the state of receiving information returned by the electronic tag in a CSMA anti-collision manner. Repeat this process until relevant information transmitted by the searched target is obtained. The length of RT here depends on the time required for the collection and transmission of the relevant information. The entire process where the airborne electronic tag reader broadcasts information within the TD time and then receives information within the RT time can be intermittent. The time interval PT is determined after considering the flight speed U of the unmanned aerial vehicle, the signal coverage length range L in the flight direction of the unmanned aerial vehicle for the communication between the electronic tag reader and the electronic tag, and the magnitudes of the TD and RT values, so as to ensure that the reader can complete the required information interaction with the electronic tags within the search range. Therefore, PT should at least satisfy the relationship PT < L / U - (TD + RT).

[0034] Furthermore, when a single-channel communication method cannot meet the communication needs between the airborne reader and the ground-based electronic tag, a multi-channel communication method should be adopted between the airborne electronic tag reader and the electronic tag, such as... Figure 4 As shown. At this time, the airborne electronic tag reader will arrange a dedicated channel to continuously and repeatedly broadcast information to the electronic tag during a TD time period that is longer than the electronic tag's sleep-wake cycle (SWC). At the same time, it will receive information returned from the electronic tag in CSMA mode on one or more pre-arranged channels, or temporarily arranged in the information broadcast by the electronic tag reader, during the RT time period. Here, the process of the airborne electronic tag reader broadcasting information during the TD time period and receiving information during the RT time period is carried out simultaneously (RT>TD). These two simultaneous processes can be intermittent or continuous, depending on the specific application requirements. When the electronic tag receives the information broadcast by the reader on the arranged dedicated channel, it will immediately jump to one or more of the aforementioned communication channels in CSMA mode, according to the pre-arranged or temporary arrangement in the reader's broadcast information.

[0035] Furthermore, the drone also has at least one onboard camera. Except when necessary to ensure the safe flight of the drone, the camera does not work normally in order to reduce unnecessary power consumption. The system will only activate the camera to perform targeted video recording after the target being searched is located. At this time, the video transmission communication method can be different from the drone flight remote control communication method. That is, the video transmission communication can use a high-speed wireless channel, including but not limited to mobile network communication channels, while the drone flight remote control communication channel can use a low-speed high-frequency or low-frequency communication channel.

[0036] Furthermore, when the information transmitted by the target to the airborne reader needs to be collected by the target over a relatively long period of time, the collection time cannot exceed the time during which the UAV is within the communication range between the airborne electronic tag reader and the ground electronic tag; otherwise, the information will be the latest information pre-stored in the connected electronic tag.

[0037] Furthermore, the information of the searched target can be transmitted to the drone manager in various ways, including but not limited to direct wireless communication between the airborne electronic tag reader and the drone remote controller (in which case both the airborne reader and the drone remote controller use hardware devices capable of wireless communication with each other), or the airborne electronic tag reader first transmits the information to the airborne communication unit via a wired connection, and then transmits it to the drone manager via wireless communication between the airborne communication unit and the drone remote controller, or transmits it to the drone manager via a mobile network communication terminal and a mobile communication network connected to the airborne electronic tag reader via a wired connection; or transmits it to the drone manager via a Beidou short message module and a Beidou satellite communication system connected to the airborne reader.

[0038] Furthermore, the UAV's onboard communication unit and the onboard electronic tag reader can share the same wireless radio frequency transceiver. In this case, the onboard electronic tag reader and the UAV remote controller use the same wireless communication system, except that the two systems use a time-division or time-division plus frequency-division working mode to undertake the communication tasks with the ground electronic tag and with the UAV remote controller.

[0039] This embodiment provides a drone search system using active electronic tags. It leverages LDSW (Low-Power Low-Energy) long-range wireless sleep-wake technology, along with the drone's mobility and high-altitude positioning, to achieve a longer communication distance and a wider search range for the active electronic tags. This transforms a drone originally used only for video recording and simple transportation into a multi-functional drone capable of searching for people and materials, collecting sensor data, inventorying various supplies, and relaying wireless communications. This significantly expands the application scope and market of drones. Particularly in remote areas without internet or electricity, it enables the collection of information from hydrogeological and disaster monitoring sensors, as well as the automatic inspection of the operational status of various facilities and buildings. This invention also links target identification and positioning with video recording, and uses intermittent operation to reduce drone power consumption and increase drone cruising time and range.

[0040] Accordingly, the present invention also provides a drone search method using active electronic tag technology. This method installs an active electronic tag reader / writer, which was originally fixed in position and had a limited signal coverage, on the drone. It takes advantage of the drone's high position, wide field of vision, and longer communication distance, as well as the drone's mobility, so that the same active electronic tag reader / writer can communicate with ground electronic tags over a larger area by changing its position.

[0041] The airborne electronic tag reader stores information about the ground-based target obtained through communication with the ground electronic tag in the airborne electronic tag reader, and transmits it to the drone manager through one or more wireless methods when conditions permit; moreover, the method also achieves hardware resource sharing between the drone remote controller and the drone, and between the reader and the electronic tag, through time division or time division plus frequency division, without affecting the respective communication functions between the drone remote controller and the drone, and between the reader and the electronic tag.

[0042] By connecting a low-duty-cycle active electronic tag carried by the target to one or more IoT terminals via a wired connection, the active electronic tag can control and manage the connected IoT terminals, including but not limited to GPS positioning modules, sensors, controllers, or other physical devices. This ensures that the electronic tag and IoT terminals connected to the target remain in a low-power state for extended periods; they only enter a high-power, long-range communication state when the target is detected by a drone.

[0043] Furthermore, taking the collaboration with DJI drone manufacturers as a model, the reader / writer can be integrated with the drone's existing communication system, or the active electronic tag reader / writer can be a standalone drone-borne accessory that can be installed or removed as needed. This onboard electronic tag reader / writer can also connect to a mobile network terminal, such as a CAT1 module, or a BeiDou short message module, turning the drone into a mobile emergency rescue communication reader / writer gateway. The ground-based electronic tags or LDSW mobile phone clips (where the clips can communicate with each other using low-power digital communication and relay information via the drone's onboard electronic tag reader / writer) employ a periodic sleep mode. Upon waking, they enter a low-power state momentarily while listening for signals from the onboard electronic tag reader / writer on a pre-set wireless channel. This listening / detection signal refers to whether the electronic tag detects signals that conform to the requirements of wireless communication between the two parties at the moment it listens for the signal. The electronic tag must meet some or all of the following radio frequency characteristics: radio frequency signals with communication frequency, modulation method, and encoding method, or receive a data signal packet, including a complete data signal packet or an incomplete special data signal packet. If the electronic tag receives only a radio frequency signal that meets the above conditions at the moment of signal monitoring, the electronic tag will extend the monitoring time to receive a complete wireless digital signal packet. After receiving the data signal packet, the electronic tag will parse it according to the requirements of the communication protocol between the two parties. If the electronic tag does not detect a radio frequency signal that meets the above conditions at the moment of signal monitoring, the electronic tag will immediately return to the low-power state of the moment of signal monitoring after periodic sleep awakening. Through this UAV-borne electronic tag reader gateway and low-cost ultra-low-power ground electronic tags, any IoT terminal connected to the electronic tag can be connected to a remote control center, realizing two-way communication between various IoT terminals and the back-end management background. This solves various problems such as personnel search and rescue, material search, sensor information collection and communication in remote areas.

[0044] The above describes a drone search system and operating method using active electronic tag technology provided by embodiments of the present invention. The various embodiments are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to in the method section. It should be noted that those skilled in the art can make various improvements and modifications to the present invention without departing from its principles, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

[0045] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in connection with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can implement the described functions using different methods for each specific application, but such implementation should not be considered beyond the scope of the invention. The steps of the methods or algorithms described in connection with the embodiments disclosed herein can be implemented directly in hardware, software modules executed by a processor, or a combination of both. Software modules can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disks, removable disks, CD-ROMs, or any other form of storage medium known in the art.

Claims

1. A drone search system using active electronic tag technology, characterized by, The system comprises a remotely controllable drone, a remote wireless controller for controlling the drone, an airborne active electronic tag reader / writer as an independent detachable airborne functional accessory, and at least one active electronic tag carried by the target being searched. The drone includes a GPS satellite positioning unit, an airborne information management unit, and an airborne communication unit that communicates with the remote wireless controller. Each active electronic tag and the active electronic tag reader / writer possesses a unique identification code. The active electronic tag operates in a low duty cycle mode, with periodic sleep and brief periods of operation upon waking, and is connected to one or more IoT terminals. The IoT terminals include, but are not limited to, sensors, controllers, GPS satellite positioning modules, or other physical devices. The active electronic tag also controls the IoT terminals to activate on demand. The drone stops immediately after completing its operation. When the drone approaches the target via mobile search and enters the communication range between the onboard active electronic tag reader and the active electronic tag carried by the target, wireless communication is established between the onboard active electronic tag reader and the electronic tag, and information is exchanged. The exchanged information includes the target's GPS location coordinates, sensor information, short voice information, or other digital information related to the target. The onboard active electronic tag reader stores the information about the target it obtains through this information exchange in the onboard active electronic tag reader or transmits it to the drone manager through a redundant transmission link consisting of a remote wireless remote controller, an onboard communication unit, a mobile communication network, and a Beidou short message module. The communication between the active electronic tag and the airborne active electronic tag reader employs a periodic sleep mode, which includes a low-power operating state for a brief moment after waking up and listening for signals from the airborne active electronic tag reader on a pre-set wireless channel. The listening signal is determined by whether the electronic tag receives an RF signal with some or all of the radio frequency characteristics required for wireless communication between the two parties, including communication frequency, modulation method, and encoding method, or receives a data packet, including a complete data packet or an incomplete special data packet. If the electronic tag receives only a RF signal that meets the conditions at the moment of listening, it will extend the listening time to receive a complete wireless digital signal packet. After receiving the data signal packet, the electronic tag will parse it according to the communication protocol requirements. If the electronic tag does not receive an RF signal or data packet that meets the above conditions at the moment of listening, it will immediately return to the low-power state at the moment of waking up from periodic sleep. When the communication between the airborne active electronic tag reader / writer and the active electronic tag adopts a single-channel communication mode, the airborne active electronic tag reader / writer will adopt a time-division method, that is, within a TD time period greater than the sleep-wake cycle SWC of the electronic tag, continuously and repeatedly broadcast information to the active electronic tag without interruption, and within a RT time period after the end of the broadcast, RT>TD, enter the state of receiving information returned by the active electronic tag in CSMA mode; and so on until the relevant information transmitted from the searched target is obtained; where the length of RT depends on the time required for the transmission of the relevant information; the entire process of the airborne active electronic tag reader / writer broadcasting information within the TD time and receiving information within the RT time can be intermittent, and the time interval PT is determined after considering the flight speed U of the UAV, the communication between the active electronic tag reader / writer and the active electronic tag, the signal coverage length range L in the flight direction of the UAV, and the magnitudes of the TD and RT values, so as to ensure that the reader / writer can complete the required information interaction with the electronic tags within the search range, and PT at least satisfies the relationship PT<L / U-(TD+RT); When the communication between the airborne active electronic tag reader / writer and the active electronic tag adopts a multi-channel communication mode, the airborne active electronic tag reader / writer will arrange a dedicated channel, and within a TD time period greater than the sleep-wake cycle SWC of the electronic tag, while continuously and repeatedly broadcasting information to the active electronic tag without interruption, at the same time, on another or multiple pre-arranged or temporarily arranged channels in the information broadcast by the active electronic tag reader / writer, receive information returned by the active electronic tag in CSMA mode within the RT time period; the process of the airborne active electronic tag reader / writer broadcasting information within the TD time and receiving information within the RT time is carried out simultaneously, RT>TD, and these two simultaneously carried out processes can also be intermittent or continuous without interruption; after receiving the broadcast information of the reader / writer on the dedicated channel, the active electronic tag will immediately jump to another or multiple communication channels according to the pre-arrangement or the arrangement in the information broadcast by the reader / writer and return information to the reader / writer in CSMA mode; It further includes at least one airborne camera; the airborne camera is used for targeted imaging after the searched target is located, and at this time, the communication channel for transmitting the imaging video includes but is not limited to using the flight remote control communication channel of the UAV; the airborne camera is completely powered off under normal conditions, and is only powered on and started after the searched target is located, and adopts an intermittent working mode to reduce the power consumption of the UAV.

2. The drone search system using active electronic tag technology according to claim 1, characterized in that, When the information transmitted from the searched target to the airborne reader / writer requires a long time for the searched target to collect, if the collection time exceeds the time when the UAV is within the communication range of the airborne active electronic tag reader / writer and the ground electronic tag, then the information will be replaced by the latest information pre-stored in the active electronic tag connected thereto.

3. A drone search system using active electronic tag technology according to claim 1, characterized in that, The information of the searched target is transmitted wirelessly to the drone manager, including through direct wireless communication between the airborne active electronic tag reader and the drone remote controller; or the airborne active electronic tag reader first transmits the information to the airborne communication unit via a wired connection, and then transmits it to the drone manager through wireless communication between the airborne communication unit and the drone remote controller; or it is transmitted to the drone manager through a mobile network communication terminal and a mobile communication network connected to the airborne active electronic tag reader via a wired connection; or it is transmitted to the drone manager through a BeiDou short message module and a BeiDou satellite communication system connected to the airborne reader.

4. A drone search system using active electronic tag technology according to claim 1, characterized in that, The UAV onboard communication unit shares the same wireless radio frequency transceiver with the onboard active electronic tag reader. The shared wireless transceiver undertakes two different communication tasks: communication with the electronic tag and communication with the UAV remote controller, using either time division or time division plus frequency division operation mode.

5. A drone search method using active electronic tag technology, characterized in that, An unmanned aerial vehicle (UAV) search system using active electronic tag technology, as described in any one of claims 1-4, comprises: An active RFID reader, originally fixed in location with limited signal coverage, is mounted on a drone. The wireless communication between the airborne active RFID reader and a ground-based active RFID tag involves the tag periodically entering sleep mode. Upon waking, it listens for signals from the airborne active RFID reader via a pre-defined wireless channel, operating in an ultra-low-power state for a brief moment. The airborne active RFID reader continuously broadcasts information over a period longer than the tag's sleep-wake cycle, capturing the moment the tag awakens and listens for signals to establish communication and exchange information. The airborne active RFID reader stores the information about the searched target on the ground obtained from communication with the active RFID tag, or transmits it wirelessly to the drone administrator.

6. A drone search method using active electronic tag technology according to claim 5, characterized in that, The ground-based active electronic tags are searched and connected via wires to one or more IoT terminals for control.

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