Low-altitude unmanned aerial vehicle global monitoring and directional jamming defense system

Abstract

This invention discloses a low-altitude unmanned aerial vehicle (UAV) all-domain monitoring and targeted jamming defense system. This invention relates to the field of UAV defense technology and includes an airship platform, a detection module, a jamming module, a decoy module, a control module, a power module, and a ground command center. The airship platform is a tethered balloon, and its pod integrates the core working units of the detection module, jamming module, decoy module, control module, and power module. The power module receives AC power from the ground via a tethered cable. This low-altitude UAV all-domain monitoring and targeted jamming defense system overcomes the inherent limitations of traditional ground-deployed defenses, effectively avoids communication blind spots caused by terrain and features, and upgrades from single-area protection to wide-range coverage. It can capture UAV signals at greater distances, allowing sufficient time for countermeasures, accurately distinguishing between compliant UAVs and illegal intrusion targets, avoiding misjudgments and accidental damage, and ensuring the normal operation of legitimate operations.

Description

Technical Field

[0001] This invention relates to the field of unmanned aerial vehicle (UAV) defense technology, specifically a low-altitude UAV all-domain monitoring and targeted jamming defense system. Background Technology

[0002] In recent years, the drone industry has experienced explosive growth. Its high efficiency and low cost have driven the rapid development of civilian applications such as aerial filming, agricultural plant protection, and power line inspection, making it an important tool for empowering social production, life, and construction. However, the inherent characteristics of drones—low speed, slow speed, and small size—make them a new and difficult-to-defend threat, exhibiting a significant double-edged sword effect. As the technological threshold decreases, cases of drone abuse and malicious use continue to surge, highlighting increasingly prominent security risks.

[0003] Authorized publication number CN119942848A describes a precise control system and method for low-altitude airspace unmanned aerial vehicles (UAVs). This system, through the coordination of a UAV control platform, navigation decoy equipment, and navigation protection equipment, can intelligently distinguish between cooperative and non-cooperative UAVs. While implementing navigation decoy control on non-cooperative UAVs, it avoids misinterpreting cooperative UAVs, solving the problems of traditional control methods failing to distinguish friend from foe and wasting airspace resources, thus possessing certain advantages in precise control. However, this existing technology still has limitations in ground deployment or conventional deployment modes: its signal propagation is easily blocked by obstacles such as buildings, mountains, and forests, creating communication blind spots and protection dead zones; ground environment has high signal loss and many noise sources, resulting in a low signal-to-noise ratio, making it difficult to capture long-distance UAV signals early, and limiting the warning distance; the system's continuous capability relies on manual operation and equipment charging rotation, resulting in high labor costs and the inability to achieve 24 / 7 uninterrupted monitoring; overall, it remains at the defensive level, unable to cover the vast protection areas required for large, high-value targets such as airports, and does not address the needs of sensitive areas for concealment and passive detection, showing a significant gap from the core defense requirements of absolute early warning and automated denial.

[0004] Current mainstream drone countermeasure technologies generally suffer from similar limitations: either they cannot effectively distinguish between friend and foe, leading to friendly fire, or they are limited by the deployment platform, making it difficult to achieve wide-area, blind-spot-free, and long-duration protection. This invention aims to solve the practical problems of existing drone defense systems, such as limited coverage, untimely early warning, blind spots, high operating costs, and easy exposure of their own electromagnetic signals. Summary of the Invention

[0005] The purpose of this invention is to provide a low-altitude unmanned aerial vehicle (UAV) all-domain monitoring and targeted jamming defense system to solve the problems mentioned in the background art.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a low-altitude unmanned aerial vehicle (UAV) all-domain monitoring and directional jamming defense system, including an airship platform, a detection module, a jamming module, a decoy module, a control module, a power supply module, and a ground command center; The airship platform is a tethered balloon, and its pod integrates the core working units of the detection module, interference module, decoy module, control module and power module; The power module receives AC power transmitted from the ground via a tethered cable and converts it into stable DC power to power other modules. The control module establishes a data connection with the ground command center via a tethered cable to transmit detection signals and receive control commands. The detection module is used to capture the radio signals of the UAV and analyze the relevant information; the jamming module is used to emit directional electromagnetic interference signals to cut off the communication link of the UAV; and the decoy module is used to emit false satellite navigation signals to guide the flight trajectory of the UAV.

[0007] The high-altitude and low-altitude nodes of the airship platform work together. The wide-area detection unit of the high-altitude node can capture UAV signals in the entire airspace, while the jamming module of the low-altitude node can achieve targeted and precise countermeasures based on the guidance information of the high-altitude node, forming an integrated system of all-area monitoring and targeted jamming defense.

[0008] Preferably, in the implementation of the low-altitude UAV all-domain monitoring and targeted jamming defense system, the layered airship networking platform layer serves as the core support base, adopting a networking deployment of high-altitude wide-area early warning nodes and low-altitude precision countermeasure nodes. The high-altitude wide-area early warning nodes utilize long-endurance tethered balloons with a payload of 15 kg, hovering at an altitude of 3-5 km, and are equipped with wide-area detection modules and passive positioning modules. The low-altitude precision countermeasure nodes utilize mobile tethered balloons with a payload of 8 kg, hovering at an altitude of 500-1000 m, and are equipped with precision countermeasure modules and close-range verification detection. The unit consists of two types of nodes connected to ground equipment via tethered cables. The cables integrate power transmission lines and data transmission lines. The power transmission lines transmit 220V AC power from the ground to the power module inside the pod, which converts it to 28V DC power to provide stable power to all equipment inside the pod. The data transmission lines enable real-time signal transmission between the pod equipment and the ground command center. At the same time, data synchronization between the two types of nodes is ensured through three links: fiber optic, 4G / 5G, and BeiDou short message. After the high-altitude node detects a target, it can immediately guide the low-altitude node to adjust its attitude and preheat the countermeasure equipment. The multimodal perception layer operates synchronously. The radio spectrum detection module captures the remote control, image transmission, and telemetry signals of the drone in the 70MHz-6GHz frequency band. The infrared thermal imaging detection module collects the thermal profile features of the drone. The acoustic feature detection module captures the specific frequency acoustic signals generated by the drone's propeller rotation. The RID identity verification module scans and listens to the identity signal packets continuously broadcast by the drone in the Wi-Fi or Bluetooth frequency band, and analyzes the information contained therein, such as the drone serial number, location, altitude, speed, control station location, and timestamp. The initial screening of the target is completed by cross-comparison of the three detection signals, and the blacklist and whitelist are combined to distinguish between compliant drones and unauthorized drones. The intelligent decision-making layer receives all signals and identity verification results transmitted by the multimodal perception layer, conducts threat assessment through signal feature comparison and target flight trajectory analysis, generates appropriate countermeasure commands, and sends them to the collaborative countermeasure layer. The coordinated countermeasures layer responds to the command and starts working. The directional jamming module concentrates the co-channel jamming energy into a narrow beam through a highly directional antenna, accurately cutting off the image transmission and remote control links of the target UAV. The multi-frequency navigation deception module generates pseudo satellite navigation signals covering eight frequency points: GPS-L1, GPS-L5, BDS-B1, BDS-B2, GLO-G1, GLO-L5, GAL-E1, and GAL-E5a. The power of this pseudo signal is higher than that of the real satellite signal. It can suppress the real signal received by the UAV and inject a preset virtual flight trajectory message to guide the UAV to the designated area. The overall control layer coordinates collaboration across all levels, while the ground command center receives real-time air situation information, equipment operating status, and countermeasure results from each node through three links. This enables unified scheduling and control of UAV defense across the entire domain, ensuring efficient connection of the entire process from target detection, identification, assessment to countermeasures, and forming a complete closed loop for low-altitude UAV defense.

[0009] Preferably, the aerostat platform includes a high-altitude node and a low-altitude node, with the high-altitude node having a higher altitude than the low-altitude node. The two nodes achieve data synchronization through multi-link redundant transmission. The high-altitude node is equipped with a wide-area detection unit for capturing UAV signals over long distances and sending guidance information to the low-altitude node. The low-altitude node is equipped with a precision countermeasure unit that adjusts its attitude and initiates interference or deception operations based on the guidance information.

[0010] Preferably, the detection module includes a radio spectrum detection unit, an infrared thermal imaging unit, and an acoustic feature detection unit; the radio spectrum detection unit operates in the frequency range of 70MHz-6GHz and is used to capture UAV remote control, image transmission, and telemetry signals; the infrared thermal imaging unit is used to collect target thermal profile features; the acoustic feature detection unit is used to capture UAV propeller acoustic signals; the detection results of the three units are transmitted to the control module for cross-verification.

[0011] Preferably, the detection module also integrates a RID identity verification unit, which is used to scan and parse the identity signal packet broadcast by the drone. The identity signal packet contains the drone serial number, location, speed, and control station location information. The control module has a built-in blacklist and whitelist storage unit, which compares the parsed drone serial number with the blacklist and whitelist to distinguish between compliant drones and illegally intruding drones.

[0012] Preferably, the decoy module supports eight navigation frequencies: GPS-L1, GPS-L5, BDS-B1, BDS-B2, GLO-G1, GLO-L5, GAL-E1, and GAL-E5a. The decoy module generates a fake signal with the same format as the real satellite navigation signal. Through the deployment of multiple airship nodes in a network, it achieves regional coverage suppression of GPS signals. The power of this fake signal is higher than that of the real satellite signal, covering and suppressing the real navigation signals received by UAVs in the target area, and injecting preset virtual flight trajectory information into the UAVs. The decoy modules of multiple airship nodes work together to achieve full-domain interference, forming a surface-kill navigation suppression of the protected area, ensuring that all illegal UAVs in the area are deprived of navigation control.

[0013] Preferably, the jamming module is equipped with a highly directional antenna to concentrate the jamming energy within a narrow beam; the jamming module adjusts the antenna direction according to the location of the UAV determined by the detection module, and transmits a co-frequency jamming signal only to the target UAV, cutting off the image transmission and remote control link between the target UAV and the remote controller.

[0014] Preferably, the control module is configured with a passive detection priority working mode. Under normal circumstances, only the passive working unit of the detection module is activated and no electromagnetic signals are emitted. When the detection module confirms that the target is an illegal intrusion and reaches the preset threat level, the control module activates the interference module or the decoy module. After the operation is completed, it immediately switches back to the passive detection mode.

[0015] Preferably, the power module includes a grid power supply unit and a solar auxiliary power supply unit; the grid power supply unit receives 220V AC power from the ground through a tethered cable and converts it into 28V DC power; the solar auxiliary power supply unit and the grid power supply unit form a redundant power supply to ensure continuous operation of the system.

[0016] Preferably, the control module integrates an intelligent decision-making unit, which classifies threat levels based on the UAV's identity information, flight trajectory, flight speed, and payload signals. For different threat levels, the intelligent decision-making unit automatically matches interference, deception, or coordinated countermeasure strategies and sends execution instructions to the interference module or deception module.

[0017] Preferably, it also includes a cloud-based management and control platform, which establishes communication connections with multiple airship platforms and a ground command center; the cloud-based management and control platform stores a UAV characteristic database, blacklists and whitelists, and a countermeasure strategy database, dynamically updates the data, and synchronizes it to the control modules of each airship platform; the cloud-based management and control platform receives the working status and countermeasure results of each airship platform, realizing multi-area collaborative defense scheduling.

[0018] This system achieves a deep integration of comprehensive monitoring and precise defense through a collaborative network of high-altitude wide-area monitoring and low-altitude targeted countermeasures. The wide-area detection capabilities of the high-altitude nodes ensure early warning over a large airspace, allowing sufficient time for countermeasure operations; while the targeted jamming technology of the low-altitude nodes enables precise strikes against illegal targets. The combination of the two achieves both broad-area protective coverage and avoids the electromagnetic pollution and collateral damage problems associated with traditional all-area jamming.

[0019] This invention provides a low-altitude unmanned aerial vehicle (UAV) all-domain monitoring and targeted jamming defense system. It has the following beneficial effects: This low-altitude UAV all-domain monitoring and targeted jamming defense system overcomes the inherent limitations of traditional ground-based defense through the deep integration of a layered airship networking platform and multimodal sensing technology. The high-altitude loitering characteristics of the airships ensure unobstructed radio signal propagation paths, effectively avoiding communication blind spots caused by terrain and features. Combined with a collaborative networking design of high-altitude wide-area early warning and low-altitude precision countermeasures, it upgrades from single-area protection to broad-range coverage, enabling the capture of UAV signals at greater distances and allowing sufficient time for countermeasure operations. The combination of multimodal detection units and RID identity verification technology accurately distinguishes compliant UAVs from illegal intrusion targets through cross-verification of signal characteristics, thermal profiles, and acoustic features, as well as identity information comparison, avoiding misjudgments and accidental damage, and ensuring the normal operation of legitimate activities.

[0020] This low-altitude UAV all-domain monitoring and targeted jamming defense system utilizes a redundant power supply architecture combining the power grid and solar energy, along with stable power transmission via tethered cables, to achieve uninterrupted 24 / 7 monitoring without relying on manual rotation or equipment charging, significantly reducing operating costs. The control module's passive detection-priority mode normally does not actively emit electromagnetic signals, only initiating active countermeasures when high-threat targets are confirmed, minimizing its own electromagnetic exposure and meeting the concealment protection needs of sensitive areas. The intelligent decision-making and collaborative countermeasure mechanism dynamically matches jamming, decoy, or combined strategies based on the target threat level. Combined with cross-regional collaborative scheduling on a cloud-based management platform, it forms a complete closed loop of detection-identification-decision-response, improving the efficiency and reliability of handling various illegal UAVs and providing comprehensive, high-security low-altitude defense for critical facilities.

[0021] The GPS signal area suppression technology of this system achieves a full-domain jamming effect through multi-node networking. It not only solves the problem of limited coverage of traditional single-point deception, but also ensures the effectiveness and reliability of suppression by using a design where the format of the fake signal is consistent with that of the real signal. At the same time, combined with directional jamming technology, it achieves a dual countermeasure of full-domain navigation suppression and directional communication cutoff, which greatly improves the efficiency of dealing with illegal drones. Attached Figure Description

[0022] Figure 1 This is a flowchart illustrating the workflow of the low-altitude unmanned aerial vehicle (UAV) all-domain monitoring and targeted jamming defense system of the present invention. Figure 2 This is a state transition diagram of the low-altitude unmanned aerial vehicle (UAV) global monitoring and directional jamming defense system of the present invention. Detailed Implementation

[0023] 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.

[0024] Please see Figure 1 and Figure 2 The present invention provides a technical solution: a low-altitude unmanned aerial vehicle (UAV) all-domain monitoring and directional jamming defense system, including an airship platform, a detection module, a jamming module, a decoy module, a control module, a power supply module, and a ground command center; The airship platform is a tethered balloon, and its pod integrates core working units such as a detection module, a jamming module, a decoy module, a control module, and a power module. The power module receives AC power transmitted from the ground via a tethered cable and converts it into stable DC power to power other modules. The control module establishes a data connection with the ground command center via a tethered cable to transmit detection signals and receive control commands. The detection module is used to capture the drone's radio signals and analyze related information; the jamming module is used to emit directional electromagnetic interference signals to cut off the drone's communication link; and the decoy module is used to emit false satellite navigation signals to guide the drone's flight trajectory.

[0025] The aerostat platform includes a high-altitude node and a low-altitude node. The high-altitude node is stationed at a higher altitude than the low-altitude node, and the two achieve data synchronization through multi-link redundant transmission. The high-altitude node is equipped with a wide-area detection unit to capture UAV signals from a distance and send guidance information to the low-altitude node. The low-altitude node is equipped with a precision countermeasure unit to adjust its attitude and initiate jamming or decoy operations based on the guidance information.

[0026] It should be further explained that the high-altitude wide-area early warning node uses a long-endurance tethered balloon with a payload of 15 kg. The tethered cable is fixed by ground anchoring equipment. After takeoff, the hovering altitude is maintained at 3-5 km. The pod of this node integrates a wide-area detection unit and a passive positioning unit. The wide-area detection unit operates at a frequency covering 70MHz-6GHz and can capture remote control, image transmission, and telemetry signals from long-distance UAVs. The passive positioning unit determines the initial position information of the UAV by calculating the signal arrival time difference and azimuth angle. When implementing the signal arrival time difference and azimuth angle calculation method, the detection units of the high-altitude node and the low-altitude node simultaneously receive the UAV signal, record the signal reception time difference of the two units, combine the known position coordinates of the two nodes, and determine the azimuth angle of the UAV relative to the node through geometric relationships. Then, the position information is further corrected by combining the signal strength, and finally the accurate positioning of the UAV is obtained. The low-altitude precision countermeasure node uses a motorized tethered balloon with a payload of 8 kg, maintaining an altitude of 500-1000 m. The pod carries a precision countermeasure unit, a close-range verification and detection unit, and an attitude adjustment module. The precision countermeasure unit includes directional jamming components and navigation deception components. The close-range verification and detection unit is used to perform secondary signal acquisition and feature confirmation of the targets identified by the high-altitude node. The attitude adjustment module integrates a barometric pressure sensor, a three-axis gyroscope, and an actuator, which can correct platform offset in real time.

[0027] The two types of nodes form a multi-link redundant transmission network via fiber optics, 4G / 5G, and BeiDou short message service. The high-altitude node transmits the captured UAV signal characteristics, preliminary positioning information, and flight trajectory data to the low-altitude node through redundant links, and simultaneously to the ground command center. After receiving the data, the attitude adjustment module of the low-altitude node adjusts the hovering attitude of the tethered balloon according to the target positioning information, so that the antenna of the precision countermeasure unit is aligned with the target direction. The close-range verification and detection unit is activated and collects the target's close-range signal, compares it with the signal characteristics transmitted by the high-altitude node, and confirms that there is no error. After confirmation, the precision countermeasure unit enters standby mode. If the target enters the preset countermeasure range, the low-altitude node can directly respond to the instructions of the ground command center or, according to the guidance signal of the high-altitude node, initiate directional jamming or navigation deception operations to achieve precise interception of the target. The network deployment of the two types of nodes can cover a larger area and avoid the signal blockage problem of a single platform. Through the synergy of high-altitude early warning and low-altitude countermeasure, the early detection and rapid response capability of distant targets is improved.

[0028] The detection module includes a radio spectrum detection unit, an infrared thermal imaging unit, and an acoustic feature detection unit. The radio spectrum detection unit operates in the frequency range of 70MHz-6GHz and is used to capture UAV remote control, image transmission, and telemetry signals. The infrared thermal imaging unit is used to collect target thermal profile features. The acoustic feature detection unit is used to capture the acoustic signals of the UAV propellers. The detection results of the three units are transmitted to the control module for cross-verification.

[0029] It should be further explained that the radio spectrum detection unit continuously scans the airspace within a preset frequency range of 70MHz-6GHz, capturing remote control signals, image transmission signals, and telemetry signals transmitted between the UAV and the remote controller. It extracts characteristic parameters such as signal frequency, modulation method, and code rate through its built-in signal processing circuit. Simultaneously, it combines signal arrival time and azimuth data to preliminarily calculate the UAV's position information. The infrared thermal imaging unit is equipped with a high-definition infrared camera, which collects thermal radiation signals from targets in the airspace through an optical lens. After converting these signals into electrical signals, it performs image enhancement and noise reduction processing to generate a clear thermal image. Then, an image segmentation algorithm is used to extract the target's thermal contour features, distinguishing the UAV from the background environment and other flying objects. The acoustic feature detection unit has a built-in high-sensitivity microphone that directionally collects acoustic signals in the 200-2000Hz frequency band. After filtering out irrelevant noise in the environment, it performs a Fourier transform on the collected signals to analyze the frequency distribution and amplitude changes, extracting specific acoustic features generated by the UAV's propeller rotation.

[0030] The detection data from the three units is transmitted to the control module in real time. The control module first compares the signal features extracted by the radio spectrum detection unit with the built-in UAV signal feature library, and then combines the thermal profile features of the infrared thermal imaging unit to determine whether the target has the shape and thermal radiation characteristics of a UAV. At the same time, it uses the frequency features of the acoustic feature detection unit to exclude non-UAV targets such as birds and balloons. Through the mutual verification and supplementation of the three types of features, the accurate identification and positioning of UAV targets is completed, ensuring accurate target capture in complex airspace environments and avoiding misjudgments that may occur with a single detection method.

[0031] The working principle of the infrared thermal imaging unit includes: the network structure of the UAV thermal contour recognition network includes an input layer, convolutional layer, pooling layer, fully connected layer, and output layer. The input layer receives a 256×256 pixel thermal image acquired by the infrared thermal imaging unit. The convolutional layer extracts local features such as edges and textures from the image using 3×3 convolutional kernels. The pooling layer uses max pooling to compress the feature map dimension while retaining key information. The fully connected layer integrates and classifies the extracted features. The output layer outputs the determination result of whether the target is a UAV and key parameters of the thermal contour. During network training, an infrared thermal imaging dataset containing various types of UAVs, birds, balloons, and other targets is used. The network parameters are adjusted using a gradient descent algorithm to enable the network to accurately distinguish UAVs from other interfering targets. The feature extraction logic focuses on extracting key features such as the aspect ratio, thermal radiation intensity distribution, and contour edge smoothness of the thermal contour. Targets with an aspect ratio in the range of 1.5-3.5, thermal radiation intensity distributed with a high center and low edges, and smooth contour edges without obvious protrusions have a significantly higher probability of being identified as UAVs.

[0032] It should be further explained that the consistency judgment criteria for multimodal cross-verification are specifically set as follows: the radio signal feature matching degree must reach more than 80% of the features of the corresponding UAV model in the preset feature library, and the feature matching items include core parameters such as frequency, modulation method, and code rate; in the thermal profile features, the error between the extracted target aspect ratio and the preset UAV aspect ratio does not exceed 15%, and the thermal radiation intensity distribution conforms to the UAV's thermal radiation characteristics; in the acoustic features, the deviation between the extracted propeller rotation frequency and the preset UAV acoustic frequency does not exceed 5Hz. When at least two of the judgment results of the three modes meet the above threshold requirements, it is judged as consistent, and the target is confirmed to be a UAV; if only one mode meets the threshold requirements, a second verification is initiated, the signal is re-acquired and verified again, until a clear judgment result is obtained.

[0033] The detection module also integrates a RID identity verification unit, which is used to scan and parse the identity signal packets broadcast by the drone. The identity signal packets contain the drone serial number, location, speed, and control station location information. The control module has a built-in blacklist and whitelist storage unit, which compares the parsed drone serial number with the blacklist and whitelist to distinguish between compliant drones and illegally intruding drones.

[0034] It should be further explained that the RID identity verification unit operates on a frequency band that covers specific Wi-Fi and Bluetooth bands. It continuously scans the airspace through its built-in signal receiving circuit to capture the identity signal packets broadcast by the drone during flight in real time. These signal packets are transmitted in a fixed format and contain information such as the drone's unique serial number, real-time location coordinates, flight altitude, flight speed, control station ground location, and signal transmission timestamp.

[0035] After the signal is captured, the RID identity verification unit starts the demodulation and decoding process. First, the received radio frequency signal is filtered and amplified to remove environmental interference signals. Then, the original data in the signal packet is parsed through the corresponding communication protocol, converted into digital information that the control module can recognize, and transmitted in real time.

[0036] The control module has a built-in independent blacklist and whitelist storage unit, which supports manual entry, batch import and dynamic update of serial numbers of compliant drones through ground command center or cloud management platform. These compliant drones include authorized operation equipment such as power inspection, film and television aerial photography, and emergency rescue. Their serial numbers are permanently or temporarily stored in the whitelist. At the same time, the serial numbers of drones that have been confirmed to have been illegally accessed or have security risks are stored in the blacklist.

[0037] After receiving the drone serial number transmitted by the RID identity verification unit, the control module immediately compares it with the blacklist and whitelist. If the serial number matches the whitelist, it is determined to be a compliant drone, and no alarm or countermeasures are triggered; only its flight trajectory and operational information are recorded. If the serial number matches the blacklist, it is directly determined to be an illegal target, and an activation command is immediately sent to the jamming module or decoy module. If the serial number does not match any list, the results of radio spectrum detection, infrared thermal imaging, and acoustic feature detection are further cross-verified to confirm whether there is identity spoofing or unauthorized flight. This avoids misjudgment caused by relying solely on identity verification, ensures accurate differentiation between compliant drones and illegally intruding drones, and provides a reliable basis for subsequent targeted countermeasures.

[0038] The decoy module supports eight navigation frequencies: GPS-L1, GPS-L5, BDS-B1, BDS-B2, GLO-G1, GLO-L5, GAL-E1, and GAL-E5a. It generates a fake signal with the same format as the real satellite navigation signal. Through a network of multiple aerostat nodes, it achieves regional coverage suppression of GPS signals. This fake signal has a higher power than the real satellite signal, covering and suppressing the real navigation signals received by UAVs within the target area, and injecting preset virtual flight trajectory information into the UAVs. The coordinated operation of multiple aerostat nodes' decoy modules can achieve full-domain interference, forming a surface-kill navigation suppression effect on the protected area, ensuring that all illegal UAVs within the area are deprived of navigation control.

[0039] The GPS signal suppression of this system is achieved through the network coverage of multiple airship nodes. The decoy module of a single low-altitude node can cover an airspace with a radius of 1-3km. After multiple nodes are deployed in a network at a preset interval, their false signal coverage ranges overlap to form a global GPS signal suppression area. That is, the network form of global interference achieves an area kill effect, forcing all illegal UAVs in the area to receive false navigation signals, unable to obtain real location information, and thus being guided to a safe area.

[0040] It should be further explained that the decoy module has built-in signal generation units for eight navigation frequencies, corresponding to GPS-L1, GPS-L5, BDS-B1, BDS-B2, GLO-G1, GLO-L5, GAL-E1, and GAL-E5a, respectively, fully covering the core operating frequency bands of the world's mainstream satellite navigation systems. Depending on the type of navigation system the UAV is compatible with, the corresponding frequency can be activated individually or multiple frequencies can be started simultaneously to work together.

[0041] The signal generation unit uses a dedicated chip to simulate the modulation method, encoding rules, and transmission format of real satellite navigation signals, ensuring that the generated pseudo signal is structurally identical to the real signal and meets the recognition requirements of the UAV navigation receiver module. At the same time, it is equipped with a power amplifier circuit to adjust the power of the pseudo signal to be higher than the strength of the real satellite signal that the UAV can receive at its current position. It is then transmitted directionally through a high-gain antenna to cover and suppress the real signal, causing the UAV to prioritize receiving the pseudo signal and abandon tracking the real signal, thereby seizing control of the navigation source.

[0042] The virtual flight trajectory message is generated by the control module according to a preset defense strategy. The message contains key parameters such as latitude, longitude, altitude, speed, and heading. The dedicated algorithm for the virtual flight trajectory message is implemented as follows: First, the current real-time position coordinates of the UAV, the boundary coordinates of the defense area, and the coordinates of the safe landing point are obtained to delineate the sensitive area that is prohibited from entering. Second, based on the UAV's flight speed, turning radius, and other mechanical characteristics, a smooth and continuous virtual path is planned that does not cross the sensitive area. The interval between path nodes is set according to the flight speed to ensure that the UAV can follow stably. Finally, the latitude, longitude, altitude, speed, and heading parameters of the path nodes are encapsulated into a message in the format of satellite navigation signals and injected into the pseudo-navigation signal. The parameter calculation is based on the current real-time position of the UAV, the boundary of the defense area, and the coordinates of the safe landing point. A dedicated algorithm is used to plan a virtual trajectory that conforms to the UAV's flight mechanical characteristics to avoid the UAV refusing to receive signals due to abnormal trajectory parameters.

[0043] For different defense scenarios, the message can be set with different deception modes: In the no-fly zone scenario, the injected virtual location information is always outside the no-fly zone, causing the drone to determine that its current position does not meet the takeoff conditions or that it needs to leave the no-fly zone immediately; in the directed drive-away scenario, continuously increasing target position parameters are injected to guide the drone to fly away from the core protection area; in the special handling scenario, cyclically changing heading parameters are injected to cause the drone to enter a circular motion state and be unable to continue to approach the target area.

[0044] The decoy module communicates with the control module in real time, receiving start commands, frequency selection signals, and trajectory parameters from the control module. It dynamically adjusts the transmission frequency, power, and message content of the fake signal to ensure the decoy effect is maintained throughout the drone's flight until the drone completes a preset forced landing, return, or drive-away maneuver. The specific decoy frequency switching conditions are as follows: when the detection module detects a change in the drone's navigation signal frequency band, the decoy module automatically switches to the corresponding decoy frequency within 0.5 seconds, maintaining consistency between the fake signal and the drone's receiving frequency band; when the control module detects through trajectory analysis that the drone is not flying along the virtual trajectory and has deviated from the path by more than 100 meters for more than 10 seconds, it automatically initiates a frequency combination switch, activating a preset backup frequency combination to regain control of the drone's navigation; furthermore, when the cloud-based management platform issues a frequency switching command, the decoy module responds synchronously to ensure consistency with the overall defense strategy.

[0045] The jamming module is equipped with a highly directional antenna, which concentrates the jamming energy into a narrow beam. The jamming module adjusts the antenna direction according to the location of the UAV determined by the detection module, and only transmits the same frequency jamming signal to the target UAV, cutting off the image transmission and remote control link between the target UAV and the remote controller.

[0046] It should be further explained that the core component of the jamming module is a highly directional antenna. This antenna adopts a parabolic reflector structure design. By optimizing the curvature of the reflector and the position of the feed source, the jamming energy is focused within a narrow beam range. The beam coverage is controlled within a specific angle range, ensuring that the energy is concentrated on the target area.

[0047] The jamming module establishes real-time data interaction with the detection and control modules. After the detection module captures the remote control and image transmission signals of the UAV, it analyzes the key parameters such as the operating frequency band and modulation method of the signal, and transmits the real-time position coordinates of the UAV to the control module. The control module calculates the target azimuth and pitch angles based on the position information, sends an antenna pointing adjustment command to the jamming module, and drives the stepper motor on the antenna to adjust its attitude so that the beam axis is accurately aligned with the target UAV.

[0048] The interference signal generation unit receives the frequency band matching command issued by the control module, generates an interference signal with the same frequency as the UAV's communication link, and transmits it to the highly directional antenna after being processed by the power amplifier circuit. The signal is focused by the antenna and transmitted directionally, directly acting on the UAV's receiving antenna, cutting off the remote control signal and image transmission signal link between the UAV and the remote controller, forcing the UAV to execute the preset return, hovering or landing procedure.

[0049] During signal transmission, the power monitoring unit built into the jamming module detects the transmission power in real time and dynamically adjusts the output power according to the target distance to ensure that no excess electromagnetic radiation is generated within the effective jamming range. The jamming power adjustment range in the countermeasure strategy is dynamically set according to the target distance: when the UAV is within 1 kilometer of the countermeasure node, the jamming power is set to 300-500 watts; when the distance is 1-3 kilometers, the power is set to 200-300 watts; and when the distance is more than 3 kilometers, the power is set to 100-200 watts, ensuring that excess electromagnetic radiation is avoided while effectively jamming the target. At the same time, the high directional characteristics of the antenna prevent the jamming energy from spreading to the surrounding airspace, preventing the impact on communication base stations, power equipment, civilian electronic equipment and other surrounding facilities, thus achieving precise jamming of the target UAV and electromagnetic protection of the surrounding environment.

[0050] The control module is configured to operate in a passive detection priority mode. Under normal circumstances, only the passive working unit of the detection module is activated, and no electromagnetic signals are emitted. When the detection module confirms that the target is an illegal intrusion and reaches the preset threat level, the control module will activate the interference module or the decoy module. After the operation is completed, it will immediately switch back to the passive detection mode.

[0051] It should be further explained that after the control module is powered on, it automatically switches to the passive detection priority working mode. In this mode, only the passive working units of the detection module are activated, including the passive listening component for radio spectrum detection, the infrared thermal imaging unit, the acoustic feature detection unit, and the signal acquisition component for RID identity verification. All of the above units only receive and analyze natural signals and UAV broadcast signals in the airspace, and do not actively emit any electromagnetic signals to avoid revealing their own position.

[0052] The passive working units operate continuously and collaboratively. The radio spectrum detection component passively listens to the remote control, image transmission and telemetry signals of the UAV in the 70MHz-6GHz frequency band. The infrared thermal imaging unit collects the thermal radiation characteristics of airspace targets in real time. The acoustic feature detection unit captures acoustic signals in specific frequency bands. The RID identity verification component scans and receives the UAV's identity broadcast packets. All collected data is transmitted to the control module in real time for integration and analysis.

[0053] The control module has built-in threat determination logic. It sets preset conditions by combining whether the drone's identity information matches the blacklist or whitelist, whether the flight trajectory is close to the boundary of the sensitive area, and whether the flight status has abnormal acceleration, circling, or other behaviors. When an unauthorized drone meets the combined conditions of entering the protection warning circle, matching the signal characteristics of an illegal target, and the flight trajectory pointing to the core area, it is determined that the preset threat level has been reached.

[0054] At this point, the control module sends a start command to the jamming module or decoy module. The command contains key parameters such as the target's location, signal frequency band, and threat type. After receiving the command, the jamming module or decoy module initiates directional jamming or navigation decoy operations according to a preset strategy.

[0055] Once the countermeasures are completed—that is, the drone returns, makes an emergency landing, or moves away from the protected area—the control module, after confirming that the target has escaped the threat state through the signal fed back by the detection module, immediately sends a shutdown command to the jamming module or decoy module to cut off the power supply to its active transmission unit. At the same time, it controls itself and the detection module to return to the initial mode in which only the passive unit works. Throughout the process, the transmission duration and range of the active signal are strictly controlled to meet the needs of sensitive areas for covert protection.

[0056] The power module includes a grid power supply unit and a solar auxiliary power supply unit; the grid power supply unit receives 220V AC power from the ground through a tethered cable and converts it into 28V DC power; the solar auxiliary power supply unit and the grid power supply unit form a redundant power supply to ensure the continuous operation of the system.

[0057] It should be further explained that the power supply unit of the power module is connected to the ground 220V AC power through a power transmission line integrated inside the mooring cable. This power transmission line uses a wear-resistant and tensile-resistant special cable and is arranged in isolation from the data transmission line to avoid electromagnetic interference. The power transmission line transmits the AC power to the power conversion module in the pod. This module has built-in rectifier circuit, filter circuit and voltage regulator circuit. First, the rectifier circuit converts the AC power to DC power, then the filter circuit removes noise signals from the current, and finally the voltage regulator circuit accurately stabilizes the voltage at 28V, providing continuous and stable power support for all power-consuming units such as the detection module, interference module, decoy module and control module.

[0058] The solar panels of the solar-assisted power supply unit adopt a flexible design and are attached to the surface of the airbag of the airship without changing the aerodynamic shape and flight stability of the airship. After the solar panels convert the light energy into direct current, it is transmitted to the charging management module. This module is responsible for controlling the charging current and voltage to avoid overcharging damage to the energy storage unit. The energy storage unit is a dedicated lithium battery pack used to store the electrical energy converted from solar energy, forming a redundant power supply architecture with the grid power supply unit.

[0059] The power module has a built-in voltage monitoring unit that monitors the grid voltage status in real time. When the grid power supply is normal, it prioritizes grid power supply while the solar auxiliary power supply unit charges the energy storage unit. When the grid power supply is interrupted or the voltage is abnormal, the voltage monitoring unit immediately sends a switching signal, and the charging management module quickly switches the power supply mode to solar power supply or energy storage unit power supply to ensure that each power module is not affected by the power supply interruption. When the grid power supply is restored to normal, it automatically switches back to grid power supply mode, and the energy storage unit continues to receive solar charging. Through the coordinated work and seamless switching of the two power supply methods, the system can work continuously in various environments without relying on battery replacement or manual charging.

[0060] The control module integrates an intelligent decision-making unit, which classifies the threat level based on the UAV's identity information, flight trajectory, flight speed, and payload signals. For different threat levels, the intelligent decision-making unit automatically matches interference, deception, or coordinated countermeasure strategies and sends execution commands to the interference module or deception module.

[0061] It should be further explained that the intelligent decision-making unit of the control module receives multi-source input information in real time through the data interface. The identity information comes from the UAV serial number and blacklist / whitelist comparison results parsed by the RID identity verification unit. The flight trajectory data comes from the real-time position coordinates and historical path records of the UAV calculated by the detection module. The flight speed data is obtained by parsing telemetry signals. The payload signal is extracted by analyzing specific frequency band signal features through the radio spectrum detection unit. The above information is integrated synchronously to form complete target situation data.

[0062] The intelligent decision-making unit has built-in grading rules, classifying threat levels based on a combination of identity legitimacy, trajectory threat level, speed threshold, and payload characteristics. Specifically, the combined judgment logic for threat level classification is as follows: Identity legitimacy is based on whether the serial number matches a blacklist or whitelist; if it matches the whitelist, it is directly classified as Level 1. Trajectory threat level is based on the straight-line distance between the drone and the boundary of the sensitive area: a distance greater than 5 kilometers indicates no threat, 1-5 kilometers indicates an approaching threat, and less than 1 kilometer indicates a direct threat. The speed threshold is set as the upper limit of normal operating speed; exceeding this limit increases the threat level. Payload signal characteristics are based on whether a specific frequency band of payload communication signal is detected; if detected, it is determined to be carrying a suspicious payload. Serial numbers matching the whitelist and whose flight trajectories are far from sensitive areas are classified as Level 1; serial numbers not matching any list but whose flight trajectories do not indicate a clear threat are classified as Level 2; serial numbers not authorized and whose flight trajectories approach the boundaries of sensitive areas are classified as Level 3; serial numbers matching the blacklist or whose flight speed exceeds the normal operating range are classified as Level 4; and serial numbers carrying suspicious payload signals and whose trajectories point directly to the core protection area are classified as Level 5.

[0063] For different threat levels, the intelligent decision-making unit presets corresponding countermeasure strategy libraries. The first level only records flight information without initiating countermeasures; the second level initiates continuous RID tracking and signal feature verification; the third level sends instructions to the decoy module to activate the corresponding navigation frequency and inject virtual trajectory messages far away from sensitive areas; the fourth level simultaneously activates the jamming module and the decoy module, with the jamming module cutting off the UAV's remote control and image transmission links and the decoy module guiding it to make an emergency landing in a safe area; the fifth level initiates full-link countermeasures, with the jamming module using maximum power for directional suppression, the decoy module injecting cyclic trajectory messages, and simultaneously sending early warning signals to the ground command center.

[0064] During the countermeasure process, the intelligent decision-making unit continuously receives target status data from the detection module. If it detects that the target has left the countermeasure range or its status has changed, it adjusts the parameters of the countermeasure strategy in real time, such as switching the decoy frequency and adjusting the interference power, to ensure that the countermeasure operation is dynamically adapted to the target status and to achieve targeted handling.

[0065] It also includes a cloud-based management and control platform, which establishes communication connections with multiple airship platforms and the ground command center; the cloud-based management and control platform stores a database of UAV characteristics, blacklists and whitelists, and a countermeasure strategy database, dynamically updates the data and synchronizes it to the control modules of each airship platform; the cloud-based management and control platform receives the working status and countermeasure results of each airship platform, and realizes multi-regional collaborative defense scheduling.

[0066] It should be further explained that the cloud-based management platform establishes stable connections with multiple airship platforms and ground command centers through 4G, 5G, and fiber optic communication networks, forming a communication architecture with full coverage. The cloud-based management platform has three core databases built-in. The drone characteristic database stores the radio signal characteristics, infrared thermal profile parameters, acoustic frequency characteristics, and identity signal packet formats of different drone models, covering key information on civilian, industrial, and common illegal drones. The blacklist and whitelist database supports three update methods: manual entry, batch import, and remote synchronization. It can record information such as the serial number, operating area, and operating time of compliant drones, while also recording the identification and handling records of illegally intruding drones. The countermeasure strategy database corresponds to different threat levels and stores preset schemes such as directional interference parameters, navigation deception frequency combinations, and virtual trajectory planning rules.

[0067] The cloud-based control platform receives real-time air situation data uploaded by each airship platform, including UAV location, signal characteristics, identity information, equipment operating status such as operating parameters of each module, power supply status, antenna attitude, and countermeasure results such as target handling methods and final status. At the same time, it collects dispatch instructions and area protection requirements from the ground command center.

[0068] The platform categorizes and organizes the received data, automatically updates the three core databases, adds new UAV features to the feature database, adjusts the blacklist and whitelist based on the latest authorization information, optimizes the strategy database parameters based on the countermeasure effect, and synchronizes the updated data to all associated airship platform control modules and the ground command center through the communication network to ensure the consistency of strategies at each node.

[0069] When an airship platform detects an illegal drone flying at a distance or across regions, the cloud-based control platform quickly analyzes the target's flight trajectory, sends early warning signals and target characteristic data to other airship platforms along the trajectory, and instructs relevant nodes to activate their detection modules and adjust their attitudes to stand by. At the same time, it coordinates with the ground command center to prepare for emergencies, forming a cross-regional defense closed loop of detection-early warning-coordinated interception, realizing unified scheduling and efficient linkage of drone defense in multiple regions, and covering a wider protection range.

[0070] This invention overcomes the inherent limitations of traditional ground-based defense deployments by deeply integrating a layered aerostat networking platform with multimodal sensing technology. The high-altitude loitering characteristics of the aerostats ensure unobstructed radio signal propagation paths, effectively avoiding communication blind spots caused by terrain and features. Combined with a collaborative networking design integrating high-altitude wide-area early warning and low-altitude precision countermeasures, it upgrades from single-area protection to broad-area coverage, enabling the capture of drone signals at greater distances and allowing sufficient time for countermeasure operations. The combination of multimodal detection units and RID identity verification technology, through cross-verification of signal characteristics, thermal profiles, and acoustic features, and comparison of identity information, accurately distinguishes compliant drones from illegal intrusion targets, avoiding misjudgments and accidental damage, and ensuring the normal operation of legitimate activities.

[0071] This invention possesses highly efficient and continuous defense capabilities and excellent environmental adaptability. Through a redundant power supply architecture combining the power grid and solar energy, coupled with stable power transmission via tethered cables, it achieves 24 / 7 uninterrupted monitoring without relying on manual rotation or equipment charging, significantly reducing operating costs. The control module's passive detection priority mode does not actively emit electromagnetic signals under normal circumstances, only initiating active countermeasures when high-threat targets are confirmed, reducing its own electromagnetic exposure and meeting the concealed protection needs of sensitive areas. The intelligent decision-making and collaborative countermeasure mechanism dynamically matches interference, decoy, or combined strategies based on the target threat level. Combined with cross-regional collaborative scheduling on a cloud-based management platform, it forms a complete closed loop of detection-identification-decision-response, improving the efficiency and reliability of handling various illegal drones and providing comprehensive, highly secure low-altitude defense for critical facilities.

[0072] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0073] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A low-altitude unmanned aerial vehicle (UAV) all-domain monitoring and targeted jamming defense system, characterized in that, It includes an airship platform, detection module, jamming module, decoy module, control module, power module, and ground command center; The airship platform is a tethered balloon, and its pod integrates the core working units of the detection module, interference module, decoy module, control module and power module; The power module receives AC power transmitted from the ground via a tethered cable and converts it into stable DC power to power other modules. The control module establishes a data connection with the ground command center via a tethered cable to transmit detection signals and receive control commands. The detection module is used to capture the radio signals of the UAV and analyze the relevant information; the jamming module is used to emit directional electromagnetic interference signals to cut off the communication link of the UAV; and the decoy module is used to emit false satellite navigation signals to guide the flight trajectory of the UAV.

2. The low-altitude unmanned aerial vehicle (UAV) all-domain monitoring and targeted jamming defense system according to claim 1, characterized in that: The airship platform includes a high-altitude node and a low-altitude node. The high-altitude node is stationed at a higher altitude than the low-altitude node, and the two achieve data synchronization through multi-link redundant transmission. The high-altitude node is equipped with a wide-area detection unit, which is used to capture UAV signals at a long distance and send guidance information to the low-altitude node. The low-altitude node is equipped with a precision countermeasure unit, which adjusts its attitude and initiates interference or deception operations based on guidance information.

3. The low-altitude unmanned aerial vehicle (UAV) all-domain monitoring and targeted jamming defense system according to claim 2, characterized in that: The detection module includes a radio spectrum detection unit, an infrared thermal imaging unit, and an acoustic feature detection unit. The radio spectrum detection unit operates in the frequency range of 70MHz-6GHz and is used to capture UAV remote control, image transmission, and telemetry signals. The infrared thermal imaging unit is used to collect target thermal profile features. The acoustic feature detection unit is used to capture UAV propeller acoustic signals. The detection results of the three units are transmitted to the control module for cross-verification.

4. The low-altitude unmanned aerial vehicle (UAV) all-domain monitoring and targeted jamming defense system according to claim 3, characterized in that: The detection module also integrates an RID identity verification unit, which is used to scan and parse the identity signal packet broadcast by the UAV. The identity signal packet contains the UAV serial number, location, speed and control station location information. The control module has a built-in blacklist / whitelist storage unit that compares the parsed drone serial number with the blacklist / whitelist to distinguish between compliant drones and illegally intruding drones.

5. The low-altitude unmanned aerial vehicle (UAV) all-domain monitoring and targeted jamming defense system according to claim 4, characterized in that: The decoy module supports eight navigation frequencies: GPS-L1, GPS-L5, BDS-B1, BDS-B2, GLO-G1, GLO-L5, GAL-E1, and GAL-E5a. It generates a fake signal with the same format as the real satellite navigation signal, and through a network of multiple aerostat nodes, achieves regional coverage suppression of the GPS signal. This fake signal has a higher power than the real satellite signal, covering and suppressing the real navigation signal received by UAVs within the target area, and injecting preset virtual flight trajectory information into the UAVs. The coordinated operation of the decoy modules of multiple aerostat nodes can achieve full-domain interference, forming a surface-kill navigation suppression effect on the protected area, ensuring that all illegal UAVs within the area are deprived of navigation control.

6. The low-altitude unmanned aerial vehicle (UAV) all-domain monitoring and targeted jamming defense system according to claim 5, characterized in that: The jamming module is equipped with a highly directional antenna, which concentrates the jamming energy into a narrow beam. The jamming module adjusts the antenna direction according to the location of the UAV determined by the detection module, and transmits the same-frequency jamming signal only to the target UAV, cutting off the image transmission and remote control link between the target UAV and the remote controller.

7. The low-altitude unmanned aerial vehicle (UAV) all-domain monitoring and targeted jamming defense system according to claim 6, characterized in that: The control module is configured with a passive detection priority working mode. Under normal circumstances, only the passive working unit of the detection module is activated and no electromagnetic signals are emitted. When the detection module confirms that the target is an illegal intrusion and reaches the preset threat level, the control module will activate the interference module or the decoy module. After the operation is completed, it will immediately switch back to the passive detection mode.

8. The low-altitude unmanned aerial vehicle (UAV) all-domain monitoring and targeted jamming defense system according to claim 7, characterized in that: The power module includes a grid power supply unit and a solar auxiliary power supply unit; the grid power supply unit receives AC power from the ground through a tethered cable and converts it into DC power; the solar auxiliary power supply unit and the grid power supply unit form a redundant power supply to ensure continuous operation of the system.

9. The low-altitude unmanned aerial vehicle (UAV) all-domain monitoring and targeted jamming defense system according to claim 8, characterized in that: The control module integrates an intelligent decision-making unit, which classifies threat levels based on the UAV's identity information, flight trajectory, flight speed, and payload signals. For different threat levels, the intelligent decision-making unit automatically matches interference, deception, or coordinated countermeasure strategies and sends execution instructions to the interference module or deception module.

10. The low-altitude unmanned aerial vehicle (UAV) all-domain monitoring and targeted jamming defense system according to claim 1, characterized in that: It also includes a cloud-based management and control platform, which establishes communication connections with multiple airship platforms and a ground command center; the cloud-based management and control platform stores a database of UAV characteristics, blacklists and whitelists, and a countermeasure strategy database, dynamically updates the data and synchronizes it to the control modules of each airship platform; the cloud-based management and control platform receives the working status and countermeasure results of each airship platform, realizing multi-area collaborative defense scheduling.

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