An online calibration method for a distributed low-altitude aircraft acoustic detection array

Abstract

This invention discloses an online calibration method for a distributed low-altitude aircraft acoustic detection array, belonging to the field of distributed acoustic detection array calibration technology. The method involves using a UAV carrying an airborne target simulation source. The UAV's ground remote controller controls its flight trajectory to a preset calibration position and then hovers it. The airborne target simulation source controller activates the airborne target simulation source via a wireless communication module, adjusts the gain level of the power amplifier, and sequentially plays standard acoustic signature data of different target characteristics. Simultaneously, the positioning results and target characteristic recognition results of the distributed low-altitude aircraft acoustic detection array to be calibrated are collected and compared with the preset spatial coordinates and labeled standard acoustic signature feature information received by the airborne target simulation source controller. This achieves online calibration of the distributed low-altitude aircraft acoustic detection array, ensuring the performance of the array's positioning and target recognition characteristics is maintained.

Description

Technical Field

[0001] This invention belongs to the field of distributed acoustic detection array calibration technology, specifically relating to an online calibration method for a distributed low-altitude aircraft acoustic detection array. Background Technology

[0002] Low-altitude aircraft generally refer to aircraft flying at an altitude of less than 1,000 meters. Common types include unmanned aerial vehicles (UAVs), helicopters, and manned aircraft such as electric vertical takeoff and landing (eVTOL) aircraft. They are characterized by high maneuverability, vertical takeoff and landing capabilities, low-altitude adaptability, and intelligent control. Combined with electrification and lightweight design, they can flexibly perform tasks such as short-distance transportation and precision operations.

[0003] Low-altitude aircraft have diverse applications in the low-altitude economy: in logistics, drones and eVTOL enable urban aerial delivery and material transport to remote areas; urban transportation explores "flying car" pilot projects to alleviate ground congestion; agricultural plant protection and power line inspection improve operational efficiency through high-precision sensors; and emergency rescue utilizes rapid response advantages to open "air lifelines." In the military field, low-altitude aircraft possess both tactical and strategic value: small drones perform reconnaissance, surveillance, electronic jamming, and swarm strike missions; heavy unmanned cargo platforms ensure frontline material resupply; stealth aircraft infiltrate enemy lines for surprise attacks, while manned-unmanned collaborative systems further expand battlefield information perception and collaborative combat capabilities. With breakthroughs in digital airspace management and energy technology, low-altitude aircraft are accelerating the upgrading of economic sectors and the innovation of military combat modes, becoming a key carrier for future urban development and intelligent national defense.

[0004] With the rapid popularization and technological upgrading of low-altitude aircraft, they are gradually becoming a new type of aerial threat, and their detection and countermeasure technologies have become urgent problems to be solved. Low-altitude aircraft detection technologies include radar, electro-optical imaging, and acoustics. A single technology cannot simultaneously meet the application requirements of complex environments, long distances, all-weather operation, real-time operation, and high-precision identification. Therefore, a multi-technology fusion approach is usually adopted. Acoustic technology can detect the location of targets over a wide area, while optical technology can achieve high-precision positioning and identification at close range.

[0005] Acoustic detection technology, due to its advantages such as flexible array deployment, high low-altitude positioning accuracy, and all-weather real-time monitoring, has become an effective "blind spot" technology for radar and photoelectric imaging detection. Acoustic detection technology uses the directivity of microphone arrays to orient the location of sound source targets. The convergence of multiple array orientations enables the localization and trajectory tracking of dynamic sound source targets. Based on the signal characteristics of the sound source target and the application scenario, the size, power consumption, and weight requirements of the detection equipment can be flexibly configured using scalar or vector microphones and their array configurations. The main limitation of acoustic detection technology is its limited detection range, which is usually compensated for by distributed deployment. Distributed acoustic detection arrays have a large number of microphone elements, hundreds or even thousands of nodes, and often use low-cost microphones. They possess wide-area, all-weather, and real-time monitoring capabilities, requiring long-term stability in the positioning and target recognition performance of the detection array. Therefore, distributed acoustic detection arrays require periodic online calibration to ensure the maintenance of positioning and target recognition performance. Considering its wide-area, all-weather, and real-time monitoring characteristics, the distributed low-altitude vehicle acoustic detection system does not have the conditions to be disassembled and sent to the calibration laboratory. Therefore, it is urgent to propose an online, in-situ calibration method to verify the performance of its positioning accuracy and target characteristic recognition during long-term operation. Summary of the Invention

[0006] The purpose of this invention is to provide an online calibration method for distributed low-altitude vehicle acoustic detection arrays, thereby solving the problem of performance degradation that may occur during long-term operation of existing distributed low-altitude vehicle acoustic detection arrays, which necessitates online calibration.

[0007] The technical solution adopted in this invention is as follows:

[0008] An online calibration method for a distributed acoustic detection array for low-altitude aircraft includes the following steps:

[0009] (1) The airborne target simulation source is suspended on the UAV, and the airborne target simulation source controller and the UAV ground remote controller are placed on the ground;

[0010] (2) The UAV ground remote controller controls the flight trajectory and motion attitude of the UAV carrying the airborne target simulation source, and the airborne target simulation source controller obtains the spatial position coordinates of the airborne target simulation source.

[0011] (3) The UAV carrying the airborne target simulation source hovers at the preset spatial position. The airborne target simulation source controller starts the airborne target simulation source, adjusts the gain level of the power amplifier, and plays the standard acoustic data of different target features in sequence. Simultaneously, it collects the positioning results and target characteristic identification results of the distributed low-altitude aircraft acoustic detection array to be calibrated. It compares the results with the preset spatial position coordinates and the labeled standard acoustic feature information received by the airborne target simulation source controller to realize the online calibration of the distributed low-altitude aircraft acoustic detection array.

[0012] (4) The UAV carrying the airborne target simulation source hovers in sequence at different spatial positions to realize the online calibration of the distributed low-altitude aircraft acoustic detection array with multiple points and multiple target characteristics. The calibration parameters include positioning accuracy and target characteristic recognition accuracy.

[0013] (5) After the calibration procedure is completed, the airborne target simulation source controller shuts down the airborne simulation source, and the UAV ground remote controller controls the UAV to return to home.

[0014] Furthermore, the airborne target simulation source controller is connected to the airborne target simulation source signal via a wireless communication module.

[0015] Furthermore, the airborne target simulation source includes a dynamic loudspeaker, a power amplifier, a power supply, a BeiDou positioning module, and a wireless communication module.

[0016] Furthermore, the airborne target simulation source is suspended below the UAV via a support rod.

[0017] Furthermore, multiple airborne target simulation sources are provided, and each airborne target simulation source is suspended below the UAV by a support rod.

[0018] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0019] 1. In this invention, the UAV carrying the airborne target simulation source hovers along a preset flight trajectory and calibration position. The airborne target simulation source controller located on the ground obtains the spatial position coordinates returned by the Beidou positioning module built into the airborne target simulation source through the wireless communication module. The airborne target simulation source with known spatial position coordinates is used to realize the online calibration of the positioning accuracy of the distributed low-altitude aircraft acoustic detection array.

[0020] 2. In this invention, the airborne target simulation source controller located on the ground remotely controls the airborne target simulation source to play standard acoustic print datasets of different target characteristics through a wireless communication module, simulating different low-altitude aircraft passing through the target area, and realizing online calibration of target characteristic identification of distributed low-altitude aircraft acoustic detection array.

[0021] 3. In this invention, the airborne target simulation source can be directly suspended below the UAV or suspended via a support rod, maintaining a certain distance between the airborne target simulation source and the UAV to prevent the acoustic signature of the hovering UAV from interfering with the recognition of the target simulation acoustic signature by the distributed low-altitude aircraft acoustic detection array. Furthermore, multiple airborne target simulation sources can be simultaneously suspended below the UAV via a certain support rod connection structure, enabling the distributed low-altitude aircraft acoustic detection array to locate and calibrate the acoustic signatures of multiple targets. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort, wherein:

[0023] Figure 1 This is a schematic diagram illustrating the principle of the present invention. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0025] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0026] It should be noted that the labels and letters in the following figures represent similar items, and therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0027] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only used for the purpose of simplifying the description of this invention and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0028] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," not that the structure must be completely horizontal, but can be slightly tilted.

[0029] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0030] Refer to the instruction manual. Figure 1 ,

[0031] An online calibration method for a distributed acoustic detection array for low-altitude aircraft includes the following steps:

[0032] (1) The airborne target simulation source is suspended on the UAV, and the airborne target simulation source controller and the UAV ground remote controller are placed on the ground;

[0033] (2) The UAV ground remote controller controls the flight trajectory and motion attitude of the UAV carrying the airborne target simulation source, and the airborne target simulation source controller obtains the spatial position coordinates of the airborne target simulation source.

[0034] (3) The UAV carrying the airborne target simulation source hovers at the preset spatial position. The airborne target simulation source controller starts the airborne target simulation source, adjusts the gain level of the power amplifier, and plays the standard acoustic data of different target features in sequence. Simultaneously, it collects the positioning results and target characteristic identification results of the distributed low-altitude aircraft acoustic detection array to be calibrated. It compares the results with the preset spatial position coordinates and the labeled standard acoustic feature information received by the airborne target simulation source controller to realize the online calibration of the distributed low-altitude aircraft acoustic detection array.

[0035] (4) The UAV carrying the airborne target simulation source hovers in sequence at different spatial positions to realize the online calibration of the distributed low-altitude aircraft acoustic detection array with multiple points and multiple target characteristics. The calibration parameters include positioning accuracy and target characteristic recognition accuracy.

[0036] (5) After the calibration procedure is completed, the airborne target simulation source controller shuts down the airborne simulation source, and the UAV ground remote controller controls the UAV to return to home.

[0037] Specifically, the airborne target simulation source controller is connected to the airborne target simulation source signal via a wireless communication module.

[0038] Specifically, the airborne target simulation source includes a dynamic loudspeaker, a power amplifier, a power supply, a BeiDou positioning module, and a wireless communication module.

[0039] In this embodiment, the UAV carries an airborne target simulation source, and the UAV's flight trajectory and motion state are controlled by the UAV ground remote controller. The airborne target simulation source integrates a dynamic speaker, power amplifier, power supply, wireless communication module, and BeiDou positioning module. The ground-based airborne target simulation source controller controls the on / off state of the airborne target simulation source, the power amplifier gain level, and the selection of the playback soundprint sequence number, as well as data exchange, via the wireless communication module. The UAV ground remote controller guides the UAV's flight trajectory to a preset calibration position and then hovers it. The airborne target simulation source controller then activates the airborne target simulation source via the wireless communication module, adjusts the power amplifier gain level, and sequentially plays standard soundprint datasets with different target characteristics. This simulates the soundprint characteristics of different low-altitude aircraft passing through the target area. Simultaneously, it collects the positioning results and target characteristic identification results of the distributed low-altitude aircraft acoustic detection array to be calibrated, and compares these results with the preset spatial coordinates and labeled standard soundprint feature information received by the airborne target simulation source controller, thus achieving online calibration of the distributed low-altitude aircraft acoustic detection array.

[0040] Among them, the airborne target simulation source controller obtains the spatial position coordinates returned by the Beidou positioning module built into the airborne target simulation source through the wireless communication module. The target simulation source with known spatial position coordinates is used to realize the online calibration of the positioning accuracy of the distributed low-altitude aircraft acoustic detection array. In addition, the spatial position coordinates of the airborne target simulation source can also be obtained through the UAV ground remote controller.

[0041] Among them, the airborne target simulation source controller remotely controls the airborne target simulation source to play standard acoustic fingerprint datasets with different target characteristics through the wireless communication module, simulates the acoustic fingerprint characteristics of different low-altitude aircraft passing through the target area, and realizes online calibration of target characteristic recognition of distributed low-altitude aircraft acoustic detection array.

[0042] The airborne target simulation source can be directly suspended below the UAV or suspended via a support pole, maintaining a certain distance between the airborne target simulation source and the UAV to prevent the UAV's acoustic signature from interfering with the distributed acoustic detection array's recognition of the target's simulated acoustic signature. Furthermore, multiple airborne target simulation sources can be set up, and these sources can be simultaneously suspended below the UAV via a certain support pole connection structure, enabling the distributed acoustic detection array to locate and calibrate the acoustic signatures of multiple targets.

[0043] Airborne target simulation sources can also be carried by other low-altitude aircraft, balloons, or other aerostats.

[0044] The above description constitutes an embodiment of the present invention. The foregoing descriptions are preferred embodiments of the present invention. Unless there is a clear contradiction or a prerequisite for a particular preferred embodiment, the preferred embodiments can be arbitrarily combined and used. The embodiments and specific parameters described are merely for clearly illustrating the verification process of the invention and are not intended to limit the scope of patent protection of the present invention. The scope of patent protection of the present invention is still determined by its claims. Similarly, any equivalent structural changes made based on the description and drawings of the present invention should also be included within the scope of protection of the present invention.

Claims

1. An online calibration method for a distributed acoustic detection array for low-altitude aircraft, characterized in that, Includes the following steps: (1) The airborne target simulation source is suspended on the UAV, and the airborne target simulation source controller and the UAV ground remote controller are placed on the ground; (2) The UAV ground remote controller controls the flight trajectory and motion attitude of the UAV carrying the airborne target simulation source, and the airborne target simulation source controller obtains the spatial position coordinates of the airborne target simulation source. (3) The UAV carrying the airborne target simulation source hovers at the preset spatial position. The airborne target simulation source controller starts the airborne target simulation source, adjusts the gain level of the power amplifier, and plays the standard acoustic data of different target features in sequence. Simultaneously, it collects the positioning results and target characteristic identification results of the distributed low-altitude aircraft acoustic detection array to be calibrated. It compares the results with the preset spatial position coordinates and the labeled standard acoustic feature information received by the airborne target simulation source controller to realize the online calibration of the distributed low-altitude aircraft acoustic detection array. (4) The UAV carrying the airborne target simulation source hovers in sequence at different spatial positions to realize the online calibration of the distributed low-altitude aircraft acoustic detection array with multiple points and multiple target characteristics. The calibration parameters include positioning accuracy and target characteristic recognition accuracy. (5) After the calibration procedure is completed, the airborne target simulation source controller shuts down the airborne simulation source, and the UAV ground remote controller controls the UAV to return to home; The airborne target simulation source includes a dynamic loudspeaker, a power amplifier, a power supply, a BeiDou positioning module, and a wireless communication module.

2. The online calibration method for a distributed low-altitude vehicle acoustic detection array according to claim 1, characterized in that, The airborne target simulation source controller is connected to the airborne target simulation source signal via a wireless communication module.

3. The online calibration method for a distributed low-altitude vehicle acoustic detection array according to claim 1, characterized in that, The airborne target simulation source is suspended below the UAV by a support rod.

4. The online calibration method for a distributed low-altitude vehicle acoustic detection array according to claim 3, characterized in that, Multiple airborne target simulation sources are provided, and each airborne target simulation source is suspended below the UAV by a support rod.

Images