Millimeter wave radar for detecting foreign objects on airport pavement

Abstract

The invention relates to the field of radar detection, and discloses a millimeter wave radar for detecting foreign objects on an airport pavement, which comprises a shell, a control module fixedly arranged on the inner wall of the bottom of the shell, a power supply module fixedly arranged at the top of the control module, and a transmitting module fixedly arranged at the top of the power supply module. A receiving module is fixedly arranged on the inner wall of the shell, a top plate is fixedly arranged at the top of the shell through screws, an antenna module is fixedly arranged at the top of the top plate, a connecting seat is fixedly arranged at the top of the top plate, an assembling seat is fixedly arranged on the connecting seat through fixing bolts, and a side plate is fixedly arranged on the side face of the shell. The invention has the following advantages and effects: through the advantage of high frequency band and the intelligent signal processing technology, the bottleneck of resolution and stability of the existing system is broken through, and the efficient and stable detection of small FOD is realized.

Description

Technical Field

[0001] This invention relates to the field of radar detection technology, and in particular to a millimeter-wave radar for detecting foreign objects on airport runways. Background Technology

[0002] Foreign objects (FOD, such as metal fragments, rubber blocks, stones, etc.) on airport pavements pose a significant threat to aircraft takeoff and landing safety. The 2000 accident involving the French Concorde aircraft caused by metal strips on the pavement is a typical example. Currently, mainstream FOD detection radars are mainly divided into two categories: fixed (side-light type, tower type) and mobile (vehicle-mounted type). Compared with these, UAV-mounted FOD detection radars have significant advantages such as low cost and no need for personnel to enter the pavement for operation.

[0003] However, existing UAV-borne detection radars have many technical limitations: First, their resolution is insufficient, making it difficult to identify small FODs as small as 15mm, which can easily lead to missed detections; second, their single-polarization design makes them weak at capturing reflected signals from non-metallic FODs such as rubber blocks, resulting in a low detection rate; third, the synthetic aperture (SA) length relies on manual trial and error adjustment, which cannot adaptively match changes in platform stability in strong winds, easily leading to blurred images; and fourth, their clutter suppression capability is lacking, as strong reflective features such as airport pavement seams and textures can easily cause interference and mask FOD signals.

[0004] Crucially, for FOD detection radars mounted on UAVs in the 94GHz band, there are still problems such as rapid signal attenuation in the high-frequency band (affecting detection range and accuracy), high sensitivity to UAV platform motion errors (easily leading to imaging distortion), and difficulty in power consumption control (limiting endurance). Therefore, it is necessary to design a millimeter-wave radar for detecting foreign objects on airport pavements to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide a millimeter-wave radar for detecting foreign objects on airport pavements, in order to solve the above-mentioned problems.

[0006] The above-mentioned technical objective of the present invention is achieved through the following technical solution: a millimeter-wave radar for detecting foreign objects on airport pavement, comprising:

[0007] The housing has a control module fixedly mounted on the bottom inner wall, a power module fixedly mounted on the top of the control module, a transmitter module fixedly mounted on the top of the power module, a receiver module fixedly mounted on the inner wall of the housing, and a top plate fixedly mounted on the top of the housing by screws, with an antenna module fixedly mounted on the top of the top plate.

[0008] A further provision of the present invention is that: a connecting seat is fixedly provided on the top of the top plate, an assembly seat is fixedly provided on the connecting seat by fixing bolts, and a side plate is fixedly provided on the side of the housing.

[0009] A further feature of the present invention is that the transmitting module adopts a 93GHz±1GHz frequency-modulated continuous wave signal source.

[0010] A further feature of the present invention is that the receiving module includes an integrated low-noise amplifier and a 16-bit high-speed analog-to-digital converter.

[0011] A further feature of the present invention is that the antenna module includes one transmitting antenna and two receiving antennas, with the transmitting antenna centered and the receiving antennas symmetrically distributed.

[0012] A further feature of the present invention is that the control module integrates an adaptive motion compensation unit, a dynamic synthetic aperture optimization unit, and an intelligent clutter suppression unit.

[0013] The beneficial effects of this invention are:

[0014] 1. The transmitting module outputs a 93GHz FMCW signal, supporting dynamic bandwidth switching from 1GHz to 2GHz (corresponding to a range resolution of 0.15m-0.075m). The antenna module adopts a single-transmit, dual-receive polarization diversity design with a beamwidth of approximately 20°. The transmitting antenna is centered, and the receiving antennas are symmetrically distributed to ensure that the beam covers the entire detection area in the width direction of the pavement. Simultaneously, it achieves synchronous acquisition of target echoes via horizontal / vertical dual channels. The receiving module integrates a low-noise amplifier and a 16-bit high-speed analog-to-digital converter, enabling high-quality acquisition and digital conversion of radar echo signals. It also integrates a multi-polarization feature real-time calibration module, which acquires horizontal / vertical polarization echoes from fixed strong reflection points on the pavement (such as centerline lights and side lights), calculates channel gain deviation in real time, and dynamically corrects the polarization ratio to eliminate interference from platform vibration on polarization features.

[0015] 2. To address the unstable motion of UAVs in strong winds, a compensation unit integrating GNSS-RTK / IMU and LSTM prediction is designed. This unit can correct attitude errors 20ms ahead of time, ensuring that the phase compensation residual is ≤0.3°. The LSTM model includes an online incremental learning module. After each UAV detection, attitude error data for new wind speed ranges (such as the insufficiently trained 15-30km / h range) is automatically extracted, filtered, and denoised before updating the model parameters. This expands the applicable wind speed range to the full range of 0-40km / h without retraining. The dynamic synthetic aperture optimization unit automatically adjusts the SA length according to the wind speed-distance mapping relationship, avoiding manual trial and error and balancing resolution and signal-to-noise ratio.

[0016] 3. By calculating the polarization ratio (horizontal / vertical echo amplitude) through 2-channel polarization data, the problem of detecting non-metallic targets such as rubber and plastic is solved. The intelligent clutter suppression unit is based on an improved U-Net network and uses an airport clutter feature library to achieve pixel-level clutter removal. The intelligent clutter suppression unit has an adaptive model switching mechanism based on pavement material. By preprocessing the texture features of the echo signal (such as the variance of reflection intensity distribution), it automatically matches the corresponding clutter models of asphalt, concrete, etc., and dynamically adjusts the network segmentation weights to improve the clutter suppression effect in complex mixed pavement scenarios. Attached Figure Description

[0017] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary. The structures, proportions, sizes, etc., drawn in this specification are only used to complement the content disclosed in the specification for those skilled in the art to understand and read, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance, and any modification of the structure, change of the proportional relationship, or adjustment of the size is not permitted.

[0018] Figure 1 This is a schematic diagram of the structure of a millimeter-wave radar for detecting foreign objects on airport pavements, as proposed in this invention.

[0019] Figure 2 This is a cross-sectional structural schematic diagram of a millimeter-wave radar for detecting foreign objects on airport pavements, as proposed in this invention.

[0020] Figure 3 This is an exploded structural diagram of a millimeter-wave radar for detecting foreign objects on airport runways, as proposed in this invention.

[0021] Figure 4 This is a block diagram of a millimeter-wave radar for detecting foreign objects on airport runways, as proposed in this invention.

[0022] Figure 5 This is a schematic diagram of the working status of a UAV-borne millimeter-wave radar.

[0023] In the diagram, 1 is the housing; 2 is the control module; 3 is the power module; 4 is the transmitting module; 5 is the receiving module; 6 is the top plate; 7 is the antenna module; 8 is the connector; 9 is the mounting base; and 10 is the side plate. Detailed Implementation

[0024] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. 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.

[0025] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "circumferential," and "radial," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0026] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more unless otherwise explicitly specified.

[0027] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., 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 connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0028] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0029] See Figures 1-5 This invention provides a millimeter-wave radar for detecting foreign objects on airport pavements, comprising:

[0030] The housing 1 has a control module 2 fixedly installed on the bottom inner wall of the housing 1, a power module 3 fixedly installed on the top of the control module 2, a transmitter module 4 fixedly installed on the top of the power module 3, a receiver module 5 fixedly installed on the inner wall of the housing 1, a top plate 6 fixedly installed on the top of the housing 1 by screws, and an antenna module 7 fixedly installed on the top of the top plate 6.

[0031] Specifically, a connecting seat 8 is fixedly installed on the top of the top plate 6, and an assembly seat 9 is fixedly installed on the connecting seat 8 with fixing bolts. A side plate 10 is fixedly installed on the side of the shell 1.

[0032] Assembly base 9 is used to assemble the drone.

[0033] Specifically, the transmitting module 4 uses a 93GHz±1GHz frequency modulated continuous wave signal source.

[0034] It adopts a 93GHz±1GHz frequency modulated continuous wave (FMCW) signal source, combined with a frequency synthesizer with arbitrarily configurable bandwidth, and supports dynamic switching of bandwidth from 1GHz to 2GHz, corresponding to a distance resolution of 0.15m-0.075m.

[0035] Specifically, receiver module 5 includes an integrated low-noise amplifier and a 16-bit high-speed analog-to-digital converter.

[0036] It includes an integrated low-noise amplifier (noise figure ≤ 4.0dB) and a 16-bit high-speed analog-to-digital converter (ADC sampling rate 25MHz), with channel isolation ≥ 35dB.

[0037] Specifically, antenna module 7 includes one transmitting antenna (horizontally polarized) and two receiving antennas (one horizontally polarized and one vertically polarized), with a beamwidth of 20°. The transmitting antenna is centered, and the receiving antennas are symmetrically distributed.

[0038] Antenna module 7 adopts a single-transmit dual-receive polarization diversity design, including one horizontally polarized transmitting antenna and two receiving antennas (one horizontally polarized receiving antenna and one vertically polarized receiving antenna). The antennas adopt a fixed beam layout with a beamwidth of approximately 20°. By optimizing the spatial layout of the transmitting and receiving antennas (the transmitting antenna is centered and the receiving antennas are symmetrically distributed), it ensures that the beam covers the entire detection area in the width direction of the track surface, while simultaneously achieving synchronous acquisition of target echoes through horizontal / vertical dual-channel polarization. Receiver module 5 includes a multi-polarization feature real-time calibration module, which can dynamically correct polarization channel gain deviations through fixed strong reflection points on the track surface.

[0039] Specifically, the control module 2 integrates an adaptive motion compensation unit, a dynamic synthetic aperture optimization unit, and an intelligent clutter suppression unit.

[0040] The adaptive motion compensation unit integrates GNSS-RTK (positioning accuracy ≤3cm), IMU (sampling rate 2kHz) data from the UAV with an LSTM neural network prediction model to output compensation coefficients for UAV attitude errors (pitch angle, roll angle, yaw angle) in real time, with a compensation response time ≤5ms. The LSTM model supports online incremental learning and can dynamically update parameters based on real-time flight data to expand the applicable wind speed range.

[0041] The LSTM model of the adaptive motion compensation unit is trained with UAV vibration data at wind speeds of 30–40 km / h. It can predict attitude changes within the next 20 ms. Combined with the backpropagation algorithm, the distance term in the SAR imaging formula is compensated in advance, so that the -10 dB width of the imaging point spread function (PSF) is ≤0.07 m. The LSTM model is equipped with a real-time flight data incremental learning module, which can automatically extract error data in new wind speed ranges to update the model parameters.

[0042] The dynamic synthetic aperture optimization unit automatically adjusts the SA length (0.3m-3m) based on real-time wind speed (0-40km / h) and target distance (40-120m) through a preset mapping relationship. When the wind speed is greater than 15km / h, the SA length adaptive reduction algorithm is triggered.

[0043] The intelligent clutter suppression unit has a built-in clutter feature library for airport pavement scenarios (including typical clutter models such as asphalt, concrete, and paint). It uses an improved U-Net network to perform pixel-level clutter segmentation on the echo signal and supports dynamic switching of clutter models that are adaptive to pavement materials. The clutter suppression ratio is ≥25dB.

[0044] The improved U-Net network of the intelligent clutter suppression unit introduces an attention mechanism, assigning weight enhancement coefficients to FOD candidate regions (size 15mm×15mm and above); the clutter feature library supports material recognition based on pavement texture features, and can automatically match corresponding clutter models such as asphalt and concrete. In the actual test at Fuxin UAV airport, the detection rate of rubber tire fragments (20mm×30mm) is ≥95%.

[0045] The principle of using millimeter-wave radar to detect foreign objects on airport pavement is as follows:

[0046] The UAV flies laterally along the outer edge of the pavement (30-60m from the edge line, 30-50m at a height, and 3-11m / s at a speed). The radar initialization parameters are: bandwidth 1GHz, initial SA length 1m, and beam pointing towards the center area of ​​the pavement.

[0047] Transmitting module 4 outputs a 94GHz FMCW signal, receiving module 5 synchronously acquires two channels of polarized echoes, converts them into digital signals via ADC, and multi-polarization feature real-time calibration module corrects polarization channel gain deviation based on fixed strong reflection points on the pavement.

[0048] The adaptive motion compensation unit integrates GNSS-RTK / IMU data with LSTM prediction results (the LSTM model is dynamically updated through incremental learning) to generate real-time compensation coefficients and correct the phase error of the echo signal.

[0049] The dynamic synthetic aperture optimization unit adjusts the SA length based on wind speed sensor data;

[0050] The intelligent clutter suppression unit calls upon a clutter model that matches the pavement material, separates clutter from target signals through an improved U-Net network, and outputs FOD coordinate information by combining fusion imaging and GNSS precise positioning algorithms.

[0051] The foregoing has provided a detailed description of a millimeter-wave radar for detecting foreign objects on airport pavements, as provided by this invention. Specific embodiments have been used to illustrate the principles and implementation methods of this invention. The descriptions of these embodiments are merely illustrative and are intended to aid in understanding the method and core concepts of this invention. It should be noted that those skilled in the art can make various improvements and modifications to this invention without departing from its principles, and these improvements and modifications also fall within the scope of protection of the claims of this invention.

Claims

1. A millimeter-wave radar for detecting foreign objects on airport pavements, characterized in that, include: The housing (1) has a control module (2) fixedly installed on the bottom inner wall of the housing (1), a power module (3) fixedly installed on the top of the control module (2), a transmitter module (4) fixedly installed on the top of the power module (3), a receiver module (5) fixedly installed on the inner wall of the housing (1), a top plate (6) fixedly installed on the top of the housing (1) by screws, and an antenna module (7) fixedly installed on the top of the top plate (6).

2. A millimeter-wave radar for detecting foreign objects on airport pavements according to claim 1, characterized in that, A connecting seat (8) is fixedly installed on the top of the top plate (6), and an assembly seat (9) is fixedly installed on the connecting seat (8) with fixing bolts. A side plate (10) is fixedly installed on the side of the housing (1).

3. A millimeter-wave radar for detecting foreign objects on airport pavements according to claim 1, characterized in that, The transmitting module (4) uses a 93GHz±1GHz frequency modulated continuous wave signal source.

4. A millimeter-wave radar for detecting foreign objects on airport pavements according to claim 1, characterized in that, The receiving module (5) includes an integrated low-noise amplifier and a 16-bit high-speed analog-to-digital converter.

5. A millimeter-wave radar for detecting foreign objects on airport pavements according to claim 1, characterized in that, The antenna module (7) includes one transmitting antenna and two receiving antennas, with the transmitting antenna in the center and the receiving antennas symmetrically distributed.

6. A millimeter-wave radar for detecting foreign objects on airport pavements according to claim 1, characterized in that, The control module (2) integrates an adaptive motion compensation unit, a dynamic synthetic aperture optimization unit, and an intelligent clutter suppression unit.

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