CN115586517A

CN115586517A - Array radar foreign matter detection system and method

Info

Publication number: CN115586517A
Application number: CN202211145242.0A
Authority: CN
Inventors: 韩松; 牛晓丽; 王岩飞
Original assignee: Aerospace Information Research Institute of CAS
Current assignee: Aerospace Information Research Institute of CAS
Priority date: 2022-09-20
Filing date: 2022-09-20
Publication date: 2023-01-10

Abstract

The present disclosure provides an array radar foreign object detection system and method, the system includes: the radar transmitting units form a transmitting array at a plurality of preset transmitting positions and are used for transmitting radar detection signals to a detection area on an airport runway; the radar receiving units form a receiving array at a plurality of preset receiving positions and are used for receiving radar echo signals scattered by a detection area; the radar imaging unit is used for performing imaging processing on the basis of the received echo signals of the multiple positions and generating a radar image in a detection area; the radar image detection unit is used for detecting whether foreign matters exist in the radar image of the detection area; and the position forming mechanism is used for bearing and fixing the radar transmitting unit at a preset transmitting position and is also used for bearing and fixing the radar receiving unit at a preset receiving position. The clutter suppression ability can be strengthened to this application, improves FOD detectability.

Description

Array radar foreign matter detection system and method

Technical Field

The disclosure relates to the technical field of radars, in particular to a system and a method for detecting foreign matters by using an array radar.

Background

FOD (FOD) generally refers to some Foreign material, debris or Object that may damage an aircraft or system, often referred to as a runway Foreign Object. FOD presents a serious hazard, and many cases prove that foreign objects on airfield runways can be easily sucked into engines to cause engine failure, and fragments can be accumulated in mechanical systems to influence the normal operation of equipment such as undercarriages, wings and the like, so that the damage to the aircrafts and the precious life loss are caused, and huge economic losses are also caused.

In the early stage, most of the airport runway supervision work in China is mainly manually completed by road patrolling personnel, and the runway is closed during road patrolling, so that the flight traffic capacity is low in efficiency and poor in reliability, and precious runway service time is occupied.

Currently, FOD detection can be through methods of optical video detection and radar detection. Optical video detection is performed by performing optical image recognition on the acquired runway image, and recognition of foreign objects is affected by the resolution of the optical image. Moreover, the optical video detection is greatly influenced by the weather environment, and the detection efficiency and the reliability of the optical video detection are greatly reduced when the optical video detection is in severe weather such as rain, fog and the like or works at night. Consequently, increased and adopted the millimeter wave radar to carry out FOD and surveyed, the millimeter wave radar can realize surveying night, has relative beam narrow, signal bandwidth broad, volume weight advantage such as little, is used for FOD radar check out test set extensively.

However, the existing millimeter wave radar for FOD detection is still greatly influenced by weather, compared with microwave, the millimeter wave is more obviously influenced by weather, and the detection performance is greatly reduced or even the millimeter wave radar cannot work when atmospheric moisture is increased and in foggy days and rainy days. In addition, the millimeter wave radar for FOD detection adopts background cancellation to suppress ground clutter, but the ground clutter changes with weather and seasons, and directly influences the detection performance. In addition, the angular resolution of the FOD detection millimeter wave radar is fixed, the difference between the far-distance radar irradiation area and the near-distance radar irradiation area of the ground to be detected is large, and the foreign matter detection system of the array radar with inconsistent far-end and near-end detection performances is caused.

Disclosure of Invention

The present disclosure provides an array radar foreign object detection system and method. The first aspect of the present disclosure provides an array radar foreign matter detection system including a radar and a position forming mechanism, the radar including: the radar transmitting units are respectively arranged at the preset positions of all the transmitting units to form a transmitting array and used for transmitting radar detection signals to the detection area; the radar receiving units are respectively arranged at the preset positions of the receiving units to form a receiving array and used for receiving echo signals obtained by scattering and/or reflecting the detection signals by targets or clutter; the radar imaging unit is used for carrying out imaging processing on the basis of the received echo signals of the multiple positions and generating a radar image of the detection area; the radar image detection unit is used for detecting whether foreign matters exist in the radar image of the detection area or not; the position forming mechanism is used for bearing the radar transmitting unit and fixing the radar transmitting unit at a preset transmitting position on one side of the airport runway; the position forming mechanism enables the radar transmitting unit to transmit radar signals at a fixed preset transmitting position; the position forming mechanism is also used for bearing the radar receiving unit and fixing the radar receiving unit at a preset receiving position on one side of the airport runway; the position forming mechanism enables the radar receiving unit to receive radar echo signals at a fixed preset receiving position. Optionally, the radar transmitting unit and the radar receiving unit structurally belong to the same structural body or belong to different structural bodies.

Optionally, the radar transmitting unit includes a radar transmitter and a radar transmitting antenna, and the radar receiving unit includes a radar receiving antenna, a radar receiver, a radar data collecting unit, and a radar data recording unit.

Optionally, the position forming mechanism comprises a plurality of structural units, and each structural unit comprises a connecting and rotating mechanism, a motion attitude measuring unit and a supporting structure.

Optionally, one way of the preset position of the radar transmitting unit and the preset position of the radar receiving unit is as follows: on the same side of the detection zone; and the distance between any two radar transmitting units is smaller than or equal to the imaging resolution, or/and the distance between any two radar receiving units is smaller than or equal to the imaging resolution.

Optionally, another way of presetting the positions of the radar transmitting unit and the radar receiving unit is as follows: distributed on opposite sides of the detection zone; and the distance between any two radar transmitting units is smaller than or equal to the imaging resolution, or/and the distance between any two radar transmitting units is smaller than or equal to the imaging resolution.

Optionally, another way for the radar receiving unit to preset a position is: when the distance between any two radar transmitting units is smaller than or equal to the imaging resolution, the distance between two adjacent radar receiving units is larger than the distance between two adjacent radar transmitting units, and the distance between two adjacent radar receiving units is smaller than or equal to the short-range end width of a detection area corresponding to the wave beam of the radar receiving unit.

Optionally, the number of the radar transmitting units satisfies that the number of the radar transmitting units multiplied by the distance between two adjacent radar transmitting units is larger than the width of the long-distance end of the detection area corresponding to the beams of two adjacent radar receiving units.

Optionally, another way for the radar transmitting unit to preset the position is: when the distance between any two radar receiving units is smaller than or equal to the imaging resolution ratio, the distance between every two adjacent radar transmitting units is larger than the distance between every two adjacent radar receiving units, and the distance between every two adjacent radar transmitting units is smaller than or equal to the short-range end width of an irradiated detection area corresponding to beams transmitted by the two adjacent radar transmitting units.

Optionally, the number of the radar receiving units satisfies that the number of the radar receiving units multiplied by the distance between two adjacent radar receiving units is larger than the width of a long-distance end of an irradiation detection area corresponding to beams emitted by two adjacent radar emitting units.

A second aspect of the present disclosure provides an array radar foreign object detection method, the method including: the radar transmitting unit and the radar receiving unit are arranged along the preset positions on one side or two sides of the airport runway; the radar transmitting unit transmits radar detection signals to a detection area on an airport runway at a plurality of preset transmitting positions; the radar receiving unit receives echo signals scattered by the radar detection signals acting on the detection area at a plurality of preset receiving positions; the radar imaging unit carries out imaging processing by using echo signals corresponding to the receiving and transmitting combinations of different preset transmitting positions and preset receiving positions to obtain a radar image of a detection area; the radar image detection unit detects foreign matters by utilizing radar images and detects whether foreign matters exist in a detection area.

Optionally, the transmitting the radar detection signal to the detection area on the airport runway is to adjust a radar transmission beam direction of a radar transmission antenna of the radar transmission unit by using the connection and rotation mechanism of the motion position forming mechanism, so that the radar transmission beam irradiates the detection area on the airport runway.

Optionally, when the preset launching position is located on either side of the airport runway, the preset launching position is a fixed position in which a support structure of the position forming mechanism is located; the predetermined receiving position is a fixed position in which a support structure of the position forming mechanism is located when the predetermined receiving position is located on either side of the airport runway.

Optionally, the fixed positions are connected with lines between adjacent fixed positions on either side of the airport runway, and the lines are combined into straight lines or broken lines.

The technical scheme provided by the embodiment of the disclosure can have the following beneficial effects:

the embodiment of the disclosure discloses an array radar foreign matter detection system and method, which can acquire a radar image in a detection area, detect foreign matters according to the radar image in the detection area and determine whether foreign matters exist in the detection area. Carry out the foreign matter through obtaining the radar image and detect, for the mode that adopts millimeter wave radar detection and/or optics video to combine among the prior art, can effectively reduce radar resolution unit area, and then reduce background clutter intensity by a wide margin, improve the signal-to-clutter ratio, the reinforcing suppresses the clutter ability, improves the FOD detection capability. In addition, because the area of the resolution unit is reduced by adopting an imaging method instead of reducing the area of the resolution unit by narrow beams, the millimeter wave band which is easy to realize the narrow beams does not need to be adopted, and the microwave band with low atmospheric attenuation and rain attenuation can be adopted, so that the influence of weather conditions on the detection capability is reduced.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

Drawings

FIG. 1 is a schematic diagram of an array radar foreign object detection system in accordance with an exemplary embodiment;

FIG. 2 is a schematic diagram illustrating the structure and placement of an array radar foreign object detection system according to an exemplary embodiment;

FIG. 3 is a schematic diagram illustrating the structure and placement of an array radar foreign object detection system according to an exemplary embodiment;

FIG. 4 is a schematic diagram illustrating the structure and placement of an array radar foreign object detection system according to an exemplary embodiment;

FIG. 5 is a schematic diagram illustrating the structure and placement of an array radar foreign object detection system according to an exemplary embodiment;

FIG. 6 is a schematic diagram of an exemplary embodiment of a foreign object detection system with radar array;

FIG. 7 is a schematic diagram of the structure and placement of an array radar foreign object detection system according to an exemplary embodiment;

FIG. 8 is a schematic flow diagram illustrating a method for detecting foreign objects by an array radar in accordance with an exemplary embodiment;

FIG. 9 is a schematic flow diagram illustrating a method for detecting foreign objects by an array radar in accordance with an exemplary embodiment;

FIG. 10 is a schematic diagram of a prior art array radar foreign object detection system;

FIG. 11 is a schematic diagram of an array radar foreign object detection system in accordance with an exemplary embodiment;

FIG. 12 is a schematic diagram of an array radar foreign object detection system in accordance with an exemplary embodiment;

fig. 13 is a schematic structural diagram of an array radar foreign object detection system according to an exemplary embodiment.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. The technical solutions in the embodiments of the present application are clearly and completely described, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application. In the present application, the embodiments and features of the embodiments may be arbitrarily combined with each other without conflict.

First, related art to which embodiments of the present application relate will be briefly described.

Radars are electronic devices that detect objects using electromagnetic waves. The radar emits electromagnetic waves to irradiate a target and receives the echo of the target, so that information such as the distance from the target to an electromagnetic wave emission point, the distance change rate (radial speed), the azimuth and the altitude is obtained.

Synthetic Aperture Radar (SAR) uses a small antenna to move along the track of a long linear array at a constant speed and radiate coherent signals, and performs coherent processing on echoes received at different positions, thereby obtaining an imaging Radar with higher resolution.

The radar beam width refers to an included angle between two half-power points of a beam.

The angular resolution of a radar refers to the ability of the radar to resolve two targets in the angular direction, and is generally determined by the beam width, with the narrower the beam, the better the angular resolution. The beam width of the radar is proportional to the wavelength of the radar and inversely proportional to the length of the antenna.

FIG. 10 is a schematic diagram of the operation of a millimeter wave radar FOD detection. As shown in fig. 10, a plurality of millimeter wave radars are arranged side by side on one side or both sides of the runway along the length direction of the runway, and when the radars detect, each radar transmits a detection signal to irradiate the runway area, and covers the runway area which is irradiated by the radar through a rotating beam, and covers all the runway areas through the plurality of radars.

The angular resolution of this radar detection mode depends on the radar beam width, which is the wider the angular resolution is. The radar beam width is related to the wavelength and the antenna size, when the size of the radar antenna is limited, the shorter the wavelength is, the narrower the radar beam is, the better the angular resolution is, and the lower the corresponding clutter intensity is, which is a determining factor for detecting the adopted millimeter wave frequency band by the FOD radar at present.

Adopt the millimeter wave radar to survey FOD, can realize surveying night, have relative beam narrowly, signal bandwidth broad, volume weight advantage such as little, be used for different kinds of FOD radar check out test set extensively.

However, compared with microwaves, the millimeter wave radar for FOD detection is more significantly affected by weather, and the detection performance is greatly reduced or even disabled in the case of increased atmospheric moisture and in the case of fog and rain. In addition, the millimeter wave radar for FOD detection adopts background cancellation to suppress ground clutter, but the ground clutter changes with weather and seasons, and directly influences the detection performance. In addition, the angular resolution of the FOD detection millimeter wave radar is fixed, the difference between the far distance radar irradiation area and the near distance radar irradiation area of the ground to be detected is large, and the performance of far-end detection is reduced.

An object of the disclosed embodiment is to provide an array radar foreign object detection method and system, which can overcome the defects of FOD detection by existing optical video and millimeter wave radars, and meet the requirements of FOD detection in all weather and high performance all day.

The array foreign matter detection method and system provided by the embodiment of the invention have at least the following beneficial effects:

(1) Enhancing the ability of inhibiting background clutter

The method is superior to high-resolution imaging, the area of a radar resolution unit can be effectively reduced, the intensity of background clutter is greatly reduced, the signal-to-clutter ratio is improved, the clutter suppression capability is enhanced, and the FOD detection capability is improved.

(2) Improving all-weather detection capability

The FOD detection is carried out by adopting high-resolution imaging, so that the relevance between the FOD detection resolution and the wave band can be reduced, the FOD detection can be carried out by adopting a microwave wave band, the penetrating capability of the microwave wave band to water vapor, fog and rain is obviously superior to that of a millimeter wave band, and the all-weather detection capability can be effectively improved.

The method and the system for detecting the array foreign matters have the advantages of enhancing the capability of inhibiting background clutter, improving the FOD detection performance, improving the all-weather detection capability and the like.

The disclosed embodiment provides an array radar foreign matter detection system, which is shown in fig. 1 and includes:

the radar transmitting units 101-10 m are respectively arranged at the preset positions of each transmitting unit to form a transmitting array and used for transmitting radar detection signals to a detection area;

the radar receiving units 201 to 20n are respectively arranged at preset positions of each receiving unit to form a receiving array and are used for receiving echo signals obtained by scattering and/or reflecting the detection signals by targets or clutter;

a radar imaging unit 300, configured to perform imaging processing based on the received echo signals of the multiple positions, and generate a radar image of the detection area;

a radar image detection unit 400 for detecting whether a foreign object exists in a radar image of the detection area;

the position forming mechanism 500 is used for bearing the radar transmitting unit and fixing the radar transmitting unit at a preset transmitting position on one side of an airport runway; the position forming mechanism enables the radar transmitting unit to transmit radar signals at a fixed preset transmitting position;

the position forming mechanism is also used for bearing the radar receiving unit and fixing the radar receiving unit at a preset receiving position on one side of the airport runway; the position forming mechanism enables the radar receiving unit to receive radar echo signals at a fixed preset receiving position.

In the embodiment of the disclosure, the radar transmitting unit and the radar receiving unit can be integrated into an integrated radar, and for the integrated radar, the number of the radar transmitting unit and the number of the radar receiving units are the same, and the radar transmitting unit and the radar receiving units are arranged at the same position of the radar array.

In the embodiment of the present disclosure, the radar may also be a transceiver-separated radar, that is, a radar transmitting unit and a radar receiving unit included in the radar are separately disposed. When the radar works in a continuous wave mode, the receiving and transmitting separated radar can effectively inhibit the problem that a transmitter interferes with a receiver. The receiving and transmitting separated radar can work in a pulse mode and can also work in a continuous wave mode. For the send-receive separated radar, there may be multiple implementations, for example, in the case that the radar transmitting unit and the radar receiving unit are both configured to be disposed on both sides of the airport runway, the radar transmitting unit and the radar receiving unit are both configured to be disposed along the same side or different sides of the airport runway.

In the embodiment of the disclosure, the radar transmitting unit and the radar receiving unit can be respectively arranged on the connecting and rotating mechanism and can rotate through the rotation of the connecting and rotating mechanism, and the connecting and rotating mechanism can be arranged on the supporting structure. Wherein, it can drive radar emission unit and/or radar receiving element rotatable to connect with slewing mechanism, certainly, connect with slewing mechanism also can not rotate so that radar emission unit and/or radar receiving element irrotational. The support structure can be fixedly arranged on any side of the airport runway according to the actual application requirement.

In the embodiment of the present disclosure, the radar transmitting unit and the radar receiving unit structurally belong to the same structural body, or belong to different structural bodies.

In one embodiment, when the radar transmitting unit and the radar receiving unit belong to the same structural body in structure, the transmission and reception of signals can be realized through the same structural body.

In another embodiment, when the radar transmitting unit and the radar receiving unit belong to different structural bodies structurally, the signals need to be transmitted and received through the different structural bodies.

In the embodiment of the disclosure, the radar transmitting unit comprises a radar transmitter and a radar transmitting antenna, and the radar receiving unit comprises a radar receiving antenna, a radar receiver, a radar data acquisition unit and a radar data recording unit. The radar transmitter is configured to generate a transmit signal and the radar receiver is configured to receive a radar return signal. The radar transmitting antenna is configured to convert the electrical signal into a spatial electromagnetic wave to be transmitted to the detection area. The radar receiving antenna is configured to convert the spatial electromagnetic waves scattered back by the detection area into electrical signals. It can be understood that when the radar is a receiving and transmitting integrated radar, the transmitting antenna and the receiving antenna can be configured to be the same antenna or the same antenna array, and the radar works in a pulse mode; it is also possible to use two antennas, one for transmitting and the other for receiving, the radar operating in continuous wave mode. Wherein the detection area is a part-area of an airport runway.

In the embodiment of the disclosure, the radar data acquisition unit and the radar data recording unit are arranged in parallel. The radar data acquisition unit can be configured to digitize echo signals obtained from different positions to obtain radar echo data. The radar data recording unit may be configured to store radar echo data and motion attitude information obtained at different locations. Here, the motion attitude information may be used to indicate radar angle data or the like.

In embodiments of the present disclosure, the array radar foreign object detection system may further include a controller, which may be configured to control and monitor system operation. For example, the controller may be configured to send a radar rotation control command to the radar, the radar rotation control command instructing the radar-emitting unit and/or the radar-receiving unit to rotate.

In the embodiment of the present disclosure, the types of the foreign matters include, but are not limited to: metal parts (such as nuts, screws, gaskets, nails, fuses and the like) in the detection area on the land, mechanical tools, concrete asphalt fragments (such as stones, sand, ice slag and the like), flying animals, articles which are easy to carry in the airplane (such as personal articles, pens, pencils, buttons and the like) and the like have safety influence on moving objects needing to move in the detection area.

In the embodiment of the present disclosure, the position forming mechanism includes a plurality of structural units, and each structural unit includes a connection and rotation mechanism, a movement posture measurement unit, and a support structure.

In the embodiment of the disclosure, the position forming mechanism is used for realizing the measurement of the supporting, rotating and moving postures of the radar.

In the embodiment of the present disclosure, the plurality of radar receiving units 201, 202, ·,20j,20n are respectively configured to receive echo signals obtained by scattering and/or reflecting radar detection signals transmitted by the plurality of radar transmitting units 101, 102, ·,10i,10m, where, regarding that i is equal to or not equal to j, n is equal to or not equal to m, and i, j, m, n belong to natural numbers.

In the embodiment of the disclosure, the radar arrays disposed on two opposite sides or one side of the detection area (airport runway) are mainly used for imaging, so as to obtain the effect of high azimuth resolution.

In imaging applications to the earth, synthetic aperture radars are typically employed for imaging: the synthetic aperture radar requires a flight system, such as an airplane or a satellite, to be provided with a radar, and during a flight, a beam emitted from an antenna of the radar covers a band on the ground, and then receives scattered or reflected waves of a ground object on the band, thereby forming an image. And the integration of a plurality of images improves the resolution. In the embodiment of the disclosure, because the detection area is about the airport runway, it is necessary to avoid that other flight systems influence the normal aircraft, and if the synthetic aperture radar loaded by the flight system is used, the safety of the aircraft, personnel, airport equipment and the like is potentially influenced, so that the radar transmitting array or the radar receiving array which is fixedly arranged is arranged in the method, a data acquisition process similar to the synthetic aperture radar is performed, and the influence on the safety of the aircraft, personnel, vehicles, equipment and the like in the airport is reduced while the effect of high azimuth resolution is obtained through imaging processing.

In the embodiment of the present disclosure, the preset first-type positions and the preset second-type positions are distributed on two opposite sides of the detection area.

In the embodiment of the present disclosure, the preset first-type positions and the preset second-type positions may also be distributed on the same side of the detection area.

In the embodiment of the disclosure, the distance between the preset first-class positions is less than or equal to a first threshold distance; the distance between the preset second-type positions is smaller than or equal to a second threshold distance. The first threshold distance is less than or equal to an imaging resolution; the second threshold distance is smaller than or equal to the length of the short-distance end of the detection area irradiated by the beams of two adjacent radars.

In the embodiment of the disclosure, after the plurality of radar transmitting units transmit radar detection signals to the detection area, the plurality of radar receiving units may receive echo signals obtained by scattering and/or reflecting the detection signals by targets or clutter, and here, regarding the relative position relationship between the plurality of radar transmitting units and the plurality of radar receiving units, the imaging resolution of the radar needs not to be affected.

In the embodiment of the present disclosure, regarding the size of the interval, the equivalent spatial sampling interval synthesized by the radar transmitting unit and the radar receiving unit needs to be less than or equal to the imaging resolution.

When radar transmitting unit and radar receiving element are in same position, radar adopts the integrative radar of receiving and dispatching promptly, and radar transmitting unit and radar receiving element constitute radar receiving and dispatching unit, and the interval between every radar receiving and dispatching unit needs be less than or equal to the formation of image resolution ratio.

When the radar transmitting unit and the radar receiving unit are separated, the interval between the radar transmitting units can meet a first threshold distance, and the interval between the radar receiving units can meet a second threshold distance; or the interval between the radar transmitting units meets the second threshold distance, and the interval between the radar receiving units meets the first threshold distance.

In the embodiments of the present disclosure, the radar transmitting unit or the radar receiving unit may adopt different beam widths. One is a first radar beam with a beam coverage area of all of the airport runways; and the other is a second radar beam, wherein the beam coverage area of the second radar beam is part of the airport runway.

In the embodiment of the disclosure, as shown in fig. 2, when the radar transmitting unit and the radar receiving unit of the embodiment are in the same position, that is, the radar adopts a radar which integrates transmitting and receiving, and the radar transmitting unit and the radar receiving unit constitute a radar transmitting and receiving unit, so that the radar receiving unit can receive an echo signal obtained by scattering and/or reflecting a radar detection signal transmitted by the corresponding radar transmitting unit by a target or a clutter. The interval between each radar transceiver unit needs to be less than or equal to the imaging resolution, that is, the position relationship between the radar transceiver units is the first kind of position.

In the embodiment of the present disclosure, as shown in fig. 3, the radar transmitting unit and the radar receiving unit are distributed on two opposite sides of the detection area;

the position relation among the radar transmitting units is the second type of position, and the position relation among the radar receiving units is the first type of position.

The distance between two adjacent radar transmitting units is smaller than or equal to the short-distance end width of an irradiation detection area corresponding to beams transmitted by the two adjacent radar transmitting units, and the distance between the plurality of radar receiving units is smaller than or equal to imaging resolution; or equivalent phase centers formed by the radar transmitting units and the corresponding radar receiving units, and the interval between adjacent equivalent phase centers is smaller than or equal to the imaging resolution.

In the embodiment of the present disclosure, the radar transmitting units and the radar receiving units are distributed on two opposite sides of the detection area, so that the plurality of radar transmitting units at the preset positions and the plurality of radar receiving units at the preset positions are located on the opposite sides of the detection area.

In the embodiment of the present disclosure, the radar transmitting units and the radar receiving units may also be distributed on the same side of the detection area, so that the plurality of preset radar transmitting units and the plurality of preset radar receiving units are located on the same side of the detection area.

In the embodiment of the disclosure, the distance between two adjacent radar transmitting units is greater than the distance between two adjacent radar receiving units; the position relation among the radar transmitting unit arrays on one side where the plurality of radar transmitting units are located meets the second type of position; the positional relationship between the radar receiving units satisfies the first kind of positions.

In the embodiment of the present disclosure, the radar transmitting unit and the radar receiving unit may also be located on the same side of the detection area, and when the radar transmitting unit and the radar receiving unit are located on the same side of the detection area, although the number of the radar transmitting units is less than that of the radar receiving units at this time, the radar transmitting unit and the radar receiving unit at corresponding positions may still be placed at the same position, and a distance between two adjacent radar transmitting units is still greater than a distance between two adjacent radar receiving units; the distance between two adjacent radar receiving units is still smaller than or equal to the imaging resolution.

In the embodiment of the present disclosure, the short-distance end of the detection area irradiated by the beam of the radar transmitting unit refers to the short-distance end of the detection area irradiated by the beam of the radar transmitting unit, and the like.

In the embodiment of the disclosure, the airport runway is irradiated by radar detection signals transmitted by a plurality of radar transmitting units, and meanwhile, the scattering signals of radar detection areas are received by a plurality of radar receiving units, so that radar echo data are obtained, and radar echo data are subjected to imaging processing to obtain radar images.

In the embodiment of the disclosure, through the above arrangement and placement between the radar transmitting unit and the radar receiving unit, the relation between the radar number and the sampling interval required by the radar resolution can be properly balanced, so that the number of the radar transmitting units can be properly reduced, and the sampling interval required by the high radar resolution can also be provided.

In the embodiment of the present disclosure, as shown in fig. 4, the radar transmitting unit and the radar receiving unit are distributed on two opposite sides of the detection area;

the position relation among the radar transmitting units is a first position, and the position relation among the radar receiving units is a second position.

The distance between two adjacent radar receiving units is smaller than or equal to the short-range end width of a detection area corresponding to the wave beams of the two adjacent radar receiving units, and the distance between the multiple radar transmitting units is smaller than or equal to the imaging resolution; or the radar transmitting units and the corresponding radar receiving units form equivalent phase centers, and the interval between adjacent equivalent phase centers is smaller than or equal to the imaging resolution.

In the embodiment of the present disclosure, the radar transmitting units and the radar receiving units are distributed on two opposite sides of the detection area, so that the plurality of preset radar transmitting units and the plurality of preset radar receiving units are located on the opposite sides of the detection area.

In the embodiment of the present disclosure, the radar transmitting unit and the radar receiving unit may also be distributed on the same side of the detection area, so that the plurality of preset transmitting units and the plurality of radar receiving units at the preset position are located on the same side of the detection area.

In the embodiment of the disclosure, the distance between two adjacent radar transmitting units is greater than the distance between two adjacent radar receiving units; the position relation among the radar transmitting unit arrays on one side where the plurality of radar transmitting units are located meets the first class position; the positional relationship between the radar receiving units satisfies the second type of position.

In the embodiment of the present disclosure, the radar transmitting unit and the radar receiving unit may also be located on the same side of the detection area, and when the radar transmitting unit and the radar receiving unit are located on the same side of the detection area, although the number of the radar receiving units is less than that of the radar transmitting units at this time, the radar receiving unit and the radar transmitting unit at corresponding positions may still be placed at the same position, and a distance between two adjacent radar receiving units is still greater than a distance between two adjacent radar transmitting units; the distance between the two adjacent radar transmitting units is still smaller than or equal to the imaging resolution.

In the embodiment of the disclosure, through the above arrangement and placement between the radar transmitting unit and the radar receiving unit, the relation between the radar number and the sampling interval required by the radar resolution can be properly balanced, so that the number of the radar receiving units can be properly reduced, and the sampling interval required by the high radar resolution can also be provided.

In the embodiment of the present disclosure, as shown in fig. 5, the radar transmitting unit and the radar receiving unit are distributed on two opposite sides of the detection area. The radar transmitting unit and the radar receiving unit can also be distributed on the same side of the detection area.

The distance between two adjacent radar transmitting units is larger than the distance between two adjacent radar receiving units;

the total length of the plurality of radar receiving units is not less than the interval between the array elements of the radar transmitting array, and the interval between the array elements of the radar transmitting array is not more than the width of the near end of the irradiation runway corresponding to the antenna beam of the array element; the number of the radar receiving units meets the condition that the number of the radar receiving units is multiplied by the distance between two adjacent radar receiving units, and the distance between the two adjacent radar receiving units is larger than the width of a long-distance end of an irradiation detection area corresponding to the wave beams of two adjacent radar transmitting units.

The radar receiving unit and the corresponding radar transmitting unit form an equivalent phase center, and the distance between two adjacent equivalent phase centers is smaller than or equal to the imaging resolution.

In the embodiment of the disclosure, the multiple radar receiving units may receive, by rotating the receiving beam direction, the multiple echo signals obtained by scattering and/or reflecting the radar detection signals transmitted by the sending radar by the target or the clutter.

In the embodiment of the disclosure, the radar receiving unit is smaller than the radar transmitting unit in distance, the number of the radar receiving unit and the number of the radar receiving unit can be effectively reduced through the combination of the radar transmitting unit and the radar receiving unit, the resolution can be improved through imaging, and the scale of a radar system is reduced.

In the embodiment of the present disclosure, as shown in fig. 6, the radar transmitting unit and the radar receiving unit are distributed on two opposite sides of the detection area. The radar transmitting unit and the radar receiving unit can also be distributed on the same side of the detection area.

The distance between two adjacent radar transmitting units is smaller than the distance between two adjacent radar receiving units;

the total length of the plurality of radar transmitting units is not less than the interval between the array elements of the radar receiving array, and the interval between the array elements of the radar receiving array is not more than the width of a near end of an irradiation runway corresponding to the antenna wave beam of the array element; the number of the radar transmitting units meets the condition that the number of the radar transmitting units is multiplied by the distance between two adjacent radar transmitting units, and the distance between the two adjacent radar transmitting units is larger than the width of a long-distance end of a detection area corresponding to the wave beams of two adjacent radar receiving units.

In the embodiment of the disclosure, the plurality of radar receiving units may cover all detection areas (all runway areas) by rotating the direction of the transmitted beam, and the plurality of radar receiving units may receive echo signals obtained by scattering and/or reflecting a plurality of radar detection signals transmitted by the transmitting radar by a target or a clutter.

In the embodiment of the disclosure, the number of the radar transmitting units is less than that of the radar receiving units, and the number of the radar receiving units can be effectively reduced through the combination of the radar transmitting units and the radar receiving units, so that the resolution can be improved through imaging, and the scale of a radar system is reduced.

In the embodiment of the present disclosure, as shown in fig. 7, the radar transmitting unit 10i at least includes: a radar transmitter 10i01 and a radar transmitting antenna 10i02;

the radar transmitter 10i01 is connected with the radar transmitting antenna 10i02, and the radar transmitter 10i01 is used for generating and amplifying a transmitting electric signal and transmitting the transmitting electric signal to the radar transmitting antenna 10i02;

the radar transmitting antenna 10i02 is configured to convert the transmitting electrical signal into a radar electromagnetic wave, and transmit the radar electromagnetic wave to a detection area.

In the embodiment of the present disclosure, the radar transmission antenna 10i02 is configured to convert a transmission electric signal into a radar detection signal in the form of an electromagnetic wave at different positions and transmit the radar detection signal to a detection area.

In the embodiment of the disclosure, the plurality of radar transmitting units correspond to the plurality of radar transmitters and the plurality of radar transmitting antennas, and the transmitting antenna array formed by the plurality of radar transmitting antennas can transmit the plurality of radar detection signals to the detection area.

In the embodiment of the present disclosure, as shown in fig. 7, the radar receiving unit 20j at least includes: the radar receiving antenna 20j01, the radar receiver 20j02, the radar data acquisition unit 20j03 and the radar data recording unit 20j04;

the radar receiving antenna 20j01 is connected to the radar receiver 20j02, and the radar receiving antenna 20j01 is configured to receive an echo signal obtained by scattering and/or reflecting the detection signal by a target or a clutter, convert the echo signal into a received electrical signal, and transmit the received electrical signal to the radar receiver 20j02.

In the embodiment of the disclosure, the echo signal obtained by scattering and/or reflecting the detection signal by the target or clutter is in an electromagnetic wave form, the echo signal is received by the plurality of receiving antennas at different positions, the echo signal in the electromagnetic wave form is converted into a receiving electric signal, and the receiving electric signal is transmitted to the signal receiver.

In the embodiment of the disclosure, the plurality of radar receiving units correspond to the plurality of radar receiving antennas and the plurality of radar receiving antennas, a receiving antenna array composed of the plurality of radar receiving antennas receives an echo signal, the echo signal is acquired by a radar data acquisition unit 20j03 through a signal receiver to obtain radar echo data, and a radar data recording unit 20j04 records the radar echo in real time; in addition, the received and acquired multiple radar echo data are sent to the radar imaging unit 300 for high-resolution imaging.

In the embodiment of the disclosure, no matter the radar transmitting unit or the radar receiving unit, a certain rotation angle can be provided, and the radar transmitting unit or the radar receiving unit needs to be installed on the connecting and rotating mechanism, and the connecting and rotating mechanism adjusts the direction of the radar transmitting beam or the radar receiving beam by driving a part of the rotating radar or the radar to rotate;

the radar also needs to be connected with an attitude measurement unit for measuring angle data of the connection and rotation mechanism, and then determining the direction of a radar transmitting beam or the direction of a receiving beam;

a support structure configured for supporting the connection and rotation mechanism and/or the radar transmitting unit or/and the radar receiving unit;

and the controller is used for controlling and monitoring the operation of the array radar foreign matter detection system.

In an embodiment of the present disclosure, with reference to fig. 8, there is provided an array radar foreign object detection method, including:

step S901, forming a transmitting array by a plurality of radar transmitting units arranged at preset positions, and transmitting a radar detection signal to a detection area;

step S902, forming a receiving array by a plurality of radar receiving units arranged at preset positions, and receiving echo signals obtained by scattering and/or reflecting the detection signals by targets or clutter;

step S903, acquiring the echo signal to obtain radar echo data, and performing imaging processing on the radar echo data to obtain a radar image in the detection area;

and step S904, detecting foreign matters according to the radar image in the detection area, and determining whether foreign matters exist in the detection area.

In the embodiment of the present disclosure, in the signal transmission between step S901 and step S904, a plurality of radar detection signals formed by the detection signals transmitted by a plurality of radar transmitting units cover a plurality of strips in a detection area, a plurality of radar receiving units receive echo signals obtained by scattering and/or reflecting targets or clutter in the detection area on a plurality of corresponding strips, acquire a plurality of radar echo data, and transmit the radar echo data to a radar imaging unit for image processing to form a high-resolution radar image.

In the embodiment of the present disclosure, as shown in fig. 9, the radar transmitting unit at least includes: the radar transmitter comprises a signal generating and signal amplifying circuit, and the transmitting signal generator is connected with the radar transmitting antenna;

step S901, transmitting a plurality of radar detection signals to a detection area through a plurality of radar transmission units arranged at preset positions, including:

step S9011, generating a transmitting electric signal through the radar transmitter, amplifying the transmitting signal, and transmitting the transmitting electric signal to the radar transmitting antenna;

and step S9012, converting the transmitting electric signal into an electromagnetic wave through the radar transmitting antenna, and transmitting the electromagnetic wave to a detection area.

In an embodiment of the present disclosure, the radar receiving unit at least includes: the radar receiving antenna is connected with the radar receiver;

the method further comprises the following steps:

and receiving an echo signal obtained by scattering and/or reflecting the detection signal by a target or clutter through the radar receiving antenna, converting the echo signal into a receiving electric signal, and transmitting the receiving electric signal to the radar receiving antenna.

Referring to fig. 11, in an array radar foreign object detection system according to an embodiment of the present disclosure, the array radar foreign object detection system may include: the device comprises a radar transmitter, a radar receiver, a radar antenna array, a radar data acquisition unit, a radar data processing unit, a radar data recording unit, a connecting and rotating mechanism, a motion attitude measuring unit, a supporting structure, a controller and the like.

In connection with the above embodiments, the following examples are provided for further illustration:

in an embodiment of the present disclosure, an array radar foreign object detection system includes:

a radar transmitter: configured to generate a transmit signal; a radar receiver: configured to receive a radar echo signal; a radar array: the combination of the plurality of radar transmitting antennas and the plurality of radar receiving antennas is configured to convert the electric signals into space electromagnetic waves at different positions and transmit the space electromagnetic waves to a detection area, or convert the space electromagnetic waves scattered by targets or clutter in the detection area into the electric signals at different positions; radar data acquisition unit: the radar echo acquisition device is configured to digitize echo signals obtained from different positions to obtain radar echo data; a radar imaging unit: the radar imaging device is configured to perform imaging processing on echo data obtained from different positions to obtain a radar image; a radar image detection unit configured to perform runway foreign object detection processing using a radar image; radar data recording unit: configured to store radar echo data and motion attitude information obtained at different locations; a connection and rotation mechanism configured to mount the radar transmitting unit and the radar receiving unit, connect, carry and rotate the radar or a portion of the radar; an attitude measurement unit configured to measure angle data of the connection and rotation mechanism; a support structure configured to support the coupling and rotation mechanism; a controller configured to control and monitor system operation.

The number of the components of the detection system can be one or more than one.

The supporting structure is of a steel beam structure, or a reinforced concrete structure, or a structure combining reinforced concrete and a steel beam.

Referring to fig. 2, a method for detecting array foreign objects according to an embodiment of the present invention is further described. The array radar foreign matter detection method comprises the following steps:

the radar arrays are arranged along the set positions on one side or two sides of the airport runway;

a transmitting part of the radar array transmits a detection signal to the ground to be detected;

a receiving part of the radar array receives an echo signal scattered by the ground to be detected;

performing imaging processing by using echo signals obtained by the radar array at different positions to obtain a radar image of a detection area;

and detecting foreign matters in the radar image, and judging whether foreign matters exist in the runway or not.

It can also be seen from the schematic diagram that, because the runway is imaged, the narrow beam adopted by the existing millimeter wave FOD detection radar is not needed, although the method of the present invention adopts the microwave band with good weather adaptability and detects with the wide beam, the area of the resolution unit can be reduced after the data collected at different positions are imaged, so that the clutter intensity is reduced in several orders, and the detection performance is improved.

For the array radar foreign object detection method of fig. 2, the radar array is arranged along one side of the airport runway, and the transmitting part and the receiving part of each array element of the radar array are at the same position.

Each array element of the radar array is placed according to a set position, the interval between the position points of each array element is set according to the imaging resolution, according to the difference of the radar array imaging detection system, the interval is not greater than the imaging resolution, or the interval of the equivalent phase centers formed by the transmitting part and the receiving part is not greater than the imaging resolution.

The imaging processing is carried out on the echo signals obtained by each array element of the radar array at different positions, the echo signals obtained at different positions are equivalent to the echo signals acquired by the synthetic aperture radar at different positions in the air movement process, and then the imaging processing is carried out by means of the imaging processing method of the synthetic aperture radar.

A method for detecting foreign objects in a transmit-receive split array radar according to an embodiment of the present invention is further described with reference to fig. 3.

Divide into radar emission array and radar receiving array part with the radar array, radar emission array sparse distribution is in one side along the runway, and radar receiving array dense distribution is in one side along the runway, and the interval between the array element of radar receiving array is not more than the imaging resolution ratio, and the interval between the array element of radar emission array is not more than the short-range end width of the irradiation runway that the wave beam corresponds.

According to the imaging detection method, radar detection signals emitted by each array element of the radar emitting array irradiate a radar runway, meanwhile, radar receiving units of the radar receiving array receive radar scattering signals in an irradiation area of the radar detection signals, collect the signals to obtain corresponding echo data, and perform imaging processing on the echo data to obtain radar images.

In fig. 3, the radar transmitting array and the radar receiving array are respectively arranged on two sides of the runway, and the radar transmitting array and the radar receiving array can also be arranged on one side of the runway. When the radar transmitting array and the radar receiving array are arranged on one side of the runway, a certain array element of the radar transmitting array and an array element of the radar receiving array at a corresponding position can be placed at the same position.

For the imaging detection method, the positions of the radar receiving array and the radar transmitting array can be interchanged. Fig. 4 can be seen as a schematic diagram illustrating the exchange of transmitting and receiving in the method for detecting foreign object in the transmit/receive split array radar according to the embodiment of fig. 3.

Referring to fig. 5, a schematic diagram of another method for detecting foreign objects in a transmit-receive split array radar according to an embodiment of the present invention is further illustrated. Divide into radar array and radar receiving array part with radar array, radar transmitting array sparse distribution is in the one side along the runway, radar receiving array dense distribution is in the one side along the runway, interval between the array element of radar receiving array is not more than the formation of image resolution ratio, the total length of radar receiving array is not less than the interval between the array element of radar transmitting array, interval between the array element of radar transmitting array is not more than the short-range end width of the illumination runway that the antenna beam of array element corresponds, the array element of radar receiving array and the receiving and dispatching combination that the array element of radar transmitting array formed correspond equivalent phase center, interval between the adjacent equivalent phase center is not more than the formation of image resolution ratio. The number of the radar receiving units meets the condition that the number of the radar receiving units is multiplied by the distance between two adjacent radar receiving units, and the distance between the two adjacent radar receiving units is larger than the width of a long-distance end of an irradiated detection area corresponding to the wave beams of two adjacent radar transmitting units.

According to the imaging detection method, radar detection signals respectively emitted by each array element of a radar emission array irradiate a radar runway, meanwhile, the array elements of a radar receiving array receive radar scattering signals in a radar emission array beam irradiation area, the signals are collected to obtain echo data corresponding to the equivalent phase center of a corresponding receiving and transmitting combination, imaging processing is carried out on the echo data which correspond to the equivalent phase center of the receiving and transmitting combination formed by the array elements of all the radar receiving arrays and the array elements of the radar emission array, and radar images are obtained.

In fig. 5, the radar transmitting array and the radar receiving array are respectively arranged on two sides of the runway, and the radar transmitting array and the radar receiving array can also be arranged on one side of the runway. When the radar transmitting array and the radar receiving array are arranged on one side of the runway, a certain array element of the radar transmitting array and an array element of the radar receiving array at a corresponding position can be placed at the same position. The radar receiving array can be placed at one end of the length direction of the runway, or placed in the center of the length direction of the runway.

For this imaging detection method, the positions of the radar receiving section and the radar transmitting section may also be interchanged. Fig. 6 can be regarded as a schematic diagram of the exchange of transmission and reception of the foreign object detection method of the array radar with separate transmission and reception according to the embodiment of fig. 5 of the present invention.

In combination with the array radar foreign matter detection system of the present invention shown in fig. 2, fig. 12 is a structural diagram of an array composition of an array radar foreign matter detection system according to an embodiment of the present invention, in which a radar transmitter, a radar receiver, a radar antenna, and a radar data acquisition unit constitute a radar transceiving array element, the radar transceiving array element, a motion attitude measurement unit, a connection and rotation mechanism, and a support structure constitute a structure, a plurality of structures constitute a linear array, and in combination with an actual layout situation in an airport, the linear array is placed on one side of a runway, is parallel to the runway, and is spaced from the runway by a certain distance, and the radar transceiving array element is higher than a horizontal plane of the runway. The radar imaging unit, the radar data recording unit and the controller can be placed in one of the structures according to actual conditions or split into a plurality of parts. The system is provided with 1,2, N radar transmitting and receiving array elements and 1,2, N structural bodies. N is a natural number.

As for fig. 3, 4, 5 and 6, fig. 13 is a structural composition diagram of an array foreign matter detection system of the present invention, in which a radar transmitter and a radar antenna form a radar transmitting array element, and a radar receiver, a radar antenna and a radar data acquisition unit form a radar receiving array element; the system comprises 1,2, M radar transmitting array elements and 1,2, N radar receiving array elements; n and M are natural numbers.

The radar transmitting array element and the moving attitude measuring unit, the connecting and rotating mechanism and the supporting structure form a transmitting structure body, and the radar receiving array element and the moving attitude measuring unit, the connecting and rotating mechanism and the supporting structure form a receiving structure body; there are 1,2, M transmitting structures and 1,2, N receiving structures; n and M are natural numbers.

The plurality of transmitting structure bodies form a transmitting linear array, the transmitting linear array is placed on one side of the runway in combination with the actual layout condition in the airport, the transmitting linear array is parallel to the runway and is spaced from the runway by a certain distance, and the radar transmitting array elements are higher than the horizontal plane of the runway;

the receiving linear array is arranged on one side of the runway in combination with the actual layout condition in the airport, the receiving linear array is parallel to the runway and is spaced from the runway by a certain distance, and the radar receiving array element is higher than the horizontal plane of the runway;

the transmitting linear array and the receiving linear array can be on the same side of the runway or opposite to the runway;

the radar imaging unit and the radar data recording unit can be placed in one receiving structure body according to actual conditions or can be split into a plurality of parts to be placed;

the controller can be placed in one of the receiving structures or the transmitting structure according to actual conditions, or be split into a plurality of parts.

The above description is only for the specific embodiments of the present disclosure, but the scope of the present disclosure is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present disclosure, and all the changes or substitutions should be covered within the scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope of the claims.

Claims

1. An array radar foreign object detection system comprising a radar and a position forming mechanism, the radar comprising:

the radar transmitting units are respectively arranged at the preset positions of the transmitting units to form a transmitting array and used for transmitting radar detection signals to the detection area;

the radar receiving units are respectively arranged at the preset positions of the receiving units to form a receiving array and are used for receiving echo signals obtained by scattering and/or reflecting the detection signals by targets or clutter;

the radar imaging unit is used for carrying out imaging processing on the basis of the received echo signals of the multiple positions and generating a radar image of the detection area;

a radar image detection unit for detecting whether a foreign object exists in a radar image of the detection area;

the position forming mechanism is used for bearing the radar transmitting unit and fixing the radar transmitting unit at a preset transmitting position on one side of the airport runway; the position forming mechanism enables the radar transmitting unit to transmit radar signals at a fixed preset transmitting position;

2. The system of claim 1, wherein the radar-transmitting unit and the radar-receiving unit are structurally of the same structure or of different structures.

3. The system of claim 1, wherein the radar transmission unit comprises a radar transmitter and a radar transmission antenna, and the radar reception unit comprises a radar reception antenna, a radar receiver, a radar data acquisition unit, and a radar data recording unit.

4. The system of claim 1, wherein the position forming mechanism comprises a plurality of structural units, each structural unit comprising a connection and rotation mechanism, a motion attitude measurement unit, a support structure.

5. The array radar foreign object detection system of claim 1, wherein one way of the radar transmitting unit preset position and the radar receiving unit preset position is: are located on the same side of the detection zone; the distance between any two radar transmitting units is smaller than or equal to the imaging resolution, or/and the distance between any two radar receiving units is smaller than or equal to the imaging resolution.

6. The array radar foreign object detection system of claim 1, wherein another way of the radar transmitting unit preset position and the radar receiving unit preset position is: distributed on opposite sides of the detection region; and the distance between any two radar transmitting units is smaller than or equal to the imaging resolution, or/and the distance between any two radar transmitting units is smaller than or equal to the imaging resolution.

7. The array radar foreign object detection system of claim 1, wherein another way of presetting the position of the radar receiving unit is: when the distance between any two radar transmitting units is smaller than or equal to the imaging resolution, the distance between two adjacent radar receiving units is larger than the distance between two adjacent radar transmitting units, and the distance between two adjacent radar receiving units is smaller than or equal to the short-range end width of a detection area corresponding to the wave beam of the radar receiving unit.

8. The array radar foreign object detection system of claim 7, wherein the number of the radar transmitting units is larger than the distance end width of the detection area corresponding to the beams of two adjacent radar receiving units, which is obtained by multiplying the number of the radar transmitting units by the distance between two adjacent radar transmitting units.

9. The array radar foreign object detection system of claim 1, wherein another way of presetting the position of the radar transmission unit is: when the distance between any two radar receiving units is smaller than or equal to the imaging resolution, the distance between two adjacent radar transmitting units is larger than the distance between two adjacent radar receiving units, and the distance between two adjacent radar transmitting units is smaller than or equal to the short-range end width of an irradiation detection area corresponding to the beams transmitted by the two adjacent radar transmitting units.

10. The array radar foreign object detection system of claim 9, wherein the number of the radar receiving units is larger than the distance end width of the irradiation detection area corresponding to the beams emitted by two adjacent radar emitting units, which is obtained by multiplying the number of the radar receiving units by the distance between two adjacent radar receiving units.

11. An array radar foreign object detection method, the method comprising:

the radar transmitting unit and the radar receiving unit are arranged along the preset positions on one side or two sides of the airport runway;

the radar transmitting unit transmits radar detection signals to a detection area on an airport runway at a plurality of preset transmitting positions;

the radar receiving unit receives echo signals scattered by the radar detection signals acting on the detection area at a plurality of preset receiving positions;

the radar imaging unit carries out imaging processing by using echo signals corresponding to the transceiving combinations of different preset transmitting positions and preset receiving positions to obtain a radar image of a detection area;

the radar image detection unit detects foreign matters by utilizing radar images and detects whether foreign matters exist in a detection area.

12. The method according to claim 11, wherein the transmitting of the radar detection signal to the detection area on the airport runway is performed by adjusting a radar transmission beam direction of a radar transmission antenna of a radar transmission unit using the connecting and rotating mechanism of the moving position forming mechanism so that the radar transmission beam is irradiated to the detection area on the airport runway.

13. The method according to claim 11, wherein the receiving of the echo signal scattered by the radar detection signal acting on the detection area is performed by adjusting a radar receiving beam direction of a radar receiving antenna of a radar receiving unit by using a connecting and rotating mechanism of a position forming mechanism so that the radar receiving beam covers the detection area on the airport runway.

14. The method of claim 11, wherein the predetermined launch location is a fixed location at which a support structure of the position forming mechanism is located when the predetermined launch location is on either side of an airport runway;

the predetermined receiving position is a fixed position in which a support structure of the position forming mechanism is located when the predetermined receiving position is located on either side of the airport runway.

15. The method of claim 14, wherein the fixed locations are located on either side of an airport runway along a line drawn from the fixed location to an adjacent fixed location, the line combining into a straight line or a polyline.