Ground verification method and device for depth detection performance of asteroid detection radar

Abstract

The invention provides a ground verification method and device for depth detection performance of an asteroid detection radar, relates to the technical field of depth detection of the asteroid detection radar, and aims to solve the technical problem that the actual detection performance of the radar cannot be accurately evaluated due to the lack of a verification method for the depth detection performance of the asteroid detection radar in the prior art. The method comprises the steps of obtaining a first echo signal-to-noise ratio (simulation signal-to-noise ratio) meeting the depth detection performance of the asteroid detection radar through a simulation model, obtaining a second echo signal-to-noise ratio (actual signal-to-noise ratio) of actual detection through the unmanned aerial vehicle hanging the asteroid detection radar, and comparing and analyzing the result difference between the simulation signal-to-noise ratio and the actual signal-to-noise ratio. And verifying and evaluating the depth detection capability of the asteroid detection radar. The ground verification method and device can be successfully applied to scientific verification test and scientific realizability evaluation of an asteroid detection radar, and are beneficial to supporting load development and application work of a Tianzhou No.2 detection task.

Description

Technical Field

[0001] The present invention relates to the field of asteroid detection radar depth detection technology, and more specifically, to a ground verification method and device for the depth detection performance of an asteroid detection radar. Background Art

[0002] The asteroid sounding radar is one of the important payloads of the Tianwen-2 exploration mission. It is used to obtain surface and subsurface radar echo data of the near-Earth asteroid 2016HO3 (Kamo'oalewa, Oscillating Star) and the main-belt comet 311P / (2013 P5) PANSTARRS (Panoramic Survey Telescope And Rapid Response System, Pan-STARRS), conduct sub-surface structure detection of asteroids and comets, and provide scientific detection data for cutting-edge scientific research on the origin and evolution of small celestial bodies.

[0003] When the asteroid detection radar flies around an asteroid or comet, it hovers at an appropriate time and transmits electromagnetic wave signals to the underground of the detection body. The electromagnetic wave signals propagate in the underground medium and produce reflection and scattering of electromagnetic waves when encountering targets such as soil stratification, ice layer, and rock. The radar signal is reflected by the surface of the asteroid to form a surface echo. The radar signal undergoes surface transmission, surface attenuation, and subsurface reflection to form a subsurface echo. The subsurface echo has an additional delay compared to the surface echo. The complete echo data of the orbiting detection is received by the rotation of the asteroid. By processing the radar echo, the depth information of the target with discontinuous underground electromagnetic parameters can be obtained, and scientific goals such as the detection of the internal structure of asteroids / comets and the inversion of dielectric constants can be completed.

[0004] The ultimate performance indicators of the asteroid detection radar will be reflected in two aspects: detection depth and resolution. In order to verify whether the asteroid detection radar can meet the index requirements in engineering missions, it is necessary to evaluate the depth detection capability of the asteroid detection radar through ground tests. Since the asteroid detection radar is my country's first small celestial body orbiting and penetrating detection radar, it is impossible to directly obtain the detection depth by detecting underground targets. It adopts a unique hovering orbit and relies on the rotation of the small celestial body for detection. However, there is currently a lack of mature ground detection depth verification methods available. Summary of the invention

[0005] In view of this, the present invention provides a ground verification method and device for the deep detection performance of an asteroid detection radar, so as to solve the technical problem that the actual detection performance of the radar cannot be accurately evaluated due to the lack of a verification method for the deep detection performance of an asteroid detection radar in the prior art.

[0006] One aspect of the present invention provides a ground verification method for the deep detection performance of an asteroid detection radar, comprising: generating a standard sphere model according to the attribute information of the target asteroid, wherein the standard sphere model is used to simulate the radar echo characteristics of the target asteroid; based on the standard sphere model, according to the distance resolution unit size and azimuth resolution of different radar detection modes, simulating and obtaining a first radar cross-section parameter corresponding to the minimum resolution unit of the standard sphere model under a metal material; converting the first radar cross-section parameter into a second radar cross-section parameter corresponding to the minimum resolution unit of the standard sphere model under a double-layer medium, wherein the double-layer medium is used to simulate the real geological characteristics of the target asteroid, including a surface medium and a subsurface medium; The minimum resolution unit is used as the verification area, and the third radar scattering cross-section parameters corresponding to the asteroid detection radar in the verification area are simulated according to the preset detection altitude and detection parameters, wherein the verification area is equivalent to a standard plane; the first echo signal-to-noise ratio that meets the depth detection performance of the asteroid detection radar is calculated according to the second radar scattering cross-section parameters and the third radar scattering cross-section parameters; the asteroid detection radar is flown by an unmanned aerial vehicle, and the ground echo data of the verification area under different radar detection modes are obtained based on the same detection altitude and detection parameters, and the second echo signal-to-noise ratio of the actual detection is calculated according to the ground echo data; the depth detection performance of the asteroid detection radar is verified according to the first echo signal-to-noise ratio and the second echo signal-to-noise ratio.

[0007] According to an embodiment of the present invention, based on a standard sphere model, according to the distance resolution unit size and azimuth resolution of different radar detection modes, simulation to obtain a first radar cross-section parameter corresponding to the minimum resolution unit of the standard sphere model under a metal material includes: selecting a corresponding minimum resolution unit on the standard sphere model according to the distance resolution unit size and azimuth resolution of different radar detection modes; establishing an electromagnetic simulation model based on the minimum resolution unit, and setting the material of the standard sphere model to a metal material; and using a finite difference time domain method to simulate and obtain a first radar cross-section parameter corresponding to the minimum resolution unit of the standard sphere model under a metal material.

[0008] According to an embodiment of the present invention, converting a first radar cross section parameter into a second radar cross section parameter corresponding to the minimum resolution unit of a standard sphere model under a double-layer medium includes: obtaining a two-way transmittance-reflectivity product parameter of the target asteroid under real geological characteristics; and calculating the second radar cross section parameter corresponding to the minimum resolution unit of the standard sphere model under a double-layer medium based on the first radar cross section parameter and the two-way transmittance-reflectivity product parameter.

[0009] According to an embodiment of the present invention, the two-way transmittance reflectance product parameter is calculated as follows:

[0010] |T 01 ⋅T10 | 2 |Γ 12 | 2

[0011] Among them, T 01 Indicates the transmittance of vacuum into the surface medium, T 10 represents the transmittance of the surface medium projected into the vacuum, Γ 12 Represents the reflectivity of the surface medium and the subsurface medium.

[0012] According to an embodiment of the present invention, the minimum resolution unit is used as a verification area, and according to preset detection altitude and detection parameters, simulation is performed to obtain the third radar cross-section parameters corresponding to the asteroid detection radar in the verification area, including: establishing a standard plane model of the minimum resolution unit according to ground characteristic information of the minimum resolution unit; and simulating and obtaining the third radar cross-section parameters of the asteroid detection radar in the standard plane model according to the preset detection altitude and detection parameters.

[0013] According to an embodiment of the present invention, utilizing an unmanned aerial vehicle (UAV) to fly an asteroid detection radar and obtaining ground echo data of a verification area under different radar detection modes based on the same detection altitude and detection parameters includes: configuring the UAV flying system; based on the configured UAV flying system, controlling the UAV to arrive at the verification area to collect ground echo data under different radar detection modes according to the detection altitude and detection parameters.

[0014] According to an embodiment of the present invention, the drone flying system includes: onboard equipment, wherein the onboard equipment includes: a radar electronics box, used to generate and receive radar signals; a collector, used to collect, process and package data output by the radar electronics box; a drone flight control and navigation system, used to control the attitude, navigation and flight trajectory planning of the drone, wherein the drone flight control and navigation system is configured with a broadcast function, which can broadcast the flight status of the drone in real time; a first drone data transmission system, used to receive remote control and telemetry instructions from the ground, and to transmit the data output by the radar electronics box.

[0015] According to an embodiment of the present invention, the UAV flight system also includes: a ground station device, wherein the ground station device includes: a remote control and telemetry module, which is used to send and receive remote control and telemetry instructions in real time; a second UAV data transmission system, which is used to perform two-way communication with the first UAV data transmission system through the remote control and telemetry module, and send remote control and telemetry instructions or receive echo data; a control and processing computer, which is used to perform data analysis on the echo data.

[0016] According to an embodiment of the present invention, based on the first echo signal-to-noise ratio and the second echo signal-to-noise ratio, verifying the depth detection performance of the asteroid detection radar includes: in response to the second echo signal-to-noise ratio being greater than or equal to the first echo signal-to-noise ratio, characterizing that the depth detection performance of the asteroid detection radar meets the requirements; in response to the second echo signal-to-noise ratio being less than the first echo signal-to-noise ratio, characterizing that the depth detection performance of the asteroid detection radar does not meet the requirements.

[0017] Another aspect of the present invention provides a ground verification device for the deep detection performance of an asteroid detection radar, the device comprising: a generation module, for generating a standard sphere model according to the attribute information of the target asteroid, wherein the standard sphere model is used to simulate the radar echo characteristics of the target asteroid; a first simulation module, for simulating and obtaining, based on the standard sphere model, a first radar scattering cross-section parameter corresponding to the minimum resolution unit of the standard sphere model under a metal material according to the distance resolution unit size and azimuth resolution of different radar detection modes; a conversion module, for converting the first radar scattering cross-section parameter into a second radar scattering cross-section parameter corresponding to the minimum resolution unit of the standard sphere model under a double-layer medium, wherein the double-layer medium is used to simulate the real geological characteristics of the target asteroid, including a surface medium and a sub-surface medium; a second simulation module, for converting the first radar scattering cross-section parameter into a second radar scattering cross-section parameter corresponding to the minimum resolution unit of the standard sphere model under a double-layer medium, wherein the double-layer medium is used to simulate the real geological characteristics of the target asteroid, including a surface medium and a sub-surface medium; and a second simulation module, for converting the first radar scattering cross-section parameter into a second radar scattering cross-section parameter corresponding to the minimum resolution unit of the standard sphere model under a double-layer medium. The simulation module is used to use the minimum resolution unit as the verification area, and simulate the third radar cross-section parameters corresponding to the asteroid detection radar in the verification area according to the preset detection altitude and detection parameters, wherein the verification area is equivalent to the standard plane; the calculation module is used to calculate the first echo signal-to-noise ratio that meets the depth detection performance of the asteroid detection radar according to the second radar cross-section parameters and the third radar cross-section parameters; the flying module is used to use the drone to fly the asteroid detection radar, based on the same detection altitude and detection parameters, to obtain the ground echo data of the verification area under different radar detection modes, and calculate the second echo signal-to-noise ratio of the actual detection according to the ground echo data; the verification module is used to verify the depth detection performance of the asteroid detection radar according to the first echo signal-to-noise ratio and the second echo signal-to-noise ratio.

[0018] Another aspect of the present invention provides an electronic device, comprising: one or more processors; and a memory for storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the above method.

[0019] Another aspect of the present invention provides a computer-readable storage medium storing computer-executable instructions, which are used to implement the above method when executed.

[0020] Another aspect of the present invention provides a computer program product, the computer program product comprising computer executable instructions, and the instructions are used to implement the above method when being executed.

[0021] Compared with the prior art, the ground verification method and device for the depth detection performance of asteroid detection radar provided by the present invention have at least the following beneficial effects:

[0022] The ground verification method and device for the deep detection performance of the asteroid detection radar provided by the present invention first obtains the first echo signal-to-noise ratio (simulated signal-to-noise ratio) that meets the deep detection performance of the asteroid detection radar through a simulation model, and then obtains the second echo signal-to-noise ratio (actual signal-to-noise ratio) of the actual detection by flying the asteroid detection radar on a drone, and then compares and analyzes the difference between the simulated signal-to-noise ratio and the actual signal-to-noise ratio to verify and evaluate the deep detection capability of the asteroid detection radar. The ground verification method and device can be successfully applied to the scientific verification test and scientific feasibility assessment of the asteroid detection radar, which is beneficial to support the payload development and application work of the Tianwen-2 exploration mission. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The above and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

[0024] Figure 1 A flowchart schematically shows a method for ground verification of the depth detection performance of an asteroid detection radar according to an embodiment of the present invention;

[0025] Figure 2 The electromagnetic simulation model and the simulation result diagram of the radar cross section in the low frequency mode according to the embodiment of the present invention are schematically shown;

[0026] Figure 3 The electromagnetic simulation model and the simulation result diagram of the radar cross section in the high frequency mode according to the embodiment of the present invention are schematically shown;

[0027] Figure 4 A schematic diagram of a structure of a drone flight system according to an embodiment of the present invention is shown;

[0028] Figure 5 A schematic diagram of a ground echo diagram of an asteroid detection radar in a low-frequency channel according to an embodiment of the present invention is shown;

[0029] Figure 6 A schematic diagram of a ground echo graph in a high-frequency channel of an asteroid detection radar according to an embodiment of the present invention is shown;

[0030] Figure 7 A block diagram schematically shows a structure of a ground verification device for the depth detection performance of an asteroid detection radar according to an embodiment of the present invention;

[0031] Figure 8 The structure block diagram of an electronic device suitable for implementing a ground verification method of the depth detection performance of an asteroid detection radar according to an embodiment of the present invention is schematically shown. DETAILED DESCRIPTION

[0032] Below, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present invention. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of embodiments of the present invention. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of concepts of the present invention.

[0033] The terms used herein are only for describing specific embodiments and are not intended to limit the present invention. The terms "comprise", "include", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0034] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0035] When using expressions such as "at least one of A, B, and C, etc.", they should generally be interpreted according to the meaning of the expression commonly understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0036] In the embodiments of the present invention, the collection, updating, analysis, processing, use, transmission, provision, disclosure, storage and other aspects of the data involved (for example, including but not limited to user personal information) are in compliance with the provisions of relevant laws and regulations, are used for legitimate purposes, and do not violate public order and good morals. In particular, necessary measures are taken for user personal information to prevent illegal access to user personal information data and maintain the security of user personal information and network security.

[0037] The asteroid sounding radar is one of the important payloads of the Tianwen-2 exploration mission. It is used to obtain surface and subsurface radar echo data of the near-Earth asteroid 2016HO3 (Kamo'oalewa, Oscillating Star) and the main-belt comet 311P / (2013 P5) PANSTARRS (Panoramic Survey Telescope And Rapid Response System, Pan-STARRS), conduct sub-surface structure detection of asteroids and comets, and provide scientific detection data for cutting-edge scientific research on the origin and evolution of small celestial bodies.

[0038] When the asteroid detection radar flies around an asteroid or comet, it hovers at an appropriate time and transmits electromagnetic wave signals to the underground of the detection body. The electromagnetic wave signals propagate in the underground medium and produce reflection and scattering of electromagnetic waves when encountering targets such as soil stratification, ice layer, and rock. The radar signal is reflected by the surface of the asteroid to form a surface echo. The radar signal undergoes surface transmission, surface attenuation, and subsurface reflection to form a subsurface echo. The subsurface echo has an additional delay compared to the surface echo. The complete echo data of the orbiting detection is received by the rotation of the asteroid. By processing the radar echo, the depth information of the target with discontinuous underground electromagnetic parameters can be obtained, and scientific goals such as the detection of the internal structure of asteroids / comets and the inversion of dielectric constants can be completed.

[0039] The ultimate performance indicators of the asteroid detection radar will be reflected in two aspects: detection depth and resolution. In order to verify whether the asteroid detection radar can meet the index requirements in engineering missions, it is necessary to evaluate the depth detection capability of the asteroid detection radar through ground tests. Since the asteroid detection radar is my country's first small celestial body orbiting and penetrating detection radar, it is impossible to directly obtain the detection depth by detecting underground targets. It adopts a unique hovering orbit and relies on the rotation of the small celestial body for detection. However, there is currently a lack of mature ground detection depth verification methods available.

[0040] Based on this, an embodiment of the present invention provides a ground verification method and device for the deep detection performance of an asteroid detection radar, which is used to solve the technical problem that the actual detection performance of the radar cannot be accurately evaluated due to the lack of a verification method for the deep detection performance of an asteroid detection radar in the prior art.

[0041] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

[0042] Figure 1 A flow chart of a ground verification method for the deep detection performance of an asteroid detection radar according to an embodiment of the present invention is schematically shown.

[0043] like Figure 1As shown, the ground verification method for the deep detection performance of the asteroid detection radar of this embodiment may include operations S1 to S7, for example.

[0044] In operation S1, a standard sphere model is generated according to the property information of the target asteroid, wherein the standard sphere model is used to simulate the radar echo characteristics of the target asteroid.

[0045] In operation S2, based on the standard sphere model, according to the distance resolution unit size and azimuth resolution of different radar detection modes, a first radar cross section parameter corresponding to the minimum resolution unit of the standard sphere model under the metal material is obtained by simulation.

[0046] In operation S3, the first radar cross section parameter is converted into a second radar cross section parameter corresponding to the minimum resolution unit of the standard sphere model under the double-layer medium, wherein the double-layer medium is used to simulate the real geological characteristics of the target asteroid, including the surface medium and the sub-surface medium.

[0047] In operation S4, the minimum resolution unit is used as the verification area, and the third radar cross-section parameters corresponding to the asteroid detection radar in the verification area are obtained by simulation according to the preset detection height and detection parameters, wherein the verification area is equivalent to a standard plane.

[0048] In operation S5, a first echo signal-to-noise ratio that satisfies the depth detection performance of the asteroid detection radar is calculated based on the second radar cross-section parameter and the third radar cross-section parameter.

[0049] In operation S6, the asteroid detection radar is flown by the drone to obtain ground echo data of the verification area under different radar detection modes based on the same detection altitude and detection parameters, and the second echo signal-to-noise ratio of the actual detection is calculated based on the ground echo data.

[0050] In operation S7, the depth detection performance of the asteroid detection radar is verified based on the first echo signal-to-noise ratio and the second echo signal-to-noise ratio.

[0051] The depth detection capability of an asteroid detection radar can be equivalent to the signal-to-noise ratio of the asteroid subsurface echo received by the radar reaching the signal-to-noise ratio detection threshold. According to the radar equation, the radar transmission power required to penetrate the index depth can be expressed as:

[0052]

[0053] Among them, P t Indicates the radar transmission power;

[0054] SNR thr Indicates the receiver signal-to-noise ratio detection threshold;

[0055] α represents the attenuation factor of the medium;

[0056] R in It represents the one-way propagation distance in the medium;

[0057] R represents the distance between the target and the antenna;

[0058] σ represents the target radar cross section (RCS, Radar Cross Section);

[0059] B represents the system bandwidth;

[0060] λ represents wavelength;

[0061] G t , G r They represent the transmitting antenna gain and the receiving antenna gain respectively;

[0062] G p represents processing gain;

[0063] T represents the noise temperature;

[0064] F n represents the receiver noise figure;

[0065] L represents the receiver insertion loss;

[0066] K represents the Boltzmann constant.

[0067] For a given asteroid detection radar system, the transmit power, antenna gain, receiver noise figure (sensitivity), receiver insertion loss, and receiver signal-to-noise ratio detection threshold can be calibrated in the laboratory; the medium attenuation factor, propagation distance in the medium, target antenna distance, system bandwidth, wavelength, noise temperature, and Boltzmann constant are specified by the system design parameters.

[0068] The target radar cross section (RCS) is the only parameter related to the detection object. Therefore, the verification of the asteroid radar's deep detection capability can be converted into the echo signal-to-noise ratio of the verification ground detection target. According to the difference between the asteroid target radar cross section (RCS) and the verification ground detection target radar cross section (RCS), it is equivalent to whether it meets the requirements of the designed detection depth index in the detection of small celestial bodies.

[0069] Based on the above concept, in this embodiment, firstly, a standard sphere model can be generated through characteristic analysis of the engineering target asteroid according to the property information of the target asteroid (such as prior knowledge of density, heterogeneity, layered structure, etc.).

[0070] Then, based on the standard sphere model, according to the distance resolution unit size and azimuth resolution of different radar detection modes, the first radar scattering cross-section parameter corresponding to the minimum resolution unit of the standard sphere model under metal material and the second radar scattering cross-section parameter corresponding to the minimum resolution unit under double-layer medium are simulated.

[0071] In this embodiment, different radar detection modes include, for example, a low frequency mode and a high frequency mode.

[0072] Since the minimum resolution unit of a radar is usually a "plane" area under the spatial resolution of the radar system (determined by the radar wavelength, bandwidth, antenna aperture, etc.), in order to evaluate whether the radar can detect the target, it is necessary to convert the actual scattering characteristics of the target (such as the scattering cross section of a sphere) into the "plane" scattering cross section corresponding to the radar's minimum resolution unit.

[0073] In this embodiment, the second radar cross-section parameter is the radar cross-section parameter of the minimum resolution unit under the "standard sphere model", so it is also necessary to convert it into a radar cross-section parameter under the "standard plane model", that is, the third radar cross-section parameter.

[0074] After obtaining the third radar cross-section parameter, the echo signal-to-noise ratio that meets the depth detection performance of the asteroid detection radar is calculated according to the radar equation, that is, the first echo signal-to-noise ratio.

[0075] The first echo signal-to-noise ratio is used as the simulated signal-to-noise ratio of this verification method, and then the actual signal-to-noise ratio, that is, the second signal-to-noise ratio, needs to be obtained. In this embodiment, the actual signal-to-noise ratio is obtained by using a drone flying solution.

[0076] For example, a landing gear can be installed under the drone to provide installation space for the detection radar electronics box, antenna, etc. The landing gear can be made of non-metallic material to minimize the impact on the radar antenna. An equipment compartment is installed on the landing gear to place the detection radar electronics box and collector. The landing gear is connected to a reflective net to block the impact of the drone on the antenna, and the high-frequency antenna and low-frequency antenna are fixed on the reflective net. In terms of power supply, for example, it can be powered by a battery, which provides the power required for the radar electronics box and collector after voltage conversion. In terms of communication links, for example, uplink and downlink communication links can be designed to ensure real-time transmission and reception of remote control and telemetry for the detection radar.

[0077] In this embodiment, an asteroid detection radar is flown on a drone to obtain ground echo data of the verification area under different radar detection modes, and then the second echo signal-to-noise ratio of the actual detection can be calculated based on the ground echo data.

[0078] Finally, the first echo signal-to-noise ratio that meets the asteroid detection radar's deep detection performance is compared with the second echo signal-to-noise ratio obtained by actual detection to verify whether the asteroid detection radar's deep detection performance meets the standard.

[0079] The ground verification method for the deep detection performance of an asteroid detection radar provided in an embodiment of the present invention first obtains the first echo signal-to-noise ratio (simulated signal-to-noise ratio) that meets the deep detection performance of the asteroid detection radar through a simulation model, and then obtains the second echo signal-to-noise ratio (actual signal-to-noise ratio) of actual detection by flying the asteroid detection radar on a drone, and then compares and analyzes the difference between the simulated signal-to-noise ratio and the actual signal-to-noise ratio to verify and evaluate the deep detection capability of the asteroid detection radar. This ground verification method can be successfully applied to the scientific verification test and scientific feasibility assessment of the asteroid detection radar, which is beneficial to support the payload development and application work of the Tianwen-2 exploration mission.

[0080] According to an embodiment of the present invention, operation S2 is based on a standard sphere model, and according to the distance resolution unit size and azimuth resolution of different radar detection modes, simulating and obtaining a first radar cross-section parameter corresponding to the minimum resolution unit of the standard sphere model under a metal material includes:

[0081] According to the distance resolution unit size and azimuth resolution of different radar detection modes, the corresponding minimum resolution unit is selected on the standard sphere model;

[0082] An electromagnetic simulation model is established based on the minimum resolution unit, and the material of the standard sphere model is set as metal material;

[0083] The finite-difference time-domain method is used to simulate and obtain the first radar cross-section parameters corresponding to the minimum resolution unit of the standard sphere model under metal material.

[0084] In this embodiment, an electromagnetic simulation model can be established according to the distance resolution unit size and azimuth resolution corresponding to the low-frequency mode and the high-frequency mode, respectively, to obtain radar cross-section parameters, such as Figure 2 and Figure 3 shown.

[0085] Figure 2 The electromagnetic simulation model and the simulation result diagram of the radar scattering cross section in the low-frequency mode according to the embodiment of the present invention are schematically shown.

[0086] like Figure 2 As shown, (a) is the electromagnetic simulation model in low-frequency mode, the model size is: 5.4801 meters in the X direction, 28.1079 meters in the Y direction, 4.4950 meters in the Z direction, and the model material is metal. (b) is the simulation calculation result of the backscattering radar cross section in low-frequency mode, and the low-frequency radar cross section parameter of the metal model is 34dBsm.

[0087] Figure 3 The electromagnetic simulation model and the simulation result diagram of the radar scattering cross section in the high frequency mode according to the embodiment of the present invention are schematically shown.

[0088] like Figure 3 As shown, (a) is the electromagnetic simulation model in high-frequency mode, the model size is: 2.5221 meters in the X direction, 5.4044 meters in the Y direction, 0.1702 meters in the Z direction, and the model material is metal. (b) is the simulation calculation result of the backscattering radar cross section in high-frequency mode, and the low-frequency radar cross-section parameter of the metal model is 34dBsm.

[0089] According to an embodiment of the present invention, operation S3 of converting the first radar cross section parameter into a second radar cross section parameter corresponding to the minimum resolution unit of the standard sphere model in the double-layer medium includes:

[0090] Obtain the two-way transmittance-reflectivity product parameters of the target asteroid under the real geological characteristics;

[0091] Based on the first radar cross section parameter and the two-way transmittance-reflectivity product parameter, the second radar cross section parameter corresponding to the minimum resolution unit of the standard sphere model in the double-layer medium is calculated.

[0092] In this embodiment, after obtaining the first radar cross-section parameters of the metal material, it is further necessary to obtain the second radar cross-section parameters under the double-layer medium, that is, to simulate the real geological characteristics of the target asteroid, fill the double-layer medium structure for the standard sphere, and solve the second radar cross-section parameters.

[0093] The second radar cross section parameters under double-layer media can be calculated based on the two-way transmittance-reflectivity product parameters of the target asteroid under the actual geological characteristics. Specifically:

[0094] The second radar cross section parameter = the first radar cross section parameter × the two-way transmittance reflectivity product parameter.

[0095] The two-pass transmittance-reflectance product parameter is calculated as:

[0096] |T 01 ⋅T 10 | 2 |Γ 12 | 2

[0097] Among them, T 01 Indicates the transmittance of vacuum into the surface medium, T 10 represents the transmittance of the surface medium projected into the vacuum, Γ 12 Represents the reflectivity of the surface medium and the subsurface medium.

[0098] Specific:

[0099]

[0100]

[0101] Among them, ε r1 With ε r2 Represent the relative dielectric constants of the surface and subsurface media respectively.

[0102] In this embodiment, for the asteroid, the relative dielectric constant of the subsurface layer is 9, and the relative dielectric constant of the surface layer is 4, corresponding to a two-way transmittance reflectivity product of -15 dB.

[0103] In this embodiment, in the low-frequency mode: the low-frequency radar cross-section parameter of the metal model is multiplied by the product of the asteroid's two-way transmittance and reflectivity -15dB, and the radar cross-section parameter corresponding to the minimum resolution unit under the asteroid's double-layer medium is obtained as 19dBsm.

[0104] In this embodiment, in high-frequency mode: the high-frequency radar cross-section parameter of the metal model is multiplied by the product of the asteroid's two-way transmittance and reflectivity -15dB, and the radar cross-section parameter corresponding to the minimum resolution unit under the asteroid's double-layer medium is obtained as 19dBsm.

[0105] According to an embodiment of the present invention, operation S4 uses the minimum resolution unit as the verification area, and according to the preset detection height and detection parameters, the simulation obtains the third radar cross-section parameter corresponding to the asteroid detection radar in the verification area, including:

[0106] According to the ground characteristic information of the minimum resolution unit, a standard plane model of the minimum resolution unit is established;

[0107] According to the preset detection altitude and detection parameters, the third radar cross-section parameters of the asteroid detection radar in the standard plane model are obtained through simulation.

[0108] In this embodiment, the minimum resolution unit is used as the verification area, and based on the second radar cross section parameters under the "standard sphere model", the third radar cross section parameters under the "standard plane model" are further obtained.

[0109] For example, through the analysis of ground target characteristics, the minimum resolution unit is equivalent to a standard plane. According to the distance resolution unit size and azimuth resolution of different working modes, the material is set to be consistent with the actual ground, an electromagnetic simulation model is established, and the third radar scattering cross-section parameters under the "standard plane model" are obtained through simulation using the finite difference time domain method.

[0110] According to an embodiment of the present invention, operation S5 calculates a first echo signal-to-noise ratio that satisfies the depth detection performance of the asteroid detection radar according to the second radar cross-section parameter and the third radar cross-section parameter. For example, the signal-to-noise ratio can be calculated according to a radar equation. Specifically:

[0111] According to the application scenario and detection requirements of the detection radar for the target asteroid, calculated according to the radar equation, according to the asteroid dielectric constant (for example, 9) and loss tangent (for example, 0.01) in the mission book, the dielectric loss of the low-frequency channel penetrating 50m is 40.9 dB, the dielectric loss of the high-frequency channel penetrating 5m is 24.6 dB, the reflectivity difference is 2.5 dB, and the minimum detectable power of the radar is 8 dB. From this, it can be inferred that the surface echo signal-to-noise ratio must be greater than the dielectric loss + reflectivity difference + minimum detectable power of the radar. The total requirement is:

[0112] The signal-to-noise ratio of the low-frequency channel penetrating 50m surface echo is greater than 51 dB;

[0113] The high-frequency channel penetrates 5m surface echo signal-to-noise ratio greater than 35 dB;

[0114] Since the detection setting can use multi-frame accumulation to obtain the signal-to-noise ratio gain, the corresponding single-frame echo signal-to-noise ratio can be expressed as:

[0115] The signal-to-noise ratio of a single-frame echo from the asteroid surface in the low-frequency channel is greater than 21 dB;

[0116] The signal-to-noise ratio of a single-frame echo from the asteroid surface in the high-frequency channel is greater than 28 dB.

[0117] According to an embodiment of the present invention, operation S6 uses a drone to fly an asteroid detection radar, and based on the same detection altitude and detection parameters, obtains ground echo data of the verification area under different radar detection modes, including:

[0118] Configure the drone flight system;

[0119] Based on the configured UAV flight system, the UAV is controlled to reach the verification area to collect ground echo data under different radar detection modes according to the detection altitude and detection parameters.

[0120] In this embodiment, the drone flight system is as follows: Figure 4 shown.

[0121] Figure 4 The structure of the UAV flight system according to an embodiment of the present invention is schematically shown.

[0122] like Figure 4 As shown, the UAV flight system includes onboard equipment and ground station equipment.

[0123] Among them, the onboard equipment includes: radar electronics box, collector, UAV flight control and navigation system and the first UAV data transmission system (onboard radio).

[0124] The radar electronics box is used to generate and receive radar signals.

[0125] The collector is used to collect, process and package the data output by the radar electronics box.

[0126] The UAV flight control and navigation system is used to control the attitude, navigation and flight trajectory planning of the UAV, wherein the UAV flight control and navigation system is configured with a broadcast function, which can broadcast the flight status of the UAV in real time.

[0127] The first UAV data transmission system (onboard radio) is used to receive remote control and telemetry commands from the ground, and to transmit data output by the radar electronics box.

[0128] The ground station equipment includes: remote control and telemetry module, second UAV data transmission system (ground radio station) and control and processing computer.

[0129] The remote control and telemetry module is used to send and receive remote control and telemetry instructions in real time.

[0130] The second UAV data transmission system (ground radio station) is used to perform two-way communication with the first UAV data transmission system through the remote control and telemetry module to send remote control and telemetry commands or receive echo data.

[0131] The control and processing computer is used to perform data analysis on the echo data.

[0132] In this embodiment, a drone is used to detect a selected verification area, such as a volcanic landform detection area. The drone flies at an altitude of 600m to obtain detection data in low-frequency mode and high-frequency mode, and calculate the echo signal-to-noise ratio of different modes, such as Figure 5 and Figure 6 shown.

[0133] Figure 5 The figure schematically shows the ground echo diagram in the low-frequency channel of the asteroid detection radar according to an embodiment of the present invention.

[0134] like Figure 5 As shown in the figure, according to the actual detection settings, the flight altitude is 600m, the volcano surface scattering coefficient is 5dB, and the low-frequency channel volcano surface radar scattering cross section parameter is calculated to be 33dBsm. The volcano surface radar scattering cross section parameter is 14dB larger than the celestial body surface radar scattering cross section parameter.

[0135] Figure 6 The figure schematically shows the ground echo diagram in the high-frequency channel of the asteroid detection radar according to an embodiment of the present invention.

[0136] like Figure 6 As shown in the figure, according to the actual detection settings, the flight altitude is 600m, the volcano surface scattering coefficient is 5dB, and the high-frequency channel volcano surface radar scattering cross section parameter is calculated to be 25dBsm. The volcano surface radar scattering cross section parameter is 6dB greater than the celestial body surface radar scattering cross section parameter.

[0137] In this embodiment, the measured data of the depth detection index of the asteroid detection radar (second echo signal-to-noise ratio) is shown in Table 1.

[0138] Table 1 Asteroid detection radar depth index measured

[0139]

[0140] In this embodiment, the theoretical required data (first echo signal-to-noise ratio) for the deep detection performance of the asteroid detection radar is shown in Table 2.

[0141] Table 2 Theoretical data required to meet the deep detection performance of asteroid detection radar

[0142]

[0143] According to an embodiment of the present invention, operation S7 verifies the depth detection performance of the asteroid detection radar according to the first echo signal-to-noise ratio and the second echo signal-to-noise ratio, including:

[0144] In response to the second echo signal-to-noise ratio being greater than or equal to the first echo signal-to-noise ratio, it is characterized that the depth detection performance of the asteroid detection radar meets the requirements;

[0145] In response to the second echo signal-to-noise ratio being less than the first echo signal-to-noise ratio, it is characterized that the depth detection performance of the asteroid detection radar does not meet the requirements.

[0146] In this embodiment, if the second echo signal-to-noise ratio is greater than or equal to the first echo signal-to-noise ratio, it means that the depth detection performance of the asteroid detection radar meets the requirements; if the second echo signal-to-noise ratio is less than the first echo signal-to-noise ratio, it means that the depth detection performance of the asteroid detection radar does not meet the requirements.

[0147] Combining the measured data of the asteroid detection radar's depth detection indicators in Table 1 (second echo signal-to-noise ratio) with the theoretical required data for the asteroid detection radar's depth detection performance in Table 2 (first echo signal-to-noise ratio), it can be seen that the asteroid detection radar meets the depth detection requirements of 50m penetration for the low-frequency channel and 5m penetration for the high-frequency channel.

[0148] Figure 7 The structure of the ground verification device for the depth detection performance of an asteroid detection radar according to an embodiment of the present invention is schematically shown.

[0149] like Figure 7 As shown, the ground verification device 700 of the deep detection performance of the asteroid detection radar according to an embodiment of the present invention includes: a generation module 710, a first simulation module 720, a conversion module 730, a second simulation module 740, a calculation module 750, a flying module 760 and a verification module 770.

[0150] The generation module 710 is used to generate a standard sphere model according to the attribute information of the target asteroid, wherein the standard sphere model is used to simulate the radar echo characteristics of the target asteroid.

[0151] The first simulation module 720 is used to simulate and obtain the first radar cross-section parameter corresponding to the minimum resolution unit of the standard sphere model under metal material based on the standard sphere model according to the distance resolution unit size and azimuth resolution of different radar detection modes.

[0152] The conversion module 730 is used to convert the first radar cross-section parameter into a second radar cross-section parameter corresponding to the minimum resolution unit of the standard sphere model under the double-layer medium, wherein the double-layer medium is used to simulate the real geological characteristics of the target asteroid, including the surface medium and the sub-surface medium.

[0153] The second simulation module 740 is used to use the minimum resolution unit as the verification area, and simulate and obtain the third radar scattering cross-section parameters corresponding to the asteroid detection radar in the verification area according to the preset detection height and detection parameters, wherein the verification area is equivalent to the standard plane.

[0154] The calculation module 750 is used to calculate the first echo signal-to-noise ratio that meets the depth detection performance of the asteroid detection radar according to the second radar scattering cross-section parameter and the third radar scattering cross-section parameter.

[0155] The flight module 760 is used to use the drone to fly the asteroid detection radar, obtain the ground echo data of the verification area under different radar detection modes based on the same detection altitude and detection parameters, and calculate the second echo signal-to-noise ratio of the actual detection based on the ground echo data.

[0156] The verification module 770 is used to verify the depth detection performance of the asteroid detection radar according to the first echo signal-to-noise ratio and the second echo signal-to-noise ratio.

[0157] According to the embodiments of the present invention, any one or more of the modules, submodules, units, and subunits, or at least part of the functions of any one of them can be implemented in one module. According to the embodiments of the present invention, any one or more of the modules, submodules, units, and subunits can be split into multiple modules for implementation. According to the embodiments of the present invention, any one or more of the modules, submodules, units, and subunits can be at least partially implemented as hardware circuits, such as field programmable gate arrays (FPGAs), programmable logic arrays (PLAs), systems on chips, systems on substrates, systems on packages, application specific integrated circuits (ASICs), or can be implemented by hardware or firmware in any other reasonable way of integrating or packaging the circuit, or by any one of the three implementation methods of software, hardware, and firmware, or by a proper combination of any of them. Alternatively, according to the embodiments of the present invention, one or more of the modules, submodules, units, and subunits can be at least partially implemented as computer program modules, and when the computer program modules are run, the corresponding functions can be executed.

[0158] For example, any multiple of the generation module 710, the first simulation module 720, the conversion module 730, the second simulation module 740, the calculation module 750, the flight module 760, and the verification module 770 can be combined in one module / unit / subunit for implementation, or any one of the modules / units / subunits can be split into multiple modules / units / subunits. Alternatively, at least part of the functions of one or more of these modules / units / subunits can be combined with at least part of the functions of other modules / units / subunits and implemented in one module / unit / subunit. According to an embodiment of the present invention, at least one of the generation module 710, the first simulation module 720, the conversion module 730, the second simulation module 740, the calculation module 750, the hanging module 760 and the verification module 770 can be at least partially implemented as a hardware circuit, such as a field programmable gate array (FPGA), a programmable logic array (PLA), a system on a chip, a system on a substrate, a system on a package, an application-specific integrated circuit (ASIC), or can be implemented by hardware or firmware such as any other reasonable way of integrating or packaging the circuit, or implemented in any one of the three implementation methods of software, hardware and firmware or in any appropriate combination of any of them. Alternatively, at least one of the generation module 710, the first simulation module 720, the conversion module 730, the second simulation module 740, the calculation module 750, the hanging module 760 and the verification module 770 can be at least partially implemented as a computer program module, and when the computer program module is run, the corresponding function can be executed.

[0159] It should be noted that the ground verification device part of the depth detection performance of the asteroid detection radar in the embodiment of the present invention corresponds to the ground verification method part of the depth detection performance of the asteroid detection radar in the embodiment of the present invention. The description of the ground verification device part of the depth detection performance of the asteroid detection radar specifically refers to the ground verification method part of the depth detection performance of the asteroid detection radar, which will not be repeated here.

[0160] Figure 8 The structure block diagram of an electronic device suitable for implementing a ground verification method of the depth detection performance of an asteroid detection radar according to an embodiment of the present invention is schematically shown. Figure 8 The electronic device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0161] like Figure 8 As shown, the electronic device 800 according to an embodiment of the present invention includes a processor 801, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 802 or a program loaded from a storage part 808 to a random access memory (RAM) 803. The processor 801 may include, for example, a general-purpose microprocessor (e.g., a CPU), an instruction set processor and / or a related chipset and / or a special-purpose microprocessor (e.g., an application-specific integrated circuit (ASIC)), etc. The processor 801 may also include an onboard memory for caching purposes. The processor 801 may include a single processing unit or multiple processing units for performing different actions of the method flow according to an embodiment of the present invention.

[0162] In RAM 803, various programs and data required for the operation of electronic device 800 are stored. Processor 801, ROM 802 and RAM 803 are connected to each other via bus 804. Processor 801 performs various operations of the method flow according to the embodiment of the present invention by executing the programs in ROM 802 and / or RAM 803. It should be noted that the program can also be stored in one or more memories other than ROM 802 and RAM 803. Processor 801 can also perform various operations of the method flow according to the embodiment of the present invention by executing the programs stored in the one or more memories.

[0163] According to an embodiment of the present invention, the electronic device 800 may further include an input / output (I / O) interface 805, which is also connected to the bus 804. The electronic device 800 may further include one or more of the following components connected to the input / output (I / O) interface 805: an input portion 806 including a keyboard, a mouse, etc.; an output portion 807 including a cathode ray tube (CRT), a liquid crystal display (LCD), etc., and a speaker, etc.; a storage portion 808 including a hard disk, etc.; and a communication portion 809 including a network interface card such as a LAN card, a modem, etc. The communication portion 809 performs communication processing via a network such as the Internet. A drive 810 is also connected to the input / output (I / O) interface 805 as needed. A removable medium 811, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 810 as needed, so that the computer program read therefrom is installed into the storage portion 808 as needed.

[0164] According to an embodiment of the present invention, the method flow according to an embodiment of the present invention can be implemented as a computer software program. For example, an embodiment of the present invention includes a computer program product, which includes a computer program carried on a computer-readable storage medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from the network through the communication part 809, and / or installed from the removable medium 811. When the computer program is executed by the processor 801, the above-mentioned functions defined in the system of the embodiment of the present invention are executed. According to an embodiment of the present invention, the system, equipment, device, module, unit, etc. described above can be implemented by a computer program module.

[0165] The present invention also provides a computer-readable storage medium, which may be included in the device / apparatus / system described in the above embodiment; or may exist independently without being assembled into the device / apparatus / system. The above computer-readable storage medium carries one or more programs, and when the above one or more programs are executed, the method according to the embodiment of the present invention is implemented.

[0166] According to an embodiment of the present invention, the computer-readable storage medium may be a non-volatile computer-readable storage medium. For example, it may include but is not limited to: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the present invention, the computer-readable storage medium may be any tangible medium containing or storing a program, which may be used by or in combination with an instruction execution system, an apparatus or a device.

[0167] For example, according to an embodiment of the present invention, the computer-readable storage medium may include the ROM 802 and / or the RAM 803 described above and / or one or more memories other than the ROM 802 and the RAM 803 .

[0168] An embodiment of the present invention also includes a computer program product, which includes a computer program, and the computer program contains program code for executing the method provided by the embodiment of the present invention. When the computer program product runs on an electronic device, the program code is used to enable the electronic device to implement the method provided by the embodiment of the present invention.

[0169] When the computer program is executed by the processor 801, the above functions defined in the system / device of the embodiment of the present invention are executed. According to the embodiment of the present invention, the system, device, module, unit, etc. described above can be implemented by a computer program module.

[0170] In one embodiment, the computer program may rely on tangible storage media such as optical storage devices, magnetic storage devices, etc. In another embodiment, the computer program may also be transmitted and distributed in the form of signals on a network medium, and downloaded and installed through the communication part 809, and / or installed from a removable medium 811. The program code contained in the computer program may be transmitted using any appropriate network medium, including but not limited to: wireless, wired, etc., or any suitable combination of the above.

[0171] According to an embodiment of the present invention, the program code for executing the computer program provided by the embodiment of the present invention can be written in any combination of one or more programming languages. Specifically, these computing programs can be implemented using high-level process and / or object-oriented programming languages, and / or assembly / machine languages. Programming languages ​​include, but are not limited to, Java, C++, python, "C" language or similar programming languages. The program code can be executed entirely on the user computing device, partially on the user device, partially on the remote computing device, or entirely on the remote computing device or server. In the case of a remote computing device, the remote computing device can be connected to the user computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or can be connected to an external computing device (e.g., using an Internet service provider to connect through the Internet).

[0172] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present invention. In this regard, each box in the flowchart or block diagram may represent a module, a program segment, or a part of a code, and the above-mentioned module, program segment, or a part of the code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box may also occur in an order different from the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flowchart, and the combination of boxes in the block diagram or flowchart, can be implemented with a dedicated hardware-based system that performs the specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions. It can be understood by those skilled in the art that the features recorded in the various embodiments of the present invention can be combined and / or combined in various ways, even if such a combination or combination is not explicitly recorded in the present invention. In particular, without departing from the spirit and teachings of the present invention, the features recorded in the various embodiments of the present invention can be combined and / or combined in various ways. All these combinations and / or combinations fall within the scope of the present invention.

[0173] The embodiments of the present invention are described above. However, these embodiments are only for the purpose of illustration, and are not intended to limit the scope of the present invention. Although each embodiment is described above, it does not mean that the measures in each embodiment cannot be used in combination advantageously. Without departing from the scope of the present invention, those skilled in the art may make various substitutions and modifications, which should all fall within the scope of the present invention.

Claims

1. A ground verification method for the depth detection performance of an asteroid detection radar, characterized in that: The method comprises: Generate a standard sphere model according to the property information of the target asteroid, wherein the standard sphere model is used to simulate the radar echo characteristics of the target asteroid; Based on the standard sphere model, according to the distance resolution unit size and azimuth resolution of different radar detection modes, a first radar cross-section parameter corresponding to the minimum resolution unit of the standard sphere model under metal material is obtained by simulation; Converting the first radar cross section parameter into a second radar cross section parameter corresponding to the minimum resolution unit of the standard sphere model in a double-layer medium, wherein the double-layer medium is used to simulate the real geological characteristics of the target asteroid, including a surface medium and a sub-surface medium; Taking the minimum resolution unit as a verification area, simulating and obtaining the third radar cross-section parameter corresponding to the asteroid detection radar in the verification area according to the preset detection height and detection parameters, wherein the verification area is equivalent to a standard plane; calculating a first echo signal-to-noise ratio satisfying the depth detection performance of an asteroid detection radar according to the second radar cross section parameter and the third radar cross section parameter; Using a drone to fly the asteroid detection radar, based on the same detection altitude and detection parameters, obtain ground echo data of the verification area under different radar detection modes, and calculate the second echo signal-to-noise ratio of actual detection according to the ground echo data; The depth detection performance of the asteroid detection radar is verified based on the first echo signal-to-noise ratio and the second echo signal-to-noise ratio.

2. The method according to claim 1, characterized in that The simulation based on the standard sphere model and according to the distance resolution unit size and azimuth resolution of different radar detection modes to obtain the first radar cross-section parameter corresponding to the minimum resolution unit of the standard sphere model under the metal material includes: According to the distance resolution unit size and azimuth resolution of different radar detection modes, a corresponding minimum resolution unit is selected on the standard sphere model; Establishing an electromagnetic simulation model based on the minimum resolution unit, and setting the material of the standard sphere model to metal material; The first radar cross section parameter corresponding to the minimum resolution unit of the standard sphere model under the metal material is obtained by simulation using the finite difference time domain method.

3. The method according to claim 1, characterized in that The converting the first radar cross section parameter into a second radar cross section parameter corresponding to the minimum resolution unit of the standard sphere model in the double-layer medium comprises: Obtaining two-way transmittance-reflectivity product parameters of the target asteroid under real geological characteristics; Based on the first radar cross section parameter and the two-way transmittance-reflectivity product parameter, a second radar cross section parameter corresponding to the minimum resolution unit of the standard sphere model in the double-layer medium is calculated.

4. The method according to claim 3, characterized in that The two-way transmittance reflectance product parameter is calculated as: |T 01 ⋅T 10 | 2 |C 12 | 2 Among them, T 01 Indicates the transmittance of vacuum into the surface medium, T 10 represents the transmittance of the surface medium projected into the vacuum, Γ 12 Represents the reflectivity of the surface medium and the subsurface medium.

5. The method according to claim 1, characterized in that The step of using the minimum resolution unit as a verification area and simulating to obtain the third radar cross section parameter corresponding to the verification area of ​​the asteroid detection radar according to the preset detection height and detection parameters includes: Establishing a standard plane model of the minimum resolution unit according to the ground characteristic information of the minimum resolution unit; According to the preset detection altitude and detection parameters, the third radar cross-section parameters of the asteroid detection radar in the standard plane model are obtained by simulation.

6. The method according to claim 1, characterized in that The method of using the drone to fly the asteroid detection radar and obtaining ground echo data of the verification area under different radar detection modes based on the same detection altitude and detection parameters includes: Configure the drone flight system; Based on the configured UAV flight system, according to the detection altitude and the detection parameters, the UAV is controlled to reach the verification area to collect ground echo data under different radar detection modes.

7. The method according to claim 6, characterized in that The drone flight system includes: onboard equipment, wherein the onboard equipment includes: Radar electronics box, used to generate and receive radar signals; A collector, used for collecting, processing and packaging the data output by the radar electronics box; UAV flight control and navigation system, used to control the attitude, navigation and flight trajectory planning of the UAV, wherein the UAV flight control and navigation system is configured with a broadcast function, capable of broadcasting the flight status of the UAV in real time; The first UAV data transmission system is used to receive remote control and telemetry instructions from the ground, and to transmit the data output by the radar electronics box.

8. The method according to claim 7, characterized in that The UAV flight system further includes: a ground station device, wherein the ground station device includes: A remote control and telemetry module, used for sending and receiving the remote control and telemetry instructions in real time; A second UAV data transmission system is used to perform two-way communication with the first UAV data transmission system through the remote control and telemetry module to send the remote control and telemetry instructions or receive echo data; A control and processing computer is used for performing data analysis on the echo data.

9. The method according to claim 1, characterized in that: The verifying the depth detection performance of the asteroid detection radar according to the first echo signal-to-noise ratio and the second echo signal-to-noise ratio comprises: In response to the second echo signal-to-noise ratio being greater than or equal to the first echo signal-to-noise ratio, it is indicated that the depth detection performance of the asteroid detection radar meets the requirement; In response to the second echo signal-to-noise ratio being less than the first echo signal-to-noise ratio, it is characterized that the depth detection performance of the asteroid detection radar does not meet the requirements.

10. A ground verification device for the depth detection performance of an asteroid detection radar, characterized in that: The device comprises: A generation module, used to generate a standard sphere model according to the attribute information of the target asteroid, wherein the standard sphere model is used to simulate the radar echo characteristics of the target asteroid; A first simulation module is used to simulate and obtain a first radar cross-section parameter corresponding to the minimum resolution unit of the standard sphere model under metal material based on the standard sphere model and according to the distance resolution unit size and azimuth resolution of different radar detection modes; a conversion module, used to convert the first radar cross section parameter into a second radar cross section parameter corresponding to the minimum resolution unit of the standard sphere model under a double-layer medium, wherein the double-layer medium is used to simulate the real geological characteristics of the target asteroid, including a surface medium and a sub-surface medium; A second simulation module is used to use the minimum resolution unit as a verification area, and simulate and obtain a third radar cross-section parameter corresponding to the asteroid detection radar in the verification area according to a preset detection height and detection parameters, wherein the verification area is equivalent to a standard plane; a calculation module, configured to calculate a first echo signal-to-noise ratio that satisfies the depth detection performance of an asteroid detection radar according to the second radar cross-section parameter and the third radar cross-section parameter; A flying module is used to fly the asteroid detection radar by using a drone, obtain ground echo data of the verification area under different radar detection modes based on the same detection altitude and detection parameters, and calculate the second echo signal-to-noise ratio of the actual detection according to the ground echo data; A verification module is used to verify the depth detection performance of the asteroid detection radar according to the first echo signal-to-noise ratio and the second echo signal-to-noise ratio.

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