Method for determining refracted optical path and imaging method for multi-transmitter multi-receiver radar

Abstract

The present invention provides a method for determining the refracted optical path of a multi-transmitter, multi-receiver radar. The method includes: obtaining a radar imaging range matrix in a preset coordinate system based on the radar's detection profile, wherein the range matrix includes multiple scatterers; calculating, for each scatterer, the corresponding unilateral optical path information to obtain unilateral optical path information for multiple scatterers; and determining the refracted optical path based on the unilateral optical path information for the multiple scatterers; wherein the unilateral optical path information is the time delay information of the electromagnetic wave propagating from the antenna position to the scatterer; and the unilateral optical path information corresponding to the scatterer includes the unilateral optical path information for each antenna corresponding to the scatterer. The present invention also provides an imaging method.

Description

Technical Field

[0001] The present invention relates to the field of data processing, and more particularly to a method for determining a refracted light path and an imaging method for a multi-transmitter multi-receiver radar. Background Art

[0002] Multi-transmitter, multi-receiver array ground-penetrating radar uses multiple receiving and transmitting antennas to form an antenna array, generating multiple baselines for subsurface detection. Compared to traditional single-transmitter, single-receiver detection methods, array radar can acquire multiple baselines in a single survey, enabling the detection of relevant areas under limited conditions.

[0003] The Lunar Regolith Penetrating Radar (LRPR) is a typical array-type ground-penetrating radar (GPR). Carried on the Chang'e-5 lander, it marks the first application of an array-type GPR in the exploration of extraterrestrial objects. The LRPR, mounted on the underside of the Chang'e-5 lander, must remain stationary due to the lander's inherent inability to autonomously move on the lunar surface. Therefore, it utilizes a multi-transmitter, multi-receiver array of twelve ultra-wideband Vivaldi antennas. Antennas 1 through 10 are arranged in a straight line, with antenna 11 sharing the same horizontal plane (height) as the first ten, and antenna 12 located separately at a different height. The system can pair any two antennas for transmission and reception at the same time. By combining the transmit and receive antennas, a total of 132 baselines can be acquired, enabling the detection and imaging of the lunar subsurface structure beneath the antenna array.

[0004] During conventional single-transmitter, single-receiver ground-penetrating radar (GPR), the relative geometric relationship between the antennas remains constant, and radar coverage of an area is achieved by moving the radar itself. The fixed relative antenna positions ensure that the time delays of each channel in the radar image represent the same meaning. In other words, the same time delay in different channels corresponds to the same depth at different radar detection locations. Therefore, simply arranging the single-channel data into a radar image can provide intuitive information about the subsurface structure. Unlike conventional radar images, due to the multi-transmitter, multi-receiver, and uneven antenna distribution of the lunar soil structure detector, the geometric relationships between the transmitting and receiving antennas vary between the individual channels, making the relationship between the time delays of each channel and the location of subsurface scatterers uncertain. After radar detection, imaging processing is required to obtain a human-interpretable subsurface structure map. Summary of the Invention

[0005] In view of the above problems, the present invention provides a method for determining a refracted light path and an imaging method for a multi-transmitter multi-receiver radar.

[0006] According to a first aspect of the present invention, a method for determining the refracted light path of a multi-transmitter and multi-receiver radar is provided, comprising: obtaining a range matrix of radar imaging in a preset coordinate system based on the detection profile area of ​​the radar, wherein the range matrix includes multiple scatterers; for each scatterer, calculating the unilateral optical path information corresponding to the scatterer to obtain the unilateral optical path information of the multiple scatterers; and determining the refracted light path based on the unilateral optical path information of the multiple scatterers; wherein the unilateral optical path information is the time delay information of the electromagnetic wave propagating from the antenna position to the scatterer; and the unilateral optical path information corresponding to the scatterer includes the unilateral optical path information of each antenna corresponding to the scatterer.

[0007] According to an embodiment of the present invention, the preset coordinate system is obtained by: setting a vacuum and soil stratification model of the area detected by the radar; and establishing the preset coordinate system according to the detection area and antenna position based on the vacuum and soil stratification model.

[0008] According to an embodiment of the present invention, the method for determining the refracted optical path of the multi-transmitter multi-receiver radar further includes: calculating the single-side optical path information corresponding to the scatterer based on the principle of shortest optical path.

[0009] According to a second aspect of the present invention, there is provided an imaging method, comprising: obtaining a refracted optical path, the refracted optical path comprising a set of optical path information, the optical path information comprising single-sided optical path information corresponding to each antenna; determining propagation delay information of a plurality of electromagnetic waves based on the set of optical path information; obtaining a plurality of aligned scatterer signals based on the propagation delay information of the plurality of electromagnetic waves; and generating a target image based on the plurality of aligned scatterer signals using a cross-correlation method; wherein the refracted optical path is obtained using the method provided by the present invention.

[0010] According to an embodiment of the present invention, obtaining the aligned multiple scatterer signals based on the propagation delay information of the multiple electromagnetic waves includes: performing compensation alignment processing based on the total time delay to obtain the aligned multiple scatterer signals.

[0011] According to an embodiment of the present invention, generating a target image based on the aligned multiple scatterer signals by using a cross-correlation method includes: obtaining brightness information of each scatterer in a range matrix based on the aligned multiple scatterer signals by using a cross-correlation method; and generating a target image based on the brightness information.

[0012] The third aspect of the present invention provides a refracted optical path determination device for a multi-transmitter and multi-receiver radar, comprising: a first acquisition module, used to obtain a range matrix of radar imaging in a preset coordinate system based on the detection profile area of ​​the radar, wherein the range matrix includes multiple scatterers; a second acquisition module, used to calculate the unilateral optical path information corresponding to each scatterer, and obtain the unilateral optical path information of multiple scatterers; and a first determination module, used to determine the refracted optical path based on the unilateral optical path information of the multiple scatterers; wherein the unilateral optical path information is the time delay information of the electromagnetic wave propagating from the antenna position to the scatterer; the unilateral optical path information corresponding to the scatterer includes the unilateral optical path information of each antenna corresponding to the scatterer.

[0013] The fourth aspect of the present invention provides an imaging device, comprising: a first acquisition module for acquiring a refracted optical path, wherein the refracted optical path includes a set of optical path information, wherein the optical path information includes single-sided optical path information corresponding to each antenna; a second determination module for determining propagation delay information of multiple electromagnetic waves based on the set of optical path information; an alignment processing module for obtaining aligned multiple scatterer signals based on the propagation delay information of the multiple electromagnetic waves; and an image generation module for generating a target image based on the aligned multiple scatterer signals using a cross-correlation method; wherein the refracted optical path is obtained using the device provided by the present invention.

[0014] The fifth aspect of the present invention provides an electronic device, comprising: one or more processors; 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 execute the above-disclosed method.

[0015] The sixth aspect of the present invention further provides a computer-readable storage medium having executable instructions stored thereon, which, when executed by a processor, causes the processor to execute the method disclosed above. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above contents 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:

[0017] Figure 1 A flowchart of a method for determining a refracted light path of a multi-transmitter multi-receiver radar according to an embodiment of the present invention is schematically shown;

[0018] Figure 2 A schematic diagram schematically illustrates time delay information according to an embodiment of the present invention;

[0019] Figure 3 A flowchart of an imaging method according to an embodiment of the present invention is schematically shown;

[0020] Figure 4A A schematic diagram schematically illustrates raw data used in radar imaging according to an embodiment of the present invention;

[0021] Figure 4B A schematic diagram schematically illustrates a target image according to an embodiment of the present invention;

[0022] Figure 5 A block diagram schematically illustrates the structure of a device for determining a refracted optical path of a multi-transmitter multi-receiver radar according to an embodiment of the present invention;

[0023] Figure 6 Schematically shows a structural block diagram of an imaging device according to an embodiment of the present invention and

[0024] Figure 7 The block diagram of an electronic device suitable for implementing a method for determining a refracted light path and / or an imaging method for a multi-transmitter multi-receiver radar according to an embodiment of the present invention is schematically shown. DETAILED DESCRIPTION

[0025] Hereinafter, 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 the concept of the present invention.

[0026] 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 presence of the features, steps, operations and / or components, but do not exclude the presence or addition of one or more other features, steps, operations or components.

[0027] All terms used herein (including technical and scientific terms) 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.

[0028] When expressions such as "at least one of A, B and C, etc." are used, they should generally be interpreted in accordance with 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.).

[0029] pass Figure 1 A method for determining the refracted light path of a multi-transmitter multi-receiver radar in a disclosed embodiment is described in detail.

[0030] Figure 1 The flowchart of the method for determining the refracted light path of the multi-transmitter multi-receiver radar according to an embodiment of the present invention is schematically shown. Figure 1 As shown, this embodiment includes operations S101 to S103.

[0031] In operation S101 , a range matrix of radar imaging is obtained in a preset coordinate system according to a detection cross-section area of ​​the radar, where the range matrix includes a plurality of scatterers.

[0032] The preset coordinate system is obtained by: setting a vacuum and soil layering model of the area detected by the radar; and establishing a preset coordinate system according to the detection area and antenna position based on the vacuum and soil layering model.

[0033] In operation S102 , for each scatterer, single-side optical path information corresponding to the scatterer is calculated to obtain single-side optical path information of multiple scatterers.

[0034] The unilateral optical path information is the time delay information of the electromagnetic wave propagating from the antenna position to the scatterer; the unilateral optical path information corresponding to the scatterer includes the unilateral optical path information of each antenna corresponding to the scatterer.

[0035] The single-sided optical path information corresponding to the scatterer is calculated based on the principle of shortest optical path.

[0036] In operation S103 , a refracted light path is determined based on single-side optical path information of a plurality of scatterers.

[0037] It can be understood that the imaging process of an array ground-penetrating radar can be divided into two steps: calculating the optical path information of subsurface scatterers corresponding to each antenna, and aligning and cross-correlating the single-channel radar signals. Before aligning the single-channel radar signals, the optical path information of the scatterers corresponding to each antenna must be calculated. The method for determining the refracted optical path for a multi-transmitter, multi-receiver radar provided by the present invention can obtain the refracted optical path, including the single-side optical path information corresponding to each antenna.

[0038] For example, under the premise that the detection medium model and antenna position are known, the optical path corresponding to any three-dimensional subsurface scatterer is calculated.

[0039] Step 1: For example, a vacuum and soil layer model is set for the area detected by the radar. The layer model includes the dielectric constant information and position information of each layer. For example, a vacuum-soil layer model is set for the area detected by the lunar soil structure detector.

[0040] Step 2, for example, establish an imaging coordinate system based on the detection area and antenna position. For example, establish an imaging coordinate system based on the detection area, let the vacuum-lunar soil interface be z=0, where the area z<0 is vacuum and the area z>0 is lunar soil; the position of the first antenna of the lunar soil structure detector is Establish a coordinate system.

[0041] Step 3: Based on the radar's detection profile, a radar imaging range matrix is ​​constructed from the coordinate system. For example, the Chang'e-5 lunar soil structure detector has the highest antenna coverage in the range 0 ≤ x ≤ 1.56 m, y = 0. Considering its detection depth of 2.5 m, the imaging range is selected to be 0 ≤ x ≤ 1.56 m, 0 ≤ z ≤ 2.5 m, y = 0. If the antenna's coverage in the y direction is sufficiently large, the imaging matrix can be expanded accordingly in the y dimension.

[0042] Step 4: Select a point (x, y, z) in the imaging range matrix as an imaginary scatterer; for N (e.g., 12) antennas, calculate their unilateral optical path τ relative to the imaginary scatterer. n (x, y, z)…(1≤n≤N). This single-sided optical path refers to the time delay for an electromagnetic wave to propagate from the antenna position to the hypothetical scattering point. This can be calculated using an optimization method based on the principle of shortest optical path. It should also be noted that, based on the principle of reversibility of optical paths, the single-sided optical path also refers to the optical path required for the scattered echo from the hypothetical scattering point to propagate back to the corresponding antenna.

[0043] Step 5: Repeat steps 1-4 for all (x, y, z) points in the imaging range matrix to obtain all single-side optical path information.

[0044] Figure 2 Schematic diagram showing time delay information according to an embodiment of the present invention. Figure 2 , assuming that the refractive surface is at z = 0, the x-axis and y-axis jointly determine the position of the incident point, and the z-axis is the calculated electromagnetic wave propagation delay. Based on Fermat's principle, the scattering point should be at Figure 2 The displayed time delay surface is the extreme point, so the (x,y) pair where the minimum point on the surface is located represents the location of the actual incident point. In this example, the antenna is at (0, 0, -0.88) and the scattering point is at (1.3, 0, 0.9).

[0045] pass Figure 3 The imaging method of the disclosed embodiment is described in detail.

[0046] Figure 3 Schematically shows a flow chart of an imaging method according to an embodiment of the present invention. Figure 3 As shown, this embodiment includes operations S301 to S304.

[0047] In operation S301 , a refracted light path is acquired, where the refracted light path includes a set of optical path information, and the optical path information includes single-side optical path information corresponding to each antenna.

[0048] For example, the refracted light path is obtained by using the refracted light path determination method for the multi-transmitter multi-receiver radar provided by the present invention.

[0049] For example, through optical tracking methods, the principle of shortest optical path is used to calculate the refraction path of electromagnetic waves after they are radiated from the antenna and pass through the interface between the vacuum and the lunar soil.

[0050] In operation S302 , propagation delay information of a plurality of electromagnetic waves is determined based on a set of optical path information.

[0051] The single-sided optical path information includes the optical path information of the transmitting side and the optical path information of the receiving side; based on the set of optical path information, the propagation delay information of multiple electromagnetic waves is determined, including: for any electromagnetic wave, based on the optical path information of the transmitting side and the optical path information of the receiving side, calculating the total time delay of any electromagnetic wave; and using the total time delay as the propagation delay information of any electromagnetic wave.

[0052] This step can accurately calculate the propagation delay of electromagnetic waves.

[0053] In operation S303 , a plurality of aligned scatterer signals are obtained according to the propagation delay information of the plurality of electromagnetic waves.

[0054] Obtaining a plurality of aligned scatterer signals according to propagation delay information of a plurality of electromagnetic waves includes: performing compensation alignment processing according to a total time delay to obtain a plurality of aligned scatterer signals.

[0055] This step can align scatterer signals from arbitrary directional and depth positions.

[0056] In operation S304 , a target image is generated according to the aligned scatterer signals by using a cross-correlation method.

[0057] Generating a target image based on the aligned multiple scatterer signals using a cross-correlation method includes: obtaining brightness information of each scatterer in the range matrix based on the aligned multiple scatterer signals using a cross-correlation method; and generating a target image based on the brightness information.

[0058] The imaging method provided by the present invention can be applied to array-type ground penetrating radar to image radar detection data.

[0059] For example, three-dimensional array ground penetrating radar imaging based on cross-correlation.

[0060] Step 1: Select an imaginary scattering point (x, y, z) and start processing by selecting the i-th radar data. The transmitting antenna corresponding to the i-th radar data is denoted as antenna m, and the receiving antenna is denoted as antenna n.

[0061] Step 2: Combine the optical path lengths of the transmitting and receiving sides to obtain the total time delay τ i (x,y,z)=τ m (x,y,z)+τ n (x,y,z).

[0062] Step 3: Delay τ i (x, y, z) compensates the radar single-channel data and aligns the single-channel data.

[0063] Step 4: Count the total number of radar channels as J. For 1≤i≤J, repeat steps 1-3.

[0064] Step 5: Perform zero-delay cross-correlation on each of the J-channel aligned radar single-channel data. The sum of all cross-correlation results is recorded as the brightness I(x,y,z) at (x,y,z).

[0065] Step 6: Repeat steps 1-5 for all (x, y, z) points in the imaging range matrix to obtain the total brightness matrix.

[0066] Preferably, in order to reduce the impact of noise and interference signals on imaging quality, the length of the signal involved in the calculation of the zero-delay cross correlation in step 4 can be comparable to the pulse length of the pulse signal emitted by the radar.

[0067] As you can see, once the antenna positions and the detection area model are determined, high-precision imaging of the detection area can be achieved, with the resulting image matching the radar's designed resolution. Because it directly calculates electromagnetic wave propagation through ray tracing, it doesn't restrict antennas to being on the same plane, making it applicable to any antenna configuration and operating conditions.

[0068] In order to better understand the present invention, the content of the present invention is further described below in conjunction with the embodiments, but the present invention is not limited to the following embodiments.

[0069] Take a set of measured data from a lunar soil structure detector as an example, see Figure 4A , Figure 4A The figure schematically shows the raw data used in radar imaging according to an embodiment of the present invention.

[0070] Part 1: Calculate the optical path information of each antenna corresponding to the subsurface scatterer.

[0071] The first step is to establish the imaging coordinate system and calculate the time delay of the 12 antennas corresponding to each imaginary scattering point in the final imaging.

[0072] Step 1. Set the vacuum-lunar soil layering model of the area detected by the lunar soil structure detector. When calculating the optical path of the buried object in this embodiment, it is necessary to understand the boundary between the vacuum and the lunar soil and the dielectric constant of the lunar soil in order to accurately calculate the required optical path. In practice, it is usually assumed that the detection space is composed of a semi-infinite vacuum and a semi-infinite lunar soil layer, and the dielectric constant of the lunar soil can be measured by the lunar soil samples of the Apollo program or Chang'e 5, or estimated using radar data. The relative dielectric constant of the vacuum is 1, and the relative dielectric constant of the lunar soil is recorded here as ∈ r .

[0073] Step 2: Establish an imaging coordinate system based on the detection area. To make the generated target image easier to understand, the vacuum-lunar soil interface is typically taken as the z = 0 plane, with the direction of the lunar soil layer as the positive direction. The position of the Chang'e-5 lander's antenna No. 1 is taken as the zero point in the x and y directions. Chang'e-5 antennas No. 1 through No. 10 are collinear, with this as the x direction and the perpendicular direction as the y direction. In this case, the region z ≤ 0 represents the vacuum layer, and z ≥ 0 represents the lunar soil layer; the region x ≥ 0 represents the lunar soil structure detector antenna coverage area; and the region y = 0 represents the area with the densest antenna coverage. This established coordinate system matches the radar's detection target, making it easier to interpret.

[0074] Step 3: Select the radar imaging profile range from the coordinate system and establish the range matrix. The lunar soil structure detector cannot be moved, so its detection area is set within the antenna coverage area, that is, the 1.56-meter area between antennas 1 and 10. Based on ground verification tests, its detection depth is set to 2.5 meters. Therefore, the imaging area is 0 ≤ x ≤ 1.56 m, 0 ≤ z ≤ 2.5 m, and y = 0.

[0075] Step 4. Select a point (x, 0, z) in the imaging range matrix as an imaginary scatterer. For each of the 12 antennas, calculate the unilateral optical path relative to the imaginary scatterer. Select a point (x, 0, z) in the region. The vacuum-soil boundary is between it and the antenna. Electromagnetic waves will refract at this interface, so the refracted optical path needs to be calculated. The position of antenna m is (x ma ,y ma ,z ma ), the incident point of refraction is (x i ,y i ,0), the complete single-sided optical path is expressed as:

[0076]

[0077] Among them, only (x i ,y i ) is an unknown number. According to Fermat’s principle, the path of light propagation is the path where the optical path takes the extreme value, so by minimizing τma (x,z,x i ,y i ).

[0078]

[0079] Solve (x i ,y i ), recorded as (x′ i ,y′ i ), and then the corresponding single-sided optical path is obtained.

[0080]

[0081] Step 5: Repeat steps 1-4 for all (x, 0, z) points in the imaging range matrix to obtain all the required single-sided optical path information. Since imaging is presented as an image, the imaging range is a matrix obtained by sampling the area 0 ≤ x ≤ 1.56 m, 0 ≤ z ≤ 2.5 m, and y = 0. Simply repeat steps 1-4 for each pixel to obtain all the required single-sided optical path information.

[0082] Part 2: Cross-correlation imaging based on the obtained time delay.

[0083] Step 1: Select an imaginary scattering point (x, 0, z) and start processing by selecting the i-th radar data. The transmitting antenna corresponding to the i-th radar data is denoted as antenna m, and the receiving antenna is denoted as antenna n.

[0084] Step 2: Combine the optical paths on the transmitting and receiving sides to obtain the total time delay. Due to the principle of reversibility of optical paths, both the optical paths on the transmitting and receiving sides can be simplified into single-side optical paths. Here, the total time delay can be obtained by simply adding the two single-side optical paths.

[0085] τ i (x,0,z)=τ m (x,0,z)+τ n (x,0,z)

[0086] Step 3: Delay the corresponding radar single channel data by the total time τ i (x,0,z) is aligned. The radar single channel data is denoted as S i (t), where t = 0 represents the pulse signal just radiated from the transmitting antenna. The purpose of aligning the signal is to make t = 0 represent the pulse signal at the scattering point just arriving at the receiving antenna. The aligned signal is expressed as:

[0087] S′ i (t) = S i (t+τ i (x,0,0z))

[0088] Step 4: Repeat steps 1 to 3 for 1≤i≤132. At this time, all radar signals at t=0 are at the time when the scattered echo of the point (x, 0, z) reaches the receiving antenna.

[0089] Step 5: Perform zero-delay cross-correlation on each of the 132 aligned radar channel data. The sum of all cross-correlation results is recorded as the brightness I(x,0,z) at (x,0,z). The purpose of cross-correlation is to extract the echo energy information of the scattering point as a matched filter. Therefore, the time length of the cross-correlation will not be longer than the time width of the radar pulse signal, which is recorded as τ. p Take the i-th data and the j-th data for cross correlation, which can be expressed as:

[0090]

[0091] Superimposing all cross-correlation results can integrate the data of all observation baselines, enhance the signal-to-noise ratio and imaging resolution, and obtain the final brightness value:

[0092]

[0093] Step 6: Repeat steps 1-5 for all pixels in the imaging range matrix to obtain the total brightness matrix, which is the imaging matrix. Figure 4B , Figure 4B A schematic diagram of a target image according to an embodiment of the present invention is schematically shown.

[0094] Figure 5 The structure block diagram of the device for determining the refracted light path of the multi-transmitter multi-receiver radar according to an embodiment of the present invention is schematically shown.

[0095] like Figure 5 As shown, the refracted light path determination device 500 of the multi-transmitter multi-receiver radar of this embodiment includes a first obtaining module 510 , a second obtaining module 520 and a first determining module 530 .

[0096] The first acquisition module 510 is used to obtain the range matrix of the radar imaging in a preset coordinate system according to the detection profile area of ​​the radar, and the range matrix includes multiple scatterers; the second acquisition module 520 is used to calculate the unilateral optical path information corresponding to each scatterer, and obtain the unilateral optical path information of multiple scatterers; and the first determination module 530 is used to determine the refracted optical path according to the unilateral optical path information of the multiple scatterers; wherein the unilateral optical path information is the time delay information of the electromagnetic wave propagating from the antenna position to the scatterer; the unilateral optical path information corresponding to the scatterer includes the unilateral optical path information of each antenna corresponding to the scatterer.

[0097] According to an embodiment of the present invention, any multiple modules among the first obtaining module 510, the second obtaining module 520, and the first determining module 530 can be combined into one module for implementation, or any one of the modules can be split into multiple modules. Alternatively, at least part of the functions of one or more of these modules can be combined with at least part of the functions of other modules and implemented in one module. According to an embodiment of the present invention, at least one of the first obtaining module 510, the second obtaining module 520, and the first determining module 530 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 in any other reasonable manner of integrating or packaging the circuit, or can be 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 first obtaining module 510, the second obtaining module 520, and the first determining module 530 can be at least partially implemented as a computer program module, which can perform the corresponding function when the computer program module is executed.

[0098] Figure 6 The structure of the imaging device according to the embodiment of the present invention is schematically shown.

[0099] like Figure 6 As shown, the imaging device 600 of this embodiment includes a first acquisition module 610 , a second determination module 620 , an alignment processing module 630 and an image generation module 640 .

[0100] The first acquisition module 610 is used to obtain the refracted optical path, which includes a set of optical path information, and the optical path information includes single-side optical path information corresponding to each antenna; the second determination module 620 is used to determine the propagation delay information of multiple electromagnetic waves based on the set of optical path information; the alignment processing module 630 is used to obtain multiple aligned scatterer signals based on the propagation delay information of the multiple electromagnetic waves; and the image generation module 640 is used to generate a target image based on the multiple aligned scatterer signals using a cross-correlation method.

[0101] For example, the refracted light path is obtained by using the refracted light path determining device for the multi-transmitter multi-receiver radar provided by the present invention.

[0102] According to an embodiment of the present invention, any multiple modules among the first acquisition module 610, the second determination module 620, the alignment processing module 630, and the image generation module 640 can be combined into a single module, or any one of them can be split into multiple modules. Alternatively, at least part of the functionality of one or more of these modules can be combined with at least part of the functionality of other modules and implemented in a single module. According to an embodiment of the present invention, at least one of the first acquisition module 610, the second determination module 620, the alignment processing module 630, and the image generation module 640 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 in hardware or firmware by any other reasonable means of integrating or packaging circuits, or can be 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 first acquisition module 610 , the second determination module 620 , the alignment processing module 630 and the image generation module 640 may be at least partially implemented as a computer program module, which may perform corresponding functions when executed.

[0103] Figure 7 The block diagram of an electronic device suitable for implementing a method for determining a refracted light path and / or an imaging method for a multi-transmitter multi-receiver radar according to an embodiment of the present invention is schematically shown.

[0104] like Figure 7 As shown, the electronic device 700 according to an embodiment of the present invention includes a processor 701, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 702 or a program loaded from a storage portion 708 into a random access memory (RAM) 703. The processor 701 may, for example, include 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 701 may also include an onboard memory for caching purposes. The processor 701 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.

[0105] Various programs and data required for the operation of the electronic device 700 are stored in the RAM 703. The processor 701, ROM 702, and RAM 703 are connected to each other via a bus 704. The processor 701 performs various operations according to the method flow of the embodiment of the present invention by executing the programs in the ROM 702 and / or RAM 703. It should be noted that the programs may also be stored in one or more memories other than the ROM 702 and RAM 703. The processor 701 may also perform various operations according to the method flow of the embodiment of the present invention by executing the programs stored in the one or more memories.

[0106] According to an embodiment of the present invention, electronic device 700 may further include an input / output (I / O) interface 705, which is also connected to bus 704. Electronic device 700 may further include one or more of the following components connected to I / O interface 705: an input section 706 including a keyboard, a mouse, etc.; an output section 707 including devices such as a cathode ray tube (CRT), a liquid crystal display (LCD), and speakers; a storage section 708 including a hard disk; and a communication section 709 including a network interface card such as a LAN card or a modem. Communication section 709 performs communication processing via a network such as the Internet. A drive 710 is also connected to I / O interface 705 as needed. Removable media 711, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed in drive 710 as needed, so that computer programs read from the removable media can be installed into storage section 708 as needed.

[0107] The present invention also provides a computer-readable storage medium, which may be included in the device / apparatus / system described in the above embodiments, or may exist independently and not incorporated into the device / apparatus / system. The computer-readable storage medium carries one or more programs, which, when executed, implement the method according to the embodiments of the present invention.

[0108] According to an embodiment of the present invention, a computer-readable storage medium may be a non-volatile computer-readable storage medium, such as, but 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, a computer-readable storage medium may be any tangible medium that contains or stores a program that can be used by or in combination with an instruction execution system, apparatus, or device. For example, according to an embodiment of the present invention, a computer-readable storage medium may include the ROM 702 and / or RAM 703 described above and / or one or more memories other than ROM 702 and RAM 703.

[0109] Embodiments of the present invention also include a computer program product comprising a computer program containing program code for executing the method shown in the flowchart. When the computer program product is executed in a computer system, the program code causes the computer system to implement the refracted light path determination method and / or imaging method for a multi-transmitter multi-receiver radar provided in embodiments of the present invention.

[0110] The computer program executes the above functions defined in the system / device of the embodiment of the present invention when the computer program is executed by the processor 701. According to the embodiment of the present invention, the system, device, module, unit, etc. described above can be implemented by a computer program module.

[0111] In one embodiment, the computer program may be stored on a tangible storage medium such as an optical storage device or a magnetic storage device. In another embodiment, the computer program may be transmitted and distributed in the form of a signal on a network medium, downloaded and installed via the communication portion 709, and / or installed from a removable medium 711. The program code contained in the computer program may be transmitted using any appropriate network medium, including but not limited to wireless, wired, or any suitable combination thereof.

[0112] In such an embodiment, the computer program can be downloaded and installed from a network via the communication section 709 and / or installed from the removable medium 711. When the computer program is executed by the processor 701, the above-described functions defined in the system of the embodiment of the present invention are performed. According to the embodiment of the present invention, the systems, devices, means, modules, units, etc. described above can be implemented by computer program modules.

[0113] 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 procedural 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 a remote computing device, or entirely on a 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 via the Internet).

[0114] The flowcharts and block diagrams in the accompanying drawings illustrate the possible implementation 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 can represent a module, program segment, or a part of code, and the above-mentioned module, program segment, or a part of 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 can also occur in an order different from that 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.

[0115] Those skilled in the art will appreciate that the features described in the various embodiments and / or claims of the present invention may be combined and / or coupled in various ways, even if such combinations and / or couplings are not explicitly described in the present invention. In particular, the features described in the various embodiments and / or claims of the present invention may be combined and / or coupled in various ways without departing from the spirit and teachings of the present invention. All such combinations and / or couplings fall within the scope of the present invention.

[0116] The embodiments of the present invention have been described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention. Although each embodiment has been described separately above, this does not mean that the measures in each embodiment cannot be advantageously used in combination. The scope of the present invention is defined by the appended claims and their equivalents. 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 method for determining the refracted light path of a multi-transmitter multi-receiver radar, comprising: Obtaining a range matrix of radar imaging in a preset coordinate system according to a detection cross-section area of ​​the radar, wherein the range matrix includes a plurality of scatterers; For each scatterer, calculating the single-side optical path information corresponding to the scatterer, and obtaining the single-side optical path information of multiple scatterers; as well as determining a refracted light path according to the single-side optical path information of the plurality of scatterers; The unilateral optical path information is the time delay information of the electromagnetic wave propagating from the antenna position to the scatterer; the unilateral optical path information corresponding to the scatterer includes the unilateral optical path information of each antenna corresponding to the scatterer.

2. The method according to claim 1, wherein The preset coordinate system is obtained in the following way: Setting a vacuum and soil layer model for the area detected by the radar; and Based on the vacuum and soil layering model, the preset coordinate system is established according to the detection area and the antenna position.

3. The method according to claim 1, further comprising: The single-side optical path information corresponding to the scatterer is calculated based on the shortest optical path principle.

4. An imaging method comprising: Acquire a refracted optical path, where the refracted optical path includes a set of optical path information, where the optical path information includes single-side optical path information corresponding to each antenna; determining propagation delay information of a plurality of electromagnetic waves based on the set of optical path information; Obtaining a plurality of aligned scatterer signals according to propagation delay information of the plurality of electromagnetic waves; as well as generating a target image by cross-correlation according to the aligned multiple scatterer signals; The refracted light path is obtained by using the refracted light path determination method for a multi-transmitter multi-receiver radar according to any one of claims 1 to 3.

5. The method according to claim 4, wherein The single-side optical path information includes optical path information of a transmitting side and optical path information of a receiving side; and determining propagation delay information of a plurality of electromagnetic waves based on a set of the optical path information includes: For any electromagnetic wave, calculating the total time delay of the electromagnetic wave according to the optical path information of the transmitting side and the optical path information of the receiving side; and The total time delay is used as the propagation delay information of any one of the electromagnetic waves.

6. The method according to claim 5, wherein: Obtaining a plurality of aligned scatterer signals according to the propagation delay information of the plurality of electromagnetic waves includes: Compensation alignment processing is performed according to the total time delay to obtain a plurality of aligned scatterer signals.

7. The method according to claim 4, wherein: Generating a target image by cross-correlation based on the aligned multiple scatterer signals includes: Obtaining brightness information of each scatterer in the range matrix using a cross-correlation method based on the aligned multiple scatterer signals; and A target image is generated according to the brightness information.

8. A device for determining the refracted optical path of a multi-transmitter multi-receiver radar, comprising: A first obtaining module is configured to obtain a range matrix of radar imaging in a preset coordinate system according to a detection cross-section area of ​​the radar, wherein the range matrix includes a plurality of scatterers; A second obtaining module is configured to calculate the single-side optical path information corresponding to each scatterer, and obtain the single-side optical path information of multiple scatterers; as well as A first determining module is configured to determine a refracted light path based on the single-side optical path information of the plurality of scatterers; The unilateral optical path information is the time delay information of the electromagnetic wave propagating from the antenna position to the scatterer; the unilateral optical path information corresponding to the scatterer includes the unilateral optical path information of each antenna corresponding to the scatterer.

9. An imaging device comprising: A first acquisition module is configured to acquire a refracted optical path, wherein the refracted optical path includes a set of optical path information, wherein the optical path information includes single-side optical path information corresponding to each antenna; a second determining module, configured to determine propagation delay information of a plurality of electromagnetic waves based on the set of optical path information; an alignment processing module, configured to obtain a plurality of aligned scatterer signals according to propagation delay information of the plurality of electromagnetic waves; as well as An image generation module is used to generate a target image by using a cross-correlation method based on the aligned multiple scatterer signals; Wherein, the refracted light path is obtained by using the refracted light path determination device of the multi-transmitter and multi-receiver radar according to claim 8.

10. An electronic device comprising: at least one processor; as well as a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method according to any one of claims 1 to 7.

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