Far-field equivalent large-size target LRCS measuring device and method
By using a small rectified linear array laser light source and detection module for linear array scanning in large-size target measurement, the problem of difficulty in achieving far-field equivalent LRCS measurement in the prior art is solved, and the precise evaluation of large-size targets is achieved.
Patent Information
- Application Number
- CN202411727004.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-28
- Publication Date
- 2025-03-11
AI Technical Summary
The prior art is difficult to achieve far-field equivalent lidar scattering cross-section (LRCS) measurement in large-size target measurements, resulting in a large numerical error of measured LRCS.
A linear array laser light source with a small quasi-right angle and a detection module are placed on a linear track. The linear array scanning of a large-size target is completed by moving the linear array laser light source, and the correspondence relationship between the laser echo signal received by the detection module and the position coordinates of the linear track are processed, and the LRCS value of the large-size target is accumulated.
The far-field test conditions are realized at a close distance, and the far-field equivalent LRCS of large-size targets are accurately evaluated, which solves the problem that the light source beam expansion and divergence angle are difficult to take into account, the far-field test conditions are not equivalently realized, and the data processing error is large.
Smart Images
Figure CN119596272A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of laser LRCS measurement, and in particular to a far-field equivalent large-size target LRCS measurement device and method. Background Art
[0002] Lidar scattering cross section (LRCS) is the main information for Lidar target detection and identification. In the existing target close-range far-field equivalent LRCS measurement, the circular laser spot emitted by the irradiating laser light source completely covers the target after beam expansion, and the laser echo after scattering by the target enters the detector field of view. The LRCS value of the measured target is obtained by analyzing the voltage change of the detector. When measuring small-sized targets (meter level and below), this method can cover the target with a small divergence angle in the target area after small-angle beam expansion, forming the far-field test equivalent condition of collimated illumination; however, when measuring large-sized targets (above 15 meters), it is necessary to make the circular laser spot completely cover the target at a close distance, and the irradiating laser light source needs to irradiate the target with a larger divergence angle. In this state, the divergence angle of the irradiating laser light source is too different from the real far-field collimated illumination state, and cannot meet the far-field equivalent test conditions of collimated illumination, resulting in a large error in the measured LRCS value compared with the real far-field illumination condition. As the size of LRCS test targets continues to increase, existing LRCS measurement methods cannot accurately measure far-field equivalent LRCS, which limits the precise evaluation of large-size target LRCS. Therefore, it is urgent to provide a far-field equivalent large-size target LRCS measurement device and method. Summary of the invention
[0003] The invention provides a far-field equivalent large-size target LRCS measurement device and method, wherein the device realizes accurate evaluation of the far-field equivalent LRCS of a large-size target under the condition of realizing far-field testing at a close distance.
[0004] In the first aspect, the present invention provides a far-field equivalent large-size target LRCS measurement device, comprising: a linear array laser light source, a detection module and a linear track; the collimation angle of the linear array laser light source does not exceed 3°; the linear array laser light source and the detection module are both placed on the linear track and move synchronously; the large-size target to be measured is located within the field of view of the linear array laser light source and the detection module.
[0005] Preferably, the detection module includes a visible light detector and an infrared detector.
[0006] Preferably, the detection module is also used to receive the wavelength signal of the linear array laser light source.
[0007] Preferably, the linear array laser light source and the detection module are placed closely together.
[0008] Preferably, it further comprises a control module, wherein the control module is used to control the movement of the linear array laser light source and the detection module.
[0009] Preferably, the linear track is provided with a scale.
[0010] In a second aspect, the present invention further provides a far-field equivalent large-size target LRCS measurement method using any one of the above-mentioned devices, the method comprising:
[0011] According to the position information of the large-size target to be measured, the linear array laser light source and the detection module are determined so that the large-size target to be measured is located within the field of view of the linear array laser light source and the detection module;
[0012] Determining the moving length of the linear array laser light source and the detection module on the linear track according to the size information of the large-size target to be measured and the field of view;
[0013] Placing the linear array laser light source and the detection module at one end of the linear track, turning on the linear array laser light source and the detection module, and then synchronously moving the linear array laser light source and the detection module along the linear track until the moving distance is the same as the moving length;
[0014] The echo signals received by the detection module are accumulated to obtain the LRCS value of the large-size target to be detected.
[0015] Preferably, a control module is used to control the linear array laser light source and the detection module to move at a uniform speed on the linear track.
[0016] Preferably, after turning on the linear array laser light source and the detection module, the method further includes: synchronously recording the position information and the echo signal of the detection module.
[0017] Preferably, accumulating the echo signals received by the detection module to obtain the LRCS value of the large-size target to be detected includes:
[0018] Analyze and process the echo signal at each position information of the detection module to obtain the LRCS value at each position information;
[0019] The LRCS value at each position information is accumulated to obtain the LRCS value of the large-size target to be measured.
[0020] Compared with the prior art, the present invention has at least the following beneficial effects:
[0021] The present invention provides a far-field equivalent large-size target LRCS measurement device and method. A linear array laser light source and a detection module with a small collimation angle are placed on a linear track. During measurement, the linear array laser light source can move on the linear track to complete the linear array scanning of the large-size target. Then, each column of the linear array laser echo signal is processed through the correspondence between the laser echo signal received by the detection module and the linear track position coordinates, and then the LRCS data of the large-size target can be obtained by integration. In this way, the far-field equivalent large-size target LRCS measurement is completed by scanning the linear array laser light source, and the far-field test conditions can be achieved at a close distance. The far-field equivalent LRCS of the large-size target is accurately evaluated, which solves the problems of the difficulty in taking into account the beam expansion and divergence angle of the light source in the previous far-field equivalent large-size target LRCS measurement, the inability to achieve equivalent far-field test conditions, and large data processing errors. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0023] Figure 1 It is a schematic diagram of a far-field equivalent large-size target LRCS measurement device provided by an embodiment of the present invention;
[0024] Figure 2 It is a flow chart of a far-field equivalent large-size target LRCS measurement method provided by one embodiment of the present invention;
[0025] Reference numerals: 10 - linear array laser light source; 20 - detection module; 30 - linear track; 40 - large-size target to be detected. DETAILED DESCRIPTION
[0026] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.
[0027] Please refer to Figure 1An embodiment of the present invention provides a far-field equivalent large-size target LRCS measurement device, comprising: a linear array laser light source 10, a detection module 20 and a linear track 30; the collimation angle of the linear array laser light source 10 does not exceed 3°; the linear array laser light source 10 and the detection module 20 are both placed on the linear track 30 and move synchronously; the large-size target 40 to be measured is located within the field of view of the linear array laser light source 10 and the detection module 20.
[0028] In an embodiment of the present invention, a linear array laser light source with a small collimation angle and a detection module are placed on a linear track. During measurement, the linear array laser light source can move on the linear track to complete a linear array scan of a large-sized target. Then, each column of the linear array laser echo signal is processed through the correspondence between the laser echo signal received by the detection module and the linear track position coordinates, and then the LRCS data of the large-sized target can be obtained by integration. In this way, the far-field equivalent large-sized target LRCS measurement is completed by scanning with a linear array laser light source, and the far-field test conditions can be achieved at a close distance, and the far-field equivalent LRCS of the large-sized target can be accurately evaluated, which solves the problems of the difficulty in balancing the light source beam expansion and divergence angle, the inability to achieve equivalent far-field test conditions, and large data processing errors in the previous far-field equivalent large-sized target LRCS measurement.
[0029] In the present invention, a linear array laser light source with a collimation angle not exceeding 3° is selected to prevent the echo signal returned by the divergent laser from affecting the accuracy of the LRCS measurement result.
[0030] In a preferred embodiment, the detection module 20 includes a visible light detector and an infrared detector.
[0031] In a preferred embodiment, the detection module 20 is also used to receive the wavelength signal of the linear array laser light source.
[0032] In a preferred embodiment, Figure 1 As shown, the linear array laser light source 10 and the detection module 20 are placed closely together.
[0033] Specifically, the linear array laser light source and the detection module can be placed side by side or side by side, and the linear array laser light source and the detection module remain relatively still during the movement.
[0034] In a preferred embodiment, the device further includes a control module, and the control module is used to control the movement of the linear array laser light source 10 and the detection module 20.
[0035] In the present invention, in order to accurately control the movement of the linear array laser light source and the detection module, it is selected to control their uniform motion through a control module.
[0036] In a preferred embodiment, a scale is provided on the linear track 30 .
[0037] In the present invention, the specific position information of the linear array laser light source and the detection module during movement is further determined by setting scales on the linear track, so that the echo signals obtained according to each position information are subsequently accumulated in a specific order to obtain the complete LRCS value of the large-size target to be measured.
[0038] like Figure 2 As shown, the present invention also provides a far-field equivalent large-size target LRCS measurement method, comprising:
[0039] Step 200, determining a linear array laser light source and a detection module according to the position information of the large-size target to be measured, so that the large-size target to be measured is located within the field of view of the linear array laser light source and the detection module;
[0040] Step 202, determining the moving length of the linear array laser light source and the detection module on the linear track according to the size information and field of view of the large-size target to be measured;
[0041] Step 204, placing the linear array laser light source and the detection module at one end of the linear track, turning on the linear array laser light source and the detection module, and then synchronously moving the linear array laser light source and the detection module along the linear track until the moving distance is the same as the moving length;
[0042] Step 206: Accumulate the echo signals received by the detection module to obtain the LRCS value of the large-size target to be detected.
[0043] It should be noted that in order to ensure that the large-size target to be measured is within the field of view of the linear array laser light source and the detection module, it is necessary to select a matching linear array laser light source and detection module according to the distance between the large-size target to be measured and the linear array laser light source. At the same time, it is also necessary to select a detection module whose field of view matches the linear array laser light source, that is, to ensure that the detection module can receive the wavelength signal of the linear array laser light source.
[0044] In the present invention, since the size of the large-size target to be measured is more than 15 meters, the linear array laser light source needs to further determine the minimum length of the linear track (i.e., the moving length) according to the size information, position information and field of view of the large-size target during mobile scanning. As long as the length of the linear track is not less than the minimum length, the LRCS measurement of the large-size target to be measured can be achieved.
[0045] It should be noted that when the moving distance and moving length of the linear array laser light source and the detection module are the same, the LRCS coverage acquisition of the large-size target to be measured is completed.
[0046] In a preferred embodiment, in step 204, a control module is used to control the linear array laser light source and the detection module to move at a uniform speed on a linear track.
[0047] In a preferred embodiment, in step 204, after the linear array laser light source and the detection module are turned on, the step further includes: synchronously recording the position information and the echo signal of the detection module.
[0048] In a preferred embodiment, step 206, accumulating the echo signals received by the detection module to obtain the LRCS value of the large-size target to be detected, includes:
[0049] Analyze and process the echo signal at each position information of the detection module to obtain the LRCS value at each position information;
[0050] The LRCS value at each position information is accumulated to obtain the LRCS value of the large-size target to be measured.
[0051] In the present invention, each column of echo signals is processed through the correspondence between the linear array laser echo signals and the position coordinates of the detection modules on the linear track, and the processed echo signals are integrated according to the moving direction to obtain the LRCS data of the large-size target to be measured.
[0052] It is to be understood that the structure illustrated in the embodiment of the present invention does not constitute a specific limitation on a far-field equivalent large-size target LRCS measurement device. In other embodiments of the present invention, a far-field equivalent large-size target LRCS measurement device may include more or fewer components than shown in the figure, or combine some components, or split some components, or arrange the components differently.
[0053] It should be noted that, in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise a ..." do not exclude the presence of other identical factors in the process, method, article or device including the elements.
[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A far-field equivalent large-size target LRCS measurement device, characterized in that: include: A linear array laser light source, a detection module and a linear track; the collimation angle of the linear array laser light source does not exceed 3°; the linear array laser light source and the detection module are both placed on the linear track and move synchronously; the large-size target to be measured is located within the field of view of the linear array laser light source and the detection module.
2. The far-field equivalent large-size target LRCS measurement device according to claim 1 is characterized in that: The detection module includes a visible light detector and an infrared detector.
3. The far-field equivalent large-size target LRCS measurement device according to claim 1 is characterized in that: The detection module is also used to receive the wavelength signal of the linear array laser light source.
4. The far-field equivalent large-size target LRCS measurement device according to claim 1 is characterized in that: The linear array laser light source and the detection module are placed closely together.
5. The far-field equivalent large-size target LRCS measurement device according to claim 1, characterized in that: It also includes a control module, which is used to control the movement of the linear array laser light source and the detection module.
6. The far-field equivalent large-size target LRCS measurement device according to any one of claims 1 to 5, characterized in that: The linear track is provided with scales.
7. A measurement method using the far-field equivalent large-size target LRCS measurement device described in any one of claims 1 to 6, characterized in that: include: According to the position information of the large-size target to be measured, the linear array laser light source and the detection module are determined so that the large-size target to be measured is located within the field of view of the linear array laser light source and the detection module; Determining the moving length of the linear array laser light source and the detection module on the linear track according to the size information of the large-size target to be measured and the field of view; Placing the linear array laser light source and the detection module at one end of the linear track, turning on the linear array laser light source and the detection module, and then synchronously moving the linear array laser light source and the detection module along the linear track until the moving distance is the same as the moving length; The echo signals received by the detection module are accumulated to obtain the LRCS value of the large-size target to be detected.
8. The method according to claim 7, characterized in that include: A control module is used to control the linear array laser light source and the detection module to move at a uniform speed on the linear track.
9. The method according to claim 7 or 8, characterized in that After the linear array laser light source and the detection module are turned on, the method further includes: synchronously recording the position information and the echo signal of the detection module.
10. The method according to claim 9, characterized in that The step of accumulating the echo signals received by the detection module to obtain the LRCS value of the large-size target to be detected includes: Analyze and process the echo signal at each position information of the detection module to obtain the LRCS value at each position information; The LRCS value at each position information is accumulated to obtain the LRCS value of the large-size target to be measured.