Multi-quantum state target scattering characteristic measurement system and method

Abstract

The application discloses a kind of multi-quantum state target scattering characteristic measurement systems, comprising: laser emission system;Multi-quantum state target echo signal, for obtaining the coherent state scattering echo energy of target and ground object background, the photon number state scattering echo energy and the polarization state scattering echo energy according to the scattering echo beam of target and ground object background;Scattering characteristic analysis system, for the echo energy of three quantum states of target and ground object background as the three vector values of three-dimensional coordinates, and fusion into three-dimensional graph, analyze the difference of target and ground object background scattering characteristic.The application has the advantages of wide measurement data, high measurement data accuracy, low test cost and other advantages, overcomes the single disadvantage of traditional quantum laser radar measurement state, fills the blank of target quantum scattering characteristic measurement of target in ground object environment, provides a new method for identification of target based on quantum laser radar in complex environment.

Description

Technical Field

[0001] This invention relates to the field of optical scattering transmission testing technology, and in particular to a method for measuring the scattering characteristics of multi-quantum-state targets in a ground-based quantum lidar. Background Technology

[0002] Quantum radar is a novel radar system combining radar technology with quantum technology. It fully utilizes the quantum properties of electromagnetic fields to overcome the performance limits of classical detection, while also possessing more information dimensions, thus showing broad application prospects. Research on the scattering characteristics of quantum targets will provide strong support for the design and use of quantum radar, enabling a reasonable evaluation of the effectiveness and improvement methods of quantum radar target detection. It will also provide more information for target identification from the quantum state dimension. The manifestation of target characteristics will differ depending on the characteristics of different quantum state signals, and quantum target characteristics will present different focuses and characterization methods compared to classical radar target characteristics.

[0003] In existing research on the measurement of multi-quantum-state target scattering characteristics using quantum lidar, no research reports have been found on measurement methods for ground backgrounds; only research on measurement methods for single quantum states has been found. Moreover, traditional testing methods typically only use quantum lidar to test a single quantum state on a single target, without considering the influence of the surrounding environment on the target. Summary of the Invention

[0004] This invention proposes a quantum lidar multi-quantum-state target scattering characteristic measurement system and method. The system obtains quantum state data of the coherent state, photon number state, and polarization state scattering characteristics of the target and the ground background through a multi-path optical receiving system. The obtained multi-quantum-state data are then fused to analyze the differences in scattering characteristics between the target and the ground background.

[0005] To achieve the above objectives, this invention proposes a quantum lidar multi-quantum-state target scattering characteristic measurement system, comprising:

[0006] A laser emitting system used to generate a laser beam with adjustable polarization direction and beam size, and to illuminate a target and / or ground background.

[0007] A multi-quantum-state target echo signal receiving system is used to receive the scattered echo beams of the target and the ground background to obtain the coherent state scattered echo energy, photon number state scattered echo energy and polarization state scattered echo energy of the target and the ground background.

[0008] The scattering characteristic analysis system is used to analyze the differences in scattering characteristics between the target and the ground background based on the coherent state scattering echo energy, photon number state scattering echo energy, and polarization state scattering echo energy.

[0009] Furthermore, the laser emitting system includes:

[0010] A laser, which is used to emit laser light;

[0011] An adjustable lens group is used to adjust the divergence angle of the laser beam, thereby adjusting the beam size when the laser beam illuminates the target or ground background.

[0012] A first polarizer is used to change the polarization direction of the laser.

[0013] Furthermore, the laser is a fiber laser.

[0014] Furthermore, the multi-quantum-state target echo signal receiving system includes:

[0015] The coherent state receiving module is used to receive the echo beams scattered from the background of the target and ground objects to generate target scattered echo energy and ground object background scattered echo energy with coherent state.

[0016] The photon number state receiving module receives the echo beams scattered from the target and the background of ground objects, respectively, to generate the photon number state scattered echo energy of the target and the photon number state scattered echo energy of the background of ground objects.

[0017] The polarization state receiving module is used to generate the polarization state echo energy of the target and the polarization state echo energy of the ground background.

[0018] Furthermore, the coherent state receiving module includes a pump light source, a lithium niobate crystal, a diffraction grating, a beam splitter, and a single-photon counter connected in sequence.

[0019] The pump light source generates pump light and outputs it to the lithium niobate crystal;

[0020] The lithium niobate crystal is used to combine the pump light with the scattered echo beams of the target and the ground background to obtain a combined beam.

[0021] The diffraction grating and fractionator are used to separate the combined beam to obtain the target scattered echo energy and the ground background scattered echo energy with coherent state.

[0022] The single-photon counter is used to measure the coherent state scattered echo beam of the target and the coherent state scattered echo beam of the ground background, respectively.

[0023] Furthermore, the photon counting and receiving module includes: a first photon counter and a first signal processor connected in sequence, wherein the first photon counter is used to receive and measure the echo beams scattered by the background of the target and the ground objects respectively;

[0024] The first signal processor is used to process the signal obtained by the first photon counter.

[0025] Furthermore, the polarization state receiving module includes a second polarizer, a second photon counter, and a second signal processor connected in sequence;

[0026] The second polarizer is used to change the polarization direction of the scattered echo beam from the target and the ground background;

[0027] The second photon counter is used to measure the echo beams scattered from the background of the target and ground objects, respectively;

[0028] The second signal processor is used to process the signal obtained by the second photon counter.

[0029] Based on the same concept, this invention also proposes a method for measuring the scattering characteristics of a target using the above-mentioned multi-quantum-state target scattering characteristic measurement system, comprising the following steps:

[0030] The polarization angle of the laser beam was adjusted within the range of 0 to 90 degrees. The coherent state scattering echo energy, photon number state scattering echo energy, and polarization state scattering echo energy of the target and ground background were measured and obtained multiple times. The echo energies of the three quantum states of the target and ground background were used as three vector values ​​of the three-dimensional coordinates and fused into the three-dimensional map to analyze the differences in scattering characteristics of the target and ground background.

[0031] Furthermore, the method for obtaining the coherent state scattered echo energy, photon number state scattered echo energy, and polarization state scattered echo energy of the target and ground background includes the following steps:

[0032] S1. Rotate the first polarizer, and the laser emission system emits a beam with a certain polarization angle;

[0033] S2. Adjust the divergence angle of the beam so that the beam fully illuminates the target and the background of the ground features. The scattered echo beams of the target and the background of the ground features are received by the coherent state receiving module to obtain the coherent state scattered echo energy of the target and the background of the ground features.

[0034] S3. Adjust the divergence angle of the beam and illuminate the local area of ​​the target and the background of the ground objects respectively. The scattered echo beams of the target and the background of the ground objects are received by the photon number state receiving module in turn to obtain the photon number state scattered echo energy of the target and the background of the ground objects.

[0035] S4. Adjust the divergence angle of the beam and illuminate the local area of ​​the target and the background of the ground objects respectively. The scattered echo beams of the target and the background of the ground objects are received by the polarization state receiving module in turn. Rotate the second polarizer to obtain the polarization state scattered echo energy of the target and the background of the ground objects.

[0036] S5. Repeat steps S1-S4, adjusting the polarization angle of the laser beam within the range of 0 to 90 degrees, and take multiple measurements.

[0037] This invention has the following advantages:

[0038] The multi-quantum-state target scattering characteristic measurement system of this invention can obtain the coherent state, photon number state, and polarization state scattering characteristics of the target and the surrounding environment. It uses the data from these three quantum states as three vector components of a three-dimensional coordinate system, fusing the data within the three-dimensional coordinates to discover differences in the background scattering characteristics of the target and the surrounding environment, thus providing a new technical means for target identification. This invention has advantages such as extensive measurement data, high measurement accuracy, and low testing cost, overcoming the disadvantage of traditional quantum lidar's relatively singular measurement states. It fills the gap in measuring the quantum scattering characteristics of targets in complex environments and provides a new method for target identification in complex environments based on quantum lidar. Attached Figure Description

[0039] Figure 1 A schematic diagram of the structure of the multi-quantum-state target scattering characteristic measurement system provided by the present invention;

[0040] Figure 2 A schematic diagram of a 3D image is generated by fusing the echo energies of the three quantum states of the target and the background objects as three vector values ​​of the three-dimensional coordinates.

[0041] Figure 3 This is a flowchart illustrating the multi-quantum-state target scattering characteristic measurement method provided by the present invention. Detailed Implementation

[0042] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer from the following description and claims. It should be noted that the drawings are all in a very simplified form and use non-precise ratios, and are only used to facilitate and clarify the illustration of the embodiments of the present invention.

[0043] To address the aforementioned problems encountered in measuring the scattering characteristics of multi-quantum-state targets using quantum lidar with ground background, this invention proposes a measurement system that combines different optical path receiving system structures to obtain the coherent state, photon number state, and polarization state of the target. The system then integrates the obtained multi-quantum-state data to analyze the differences in scattering characteristics between the target and the ground background.

[0044] like Figure 1As shown, the multi-quantum-state target scattering characteristic measurement system includes a laser emission system, a multi-quantum-state target echo signal receiving system, and a scattering characteristic analysis system 14. The laser emission system emits a laser beam with adjustable polarization direction and beam size, illuminating the target and / or ground background. The multi-quantum-state target echo signal receiving system receives the scattered echo beams from the target and ground background to obtain the coherent state scattered echo energy, photon number state scattered echo energy, and polarization state scattered echo energy of the target and ground background. The scattering characteristic analysis system 14 uses the obtained coherent state scattered echo energy, photon number state scattered echo energy, and polarization state scattered echo energy of the target and ground background as three vector values ​​of a three-dimensional coordinate system and integrates them into a three-dimensional graph, as shown below. Figure 2 As shown, this is to analyze the differences in background scattering characteristics between the target and ground features.

[0045] Specifically, the laser emitting system includes: a laser 1 for emitting laser light; an adjustable lens group 2 for adjusting the divergence angle of the laser beam, thereby adjusting the beam size when the laser beam illuminates a target or ground background; and a first polarizer 3 for changing the polarization direction of the laser beam. Preferably, the laser 1 is a fiber laser.

[0046] The multi-quantum-state target echo signal receiving system includes: a coherent state receiving module, a photon number state receiving module, and a polarization state receiving module. The coherent state receiving module, the photon number state receiving module, and the polarization state receiving module generate the coherent state scattered echo energy, the photon number state scattered echo energy, and the polarization state echo energy of the target and the ground background, respectively, based on the echo beams scattered by the target and the ground background.

[0047] Furthermore, the coherent state receiving module includes a pump light source 4, a lithium niobate crystal 5, a diffraction grating 6, a beam splitter 7, and a single-photon counter 8 connected in sequence. The pump light source 4 generates pump light and outputs it to the lithium niobate crystal 5; the pump light interacts with the scattered echo beam of the target and the scattered echo of the ground background, respectively, to generate a combined frequency beam of the scattered echo of the target and the ground background, resulting in a mixed frequency beam; the diffraction grating 6 and the beam splitter 7 are used to separate the mixed frequency beam to obtain the target scattered echo energy and the ground background scattered echo energy with coherent state; the single-photon counter 8 is used to measure the coherent state scattered echo beam of the target and the coherent state scattered echo beam of the ground background, respectively.

[0048] The photon counting and receiving module includes a first photon counter 9 and a first signal processor 10 connected in sequence. The first photon counter 9 is used to receive and measure the echo beams scattered by the background of the target and the ground object, respectively. The first signal processor 10 is used to process the signals obtained by the first photon counter 9.

[0049] The polarization state receiving module includes a second polarizer 11, a second photon counter 12, and a second signal processor 13 connected in sequence; the second polarizer 11 is used to change the polarization direction of the scattered echo beams of the target and the ground background; the second photon counter 12 is used to measure the echo beams scattered by the target and the ground background respectively; and the second signal processor 13 is used to process the signals obtained by the photon counter.

[0050] like Figure 3 As shown, this invention also proposes a method for measuring the scattering characteristics of a multi-quantum-state target, comprising the following steps:

[0051] S1. Rotate the first polarizer 3, and the laser emission system emits a beam with a certain polarization angle;

[0052] S2. Adjust the divergence angle of the beam so that the beam fully illuminates the target and the background of the ground features. The scattered echo beams of the target and the background of the ground features are received by the coherent state receiving module to obtain the coherent state scattered echo energy of the target and the background of the ground features.

[0053] S3. Adjust the divergence angle of the beam and illuminate the local area of ​​the target and the background of the ground objects respectively. The scattered echo beams of the target and the background of the ground objects are received by the photon number state receiving module in turn to obtain the photon number state scattered echo energy of the target and the background of the ground objects.

[0054] S4. Adjust the divergence angle of the beam and illuminate the local area of ​​the target and the background of the ground objects respectively. The scattered echo beams of the target and the background of the ground objects are received by the polarization state receiving module in turn. Rotate the second polarizer 11 to obtain the polarization state scattered echo energy of the target and the background of the ground objects.

[0055] S5. Repeat steps S1-S4, adjusting the polarization angle of the laser beam within the range of 0 to 90 degrees, and take multiple measurements; specifically, repeat the measurement 1000 times.

[0056] S6. The echo energies of the three quantum states of the target and the background are used as three vector values ​​of the three-dimensional coordinates and fused into the three-dimensional map to analyze the differences in the scattering characteristics of the target and the background.

[0057] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A multi-quantum-state target scattering characteristic measurement system, characterized in that, Include: A laser emitting system used to generate a laser beam with adjustable polarization direction and beam size, and to illuminate a target and / or ground background. A multi-quantum-state target echo signal receiving system is used to receive the scattered echo beams of the target and the ground background to obtain the coherent state scattered echo energy, photon number state scattered echo energy and polarization state scattered echo energy of the target and the ground background. The scattering characteristic analysis system is used to obtain the coherent state scattering echo energy, photon number state scattering echo energy, and polarization state scattering echo energy of the target and ground background. The data of the three quantum states are used as three vector components of a three-dimensional coordinate system to analyze the differences in scattering characteristics between the target and ground background. The multi-quantum-state target echo signal receiving system includes: The coherent state receiving module is used to receive the echo beams scattered from the background of the target and ground objects to generate target scattered echo energy and ground object background scattered echo energy with coherent state. The photon number state receiving module receives the echo beams scattered from the target and the background of ground objects, respectively, to generate the photon number state scattered echo energy of the target and the photon number state scattered echo energy of the background of ground objects. A polarization state receiving module, which is used to generate the polarization state echo energy of the target and the polarization state echo energy of the ground background; The coherent state receiving module includes a pump light source, a lithium niobate crystal, a diffraction grating, a beam splitter, and a single-photon counter connected in sequence. The pump light source generates pump light and outputs it to the lithium niobate crystal; The lithium niobate crystal is used to combine the pump light with the scattered echo beams of the target and the ground background to obtain a combined beam. The diffraction grating and fractionator are used to separate the combined beam to obtain the target scattered echo energy and the ground background scattered echo energy with coherent state. The single-photon counter is used to measure the coherent state scattered echo energy of the target and the coherent state scattered echo energy of the ground background, respectively. The photon counting and receiving module includes: a first photon counter and a first signal processor connected in sequence; the first photon counter is used to receive and measure the echo beams scattered by the background of the target and ground objects respectively; the first signal processor is used to process the signals obtained by the first photon counter. The polarization state receiving module includes a second polarizer, a second photon counter, and a second signal processor connected in sequence; the second polarizer is used to change the polarization direction of the scattered echo beams of the target and the ground background; the second photon counter is used to measure the echo beams scattered by the target and the ground background respectively; and the second signal processor is used to process the signal obtained by the second photon counter.

2. The multi-quantum-state target scattering characteristic measurement system as described in claim 1, characterized in that, The laser emitting system includes: A laser, which is used to emit laser light; An adjustable lens group is used to adjust the divergence angle of the laser beam, thereby adjusting the beam size when the laser beam illuminates the target or ground background. A first polarizer is used to change the polarization direction of the laser.

3. The multi-quantum-state target scattering characteristic measurement system as described in claim 2, characterized in that, The laser is a fiber laser.

4. A method for measuring target scattering characteristics using the multi-quantum-state target scattering characteristic measurement system according to any one of claims 1-3, characterized in that, Includes the following steps: The polarization angle of the laser beam was adjusted within the range of 0 to 90 degrees, and the coherent state scattering echo energy, photon number state scattering echo energy, and polarization state scattering echo energy of the target and ground background were measured and obtained multiple times. The echo energies of the three quantum states of the target and ground background were used as three vector values ​​of the three-dimensional coordinates and fused into the three-dimensional map to analyze the differences in the scattering characteristics of the target and ground background.

5. The method for measuring the scattering characteristics of a multi-quantum-state target as described in claim 4, characterized in that, The method for obtaining the coherent state scattered echo energy, photon number state scattered echo energy, and polarization state scattered echo energy of the target and ground background includes the following steps: S1. Rotate the first polarizer, and the laser emission system emits a beam with a certain polarization angle; S2. Adjust the divergence angle of the beam so that the beam fully illuminates the target and the background of the ground features. The scattered echo beams of the target and the background of the ground features are received by the coherent state receiving module to obtain the coherent state scattered echo energy of the target and the background of the ground features. S3. Adjust the divergence angle of the beam and illuminate the local area of ​​the target and the background of the ground objects respectively. The scattered echo beams of the target and the background of the ground objects are received by the photon number state receiving module in turn to obtain the photon number state scattered echo energy of the target and the background of the ground objects. S4. Adjust the divergence angle of the beam and illuminate the local area of ​​the target and the background of the ground objects respectively. The scattered echo beams of the target and the background of the ground objects are received by the polarization state receiving module in turn. Rotate the second polarizer to obtain the polarization state scattered echo energy of the target and the background of the ground objects. S5. Repeat steps S1-S4, adjusting the polarization angle of the laser beam within the range of 0 to 90 degrees, and take multiple measurements.

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