Atmospheric waveguide laser radar testing device and testing method

Abstract

An atmospheric waveguide laser radar testing device comprises a testing box, an incident mechanism used for introducing a testing light beam emitted by a laser radar into the testing box, an environment construction mechanism used for forming a testing environment in the testing box, and an emergent mechanism used for leading out an echo light beam from the testing box to the laser radar. The incident mechanism comprises a laser filter and a first optical fiber which are sequentially arranged along the irradiation direction of the test light beam; the environment construction mechanism comprises an environment factor control assembly for forming a test environment in the test box and an environment factor sensing assembly for sensing the test environment; the emitting mechanism comprises a third lens installed on the test box, a second optical fiber used for sending the echo light beam in the test box back to the laser radar, and a fourth lens used for collimating the echo light beam. The device can accurately test the atmospheric waveguide laser radar, is simple in structure and easy to carry, and has no complex requirements on a test site.

Description

Technical Field

[0001] The invention relates to the technical field of atmospheric waveguide laser radar, in particular to an atmospheric waveguide laser radar testing device and a testing method. Background Art

[0002] Atmospheric waveguide lidar is a laser radar specially used for atmospheric electromagnetic environment detection. Its main physical quantities include atmospheric temperature, atmospheric humidity and atmospheric corrected refractive index. At present, atmospheric waveguide lidar has been widely used in electromagnetic environment monitoring, meteorological environment monitoring and other fields.

[0003] At present, the performance test of atmospheric waveguide lidar is mainly based on radiosonde. Radiosonde is usually carried by sounding balloon into the air. During the ascent of the balloon, the atmospheric temperature, humidity and pressure profile are detected, and the atmospheric corrected refractive index profile is calculated. The radiosonde data is compared with the atmospheric waveguide lidar data to obtain the measurement error of the atmospheric waveguide lidar.

[0004] This method has some defects, mainly including: First, the measurement accuracy of the radiosonde is similar to that of the atmospheric waveguide lidar, so the use of the radiosonde as a standard is less effective; second, the process of the radiosonde being launched with the sounding balloon is affected by wind speed and direction, and its ascent process is not a vertical upward profile, which is different from the measurement path of the atmospheric waveguide lidar; third, the sounding balloon cannot be launched at will, and relevant qualifications and approvals must be obtained, resulting in restrictions on the comparison measurement sites, making it difficult to carry out measurement error comparison work at the installation and use sites of the atmospheric waveguide lidar; fourth, launching the sounding balloon and obtaining the radiosonde data requires inflating the sounding balloon with hydrogen or helium, and a ground receiver is required to receive the radiosonde data. The equipment is large in size, heavy in weight, not portable, and difficult to operate. Summary of the invention

[0005] In order to solve the deficiencies in the prior art, the present invention provides an atmospheric waveguide laser radar testing device and a testing method, which can accurately test the atmospheric waveguide laser radar, and have a simple structure, are easy to carry, and have no complex requirements for the test site.

[0006] In order to achieve the above-mentioned object, the specific scheme adopted by the present invention is: an atmospheric waveguide laser radar test device, comprising a test box, an incident mechanism for introducing a test beam emitted by the laser radar into the test box, an environment construction mechanism for forming a test environment inside the test box, and an output mechanism for leading an echo beam from the test box to the laser radar; The incident mechanism comprises a laser filter and a first optical fiber which are sequentially arranged along the irradiation direction of the test light beam; The environment construction mechanism includes an environmental factor control component for forming the test environment in the test box and an environmental factor sensing component for sensing the test environment; The emission mechanism includes a third lens installed on the test box, a second optical fiber used to send the echo light beam in the test box back to the laser radar, and a fourth lens for collimating the echo light beam.

[0007] As a further optimization of the above-mentioned atmospheric waveguide lidar test device: the incident mechanism includes a first lens located in front of the laser filter, and the first lens is used to collect the test light beam.

[0008] As a further optimization of the above-mentioned atmospheric waveguide lidar test device: the incident mechanism includes a second lens located at the output end of the first optical fiber, and the second lens is used to collimate the test light beam.

[0009] As a further optimization of the above-mentioned atmospheric waveguide lidar testing device: the environmental factor control component includes a temperature controller and an air pressure controller, wherein the temperature controller is used to control the temperature in the test box, and the air pressure controller is used to control the air pressure in the test box.

[0010] As a further optimization of the above-mentioned atmospheric waveguide lidar testing device: the environmental factor sensing component includes a temperature sensor and an air pressure sensor, wherein the temperature sensor is used to sense the temperature in the test box, and the air pressure sensor is used to sense the air pressure in the test box.

[0011] As a further optimization of the above-mentioned atmospheric waveguide lidar testing device: the environmental factor sensing component also includes a humidity sensor.

[0012] As a further optimization of the above-mentioned atmospheric waveguide lidar test device: the inner wall of the test box is coated with a matte coating, and the outer wall of the test box is provided with a thermal insulation layer.

[0013] As a further optimization of the above-mentioned atmospheric waveguide lidar test device: a beam collector is arranged in the test box in the irradiation direction of the test beam.

[0014] An atmospheric waveguide laser radar test method is based on the above-mentioned atmospheric waveguide laser radar test device, and the method comprises the following steps: The energy of the test beam is adjusted to a target energy level by adjusting the attenuation magnification of the laser filter; Using the environmental factor control component to form a test environment in the test box, and using the environmental factor sensing component to determine whether the test environment reaches a preset environmental condition; Using the incident mechanism to introduce the test light beam into the test box; The emission mechanism is used to lead the echo light beam from the test box to the receiving component of the laser radar.

[0015] Beneficial effects: The present invention firstly simulates the attenuation of the test beam emitted by the laser radar under the influence of the atmosphere by setting a laser filter, and then determines the reference parameters such as temperature, humidity and air pressure by forming a specific test environment in the test box, and finally determines the measurement error of the laser radar by analyzing and calculating the backscattered light in the Raman scattered light formed by the laser radar to determine the measurement error of the laser radar, so as to test the performance of the laser radar. The present invention can work continuously for a long time, and perform multiple measurements on the parameters required for the test, so as to make the test results more accurate. In addition, the present invention has a simple structure, is portable and easy to use, and has no requirements for the test site. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the structure of the testing device of the present invention; Figure 2 It is a flow chart of the testing method of the present invention.

[0017] Description of the drawings: 1-first lens, 2-laser filter, 3-first optical fiber, 4-detection box, 5-second lens, 6-temperature sensor, 7-humidity sensor, 8-air pressure sensor, 9-beam collector, 10-temperature controller, 11-third lens, 12-air pressure controller, 13-second optical fiber, 14-fourth lens. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] like Figure 1 As shown, an atmospheric waveguide laser radar test device includes a test box 4, an incident mechanism for introducing a test beam emitted by the laser radar into the test box 4, an environment construction mechanism for forming a test environment inside the test box 4, and an output mechanism for leading an echo beam from the test box 4 to the laser radar.

[0020] The incident mechanism comprises a laser filter 2 and a first optical fiber 3 which are sequentially arranged along the irradiation direction of the test light beam.

[0021] The environment construction mechanism includes an environment factor control component for forming a test environment in the test box 4 and an environment factor sensing component for sensing the test environment.

[0022] The emission mechanism includes a third lens 11 mounted on the test box 4, a second optical fiber 13 for sending the echo light beam in the test box 4 back to the laser radar, and a fourth lens 14 for collimating the echo light beam.

[0023] When the laser radar is tested by using the present invention, the laser radar is first turned on, and the test beam emitted by the laser radar is irradiated on the laser filter 2. The test beam is attenuated by the laser filter 2, so as to adjust the energy of the test beam and simulate the attenuation of the test beam due to factors such as atmospheric transmittance, measurement height and geometric overlap factor.

[0024] The attenuated test light beam enters the test box 4 through the first optical fiber 3. In the test box 4, the test light beam will be affected by the gas molecules inside the test box 4, thereby generating Raman scattered light. By changing the test environment, the state of the Raman scattered light can be changed. Parameters such as temperature, humidity and air pressure of the test environment can be recorded as reference parameters. The test environment can be formed in the test box 4 through the environmental factor control component, and the reference parameters of the test environment can be accurately controlled through the environmental factor sensing component.

[0025] Then, the backscattered light in the Raman scattered light forms an echo beam and enters the second optical fiber 13 through the third lens 11. The third lens 11 is used to focus the echo beam into the second optical fiber 13. After passing through the second optical fiber 13, the echo beam is sent back to the receiving component of the laser radar. After that, the laser radar is used to analyze the received echo beam, and the specific parameters of the test environment in the test box 4 can be calculated, including temperature, humidity, and air pressure, etc. The calculated results are recorded as actual parameters, and the atmospheric correction refractive index of the laser radar can be calculated by combining temperature, humidity, and air pressure.

[0026] Finally, by comparing the actual parameters with the reference parameters, we can obtain the errors of the lidar in temperature calculation, humidity calculation, and air pressure calculation, and get the final test results.

[0027] The present invention first sets a laser filter 2 to simulate the attenuation of the test light beam emitted by the laser radar affected by the atmosphere, and then forms a specific test environment in the test box 4 to determine the temperature, humidity, air pressure and other parameters used as references. Finally, the laser radar is used to analyze and calculate the temperature, humidity, air pressure and other parameters of the echo light beam to determine the measurement error of the laser radar, thereby realizing the test of the laser radar performance.

[0028] The present invention can work continuously for a long time and perform multiple measurements on the parameters required for the test, so that the test results are more accurate. In addition, the present invention has a simple structure, is portable and easy to use, and has no requirements on the test site.

[0029] Because the cross section of the first optical fiber 3 is small, in order to ensure that the test beam of sufficient intensity can accurately enter the first optical fiber 3, thereby ensuring the accuracy of the test result, the injection mechanism includes a first lens 1 located in front of the laser filter 2, and the first lens 1 is used to collect the test beam. The first lens 1 and the third lens 11 can both be set as convex lenses, and a convex lens of a suitable size can be selected according to the actual situation of the test beam.

[0030] Furthermore, a beam collector 9 is provided in the test box 4 in the irradiation direction of the test beam, and the beam collector 9 can be used to eliminate useless reflected light and scattered light to reduce the level of stray light and avoid interference with the echo beam. It should be noted that the effective opening size of the beam collector 9 should be larger than the size of the beam irradiated to its surface. In order to ensure that the test beam is irradiated onto the inner wall of the test box 4 without divergence, and can be accurately irradiated onto the beam collector 9 to avoid causing additional errors, the incident mechanism includes a second lens 5 located at the exit end of the first optical fiber 3, and the second lens 5 is used to collimate the test beam. The second lens 5 can be a spherical lens, an aspherical lens, or a double-cemented lens, etc., which is a conventional choice in the art and will not be repeated here. Similarly, in order to ensure that the receiving component of the laser radar can receive the echo beam, the output mechanism includes a fourth lens 14 arranged at the exit end of the second optical fiber 13, and the fourth lens 14 is used to collimate the echo beam. The fourth lens 14 can also be a spherical lens, an aspherical lens, or a double-cemented lens, etc.

[0031] The specific structure of the environmental factor control component is as follows: the environmental factor control component includes a temperature controller 10 and an air pressure controller 12, wherein the temperature controller 10 is used to control the temperature in the test box 4, and the air pressure controller 12 is used to control the air pressure in the test box 4. Among them, the temperature controller 10 can change the temperature of the test environment by electric heating or medium heating. Preferably, the temperature controller 10 uses water as a medium, and can increase the temperature of the test environment by hot water, or reduce the temperature of the test environment by cold water, so that the temperature of the test environment can be controlled more flexibly and accurately. The air pressure controller 12 may include an air source arranged outside or inside the test box 4, and a bidirectional air pump for controlling the air source to transport gas into the test box 4 or to draw the gas in the test box 4 back into the air source. By controlling the bidirectional air pump, the air pressure of the test environment can be flexibly adjusted. In order to fully simulate the atmospheric environment, the gas can be compressed air. The air source and the bidirectional air pump belong to mature existing technologies and will not be repeated here.

[0032] The environmental factor control component may also include a humidity controller, which may include a water source and a heat exchanger for converting water provided by the water source into water vapor or converting water vapor into water. By controlling the heat exchanger, the humidity of the test environment may be accurately controlled. The heat exchanger should be arranged inside the test box 4 and connected to the water source through a pipeline, which is a mature prior art and will not be described in detail here.

[0033] The specific structure of the environmental factor sensing component is as follows: the environmental factor sensing component includes a temperature sensor 6, a humidity sensor 7, and an air pressure sensor 8, wherein the temperature sensor 6 is used to sense the temperature in the test box 4, and the air pressure sensor 8 is used to sense the air pressure in the test box 4. Further, the temperature sensor 6, the humidity sensor 7, the air pressure sensor 8, the temperature controller 10, and the air pressure controller 12 can be electrically connected to a main controller, and the temperature sensor 6, the humidity sensor 7, the air pressure sensor 8, the temperature controller 10, and the air pressure controller 12 can be directly controlled by the main controller. The main controller can adopt an STM32 series single-chip microcomputer based on the ARM architecture, which is low in cost and has complete supporting tools, and is easy to perform high-precision control of the environmental factor control component and the environmental factor sensing component.

[0034] In order to further ensure the accuracy of the test results, a matte coating is coated on the inner wall of the test box 4, which is used to absorb stray light and avoid interference with the echo light beam. On the other hand, an insulation layer is provided on the outer wall of the test box 4, which is used to prevent the test box 4 from excessive heat exchange with the surrounding environment, thereby preventing changes in the temperature, humidity and air pressure in the test box 4, ensuring the stability of the test environment, and achieving the effect of improving the accuracy of the test results.

[0035] like Figure 2 As shown, the present invention further provides an atmospheric waveguide lidar testing method, based on the above-mentioned atmospheric waveguide lidar testing device, the method includes S1 to S4.

[0036] S1. The energy of the test beam is adjusted to the target energy level by adjusting the attenuation magnification of the laser filter 2 until the intensity of the test beam meets the weakest signal intensity when the laser radar is actually used. At the weakest signal intensity, the accuracy of the laser radar will also drop to the minimum, so that the performance of the laser radar can be tested more accurately.

[0037] S2. Use the environmental factor control component to form a test environment in the test box 4, and use the environmental factor sensing component to determine whether the test environment reaches the preset environmental conditions. More specifically, in the test environment, the temperature is set to the upper limit or lower limit of the nominal temperature measurement range of the laser radar, the humidity is set to the upper limit or lower limit of the nominal humidity measurement range of the laser radar, and the air pressure is set to the upper limit or lower limit of the nominal air pressure measurement range of the laser radar. It should be noted that the above-mentioned upper or lower limits should be used at the same time, and the upper and lower limits cannot be mixed to avoid the test results failing to accurately reflect the performance of the laser radar.

[0038] S3. Introduce the test light beam into the test box 4 using an incident mechanism.

[0039] S4. Use the emission mechanism to lead the echo light beam from the test box 4 to the receiving component of the laser radar.

[0040] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An atmospheric waveguide laser radar test device, characterized in that: It comprises a test box (4), an incident mechanism for introducing a test light beam emitted by a laser radar into the test box (4), an environment construction mechanism for forming a test environment inside the test box (4), and an emission mechanism for emitting an echo light beam from the test box (4) to the laser radar; The incident mechanism comprises a laser filter (2) and a first optical fiber (3) which are sequentially arranged along the irradiation direction of the test light beam; The environment construction mechanism comprises an environmental factor control component for forming the test environment in the test box (4) and an environmental factor sensing component for sensing the test environment; The emission mechanism comprises a third lens (11) mounted on the test box (4), a second optical fiber (13) for sending the echo light beam in the test box (4) back to the laser radar, and a fourth lens (14) for collimating the echo light beam.

2. An atmospheric waveguide laser radar test device as claimed in claim 1, characterized in that: The incident mechanism comprises a first lens (1) located in front of the laser filter (2), and the first lens (1) is used to collect the test light beam.

3. The atmospheric waveguide laser radar test device according to claim 1, characterized in that: The injection mechanism comprises a second lens (5) located at the output end of the first optical fiber (3), and the second lens (5) is used to collimate the test light beam.

4. The atmospheric waveguide laser radar test device according to claim 1, characterized in that: The environmental factor control component comprises a temperature controller (10) and an air pressure controller (12), wherein the temperature controller (10) is used to control the temperature in the test box (4), and the air pressure controller (12) is used to control the air pressure in the test box (4).

5. The atmospheric waveguide laser radar test device according to claim 4, characterized in that: The environmental factor sensing component comprises a temperature sensor (6) and an air pressure sensor (8), wherein the temperature sensor (6) is used to sense the temperature in the test box (4), and the air pressure sensor (8) is used to sense the air pressure in the test box (4).

6. The atmospheric waveguide laser radar test device according to claim 5, characterized in that: The environmental factor sensing component also includes a humidity sensor (7).

7. The atmospheric waveguide laser radar test device according to claim 1, characterized in that: The inner wall of the test box (4) is coated with a matte coating, and the outer wall of the test box (4) is provided with a heat-insulating layer.

8. The atmospheric waveguide laser radar test device according to claim 1, characterized in that: A beam collector (9) is installed in the test box (4) in the irradiation direction of the test beam.

9. An atmospheric waveguide laser radar testing method, characterized in that: Based on an atmospheric waveguide laser radar testing device as described in any one of claims 1 to 8, the method comprises the following steps: The energy of the test light beam is adjusted to a target energy level by adjusting the attenuation magnification of the laser filter (2); Using the environmental factor control component to form a test environment in the test box (4), and using the environmental factor sensing component to determine whether the test environment meets preset environmental conditions; Using the incident mechanism to introduce the test light beam into the test box (4); The emission mechanism is used to lead the echo light beam from the test box (4) to the receiving component of the laser radar.

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