An aerosol lidar calibration method, device, electronic equipment and medium

Abstract

The present disclosure relates to the technical field of meteorological detection, and in particular to an aerosol laser radar calibration method and device, electronic equipment and a medium. The method comprises: acquiring distance calibration signals of two laser radars and respectively calculating extinction coefficient profiles, if the two extinction coefficient profiles satisfy a first preset condition, outputting any one of the extinction coefficient profiles; acquiring a light power signal of a laser radar to be calibrated at a preset position, inputting the light power signal into a laser radar equation to obtain a second extinction coefficient; extracting a first extinction coefficient of the any one of the extinction coefficient profiles at the preset position, calculating an error between the first extinction coefficient and the second extinction coefficient, and judging whether the error is within a preset threshold range; if yes, outputting the laser radar equation. The above technical solution solves the problem of laser radar ratio of the laser radar equation in the prior art which needs to be assumed.

Description

Technical Field

[0001] This disclosure relates to the field of meteorological detection technology, specifically to an aerosol lidar calibration method, apparatus, electronic equipment, and medium. Background Technology

[0002] Aerosol lidar can measure the spatial distribution of atmospheric aerosols and fine particles, and its applications in meteorology, environmental protection, and other fields are becoming increasingly widespread. Therefore, calibrating aerosol lidar to obtain accurate meteorological data is becoming increasingly important. However, current technologies typically use lidar equations with assumed lidar ratios for calibration, leading to inaccurate calibration and resulting in low accuracy and large biases in the detected data. Summary of the Invention

[0003] To address the problems in related technologies, this disclosure provides an aerosol lidar calibration method, apparatus, electronic device, and medium.

[0004] In a first aspect, this disclosure provides an aerosol lidar calibration method.

[0005] Specifically, the aerosol lidar calibration method includes:

[0006] Acquire the distance calibration signals of the two opposing lidars and calculate the extinction coefficient profiles respectively. If the two extinction coefficient profiles meet the first preset condition, output any one of the extinction coefficient profiles.

[0007] The optical power signal of the lidar to be calibrated at a preset position is obtained, and the optical power signal is input into the lidar equation to solve for the second extinction coefficient. The preset position is the intersection of the laser signals emitted by the lidar to be calibrated and the two lidars.

[0008] Extract the first extinction coefficient of any extinction coefficient profile at the preset position, calculate the error between the first extinction coefficient and the second extinction coefficient, and determine whether the error is within the preset threshold range;

[0009] If so, output the lidar equation;

[0010] If not, the updated lidar equation is obtained by adjusting the lidar ratio in the lidar equation, and the updated lidar equation is output. The error between the updated second extinction coefficient calculated by the updated lidar equation and the first extinction coefficient is within the preset threshold range.

[0011] Optionally, the step of acquiring the distance calibration signals of the two opposing lidars and calculating the extinction coefficient profiles respectively, and outputting any one of the extinction coefficient profiles if the two extinction coefficient profiles satisfy a first preset condition, includes:

[0012] The two lidar units are designated as lidar A and lidar B, with lidar A located at the first end and lidar B located at the second end.

[0013] For radar A, an initial value for the extinction coefficient at the second end is set, and an initial first extinction coefficient profile is calculated based on the range calibration signal of radar A. For radar B, an initial value for the extinction coefficient at the first end is set, and an initial second extinction coefficient profile is calculated based on the range calibration signal of radar B. If the first and second extinction coefficient profiles satisfy a first preset condition, then any extinction coefficient profile is output; otherwise,

[0014] The extinction coefficient at the first end of the first extinction coefficient profile is used as the iterative value of the initial value of the extinction coefficient at the first end. The extinction coefficient at the second end of the second extinction coefficient profile is used as the iterative value of the initial value of the extinction coefficient at the second end. The steps of calculating the first extinction coefficient profile and the second extinction coefficient profile are repeated until the first extinction coefficient profile and the second extinction coefficient profile meet the first preset condition, and then any extinction coefficient profile is output.

[0015] Optionally, the first preset condition is:

[0016] Calculate the extinction coefficients of the two extinction coefficient profiles respectively;

[0017] Determine whether the error between the two extinction coefficients is within the preset threshold range.

[0018] Optionally, the initial value of the extinction coefficient can be calculated using the Collis slope method; and / or

[0019] The first extinction coefficient profile and the second extinction coefficient profile were calculated using the Klett algorithm.

[0020] Optionally, the Fernald solution method can be used to solve the lidar equation and the updated lidar equation to obtain the second extinction coefficient and the updated second extinction coefficient.

[0021] Optionally, the two lidar units are located at the same height; or

[0022] The laser beams emitted by the two lidar units are parallel; or

[0023] The angle between the laser beams emitted by the two lidars is less than or equal to 10 degrees.

[0024] Secondly, this disclosure provides an aerosol lidar calibration device.

[0025] Specifically, the aerosol lidar calibration device includes:

[0026] The light coefficient profile calculation module is configured to acquire the distance calibration signals of two opposing lidars and calculate the extinction coefficient profiles respectively. If the two extinction coefficient profiles meet the first preset condition, then any one of the extinction coefficient profiles is output.

[0027] The second extinction coefficient calculation module is configured to acquire the optical power signal of the lidar to be calibrated at a preset position, input the optical power signal into the lidar equation to solve for the second extinction coefficient, wherein the preset position is the intersection point of the laser signals emitted by the lidar to be calibrated and the two lidars.

[0028] The judgment module is configured to extract the first extinction coefficient of any extinction coefficient profile at the preset position, calculate the error between the first extinction coefficient and the second extinction coefficient, and determine whether the error is within a preset threshold range.

[0029] The output module, if configured to output the lidar equation if so, is configured to do so.

[0030] The update module is configured to, if not, obtain an updated lidar equation by adjusting the lidar ratio in the lidar equation and output the updated lidar equation, wherein the error between the updated second extinction coefficient calculated by the updated lidar equation and the first extinction coefficient is within the preset threshold range.

[0031] Optionally, the extinction coefficient profile calculation module includes:

[0032] The marking unit is configured to mark two lidars as radar A and radar B, with radar A located at the first end and radar B located at the second end;

[0033] The extinction coefficient profile output unit is configured to, for radar A, set an initial value for the extinction coefficient at the second end and calculate an initial first extinction coefficient profile based on the range calibration signal of radar A; for radar B, set an initial value for the extinction coefficient at the first end and calculate an initial second extinction coefficient profile based on the range calibration signal of radar B; if the first extinction coefficient profile and the second extinction coefficient profile satisfy a first preset condition, then output any extinction coefficient profile; otherwise,

[0034] The iteration unit is configured to take the extinction coefficient at the first end of the first extinction coefficient profile as the iteration value of the initial value of the extinction coefficient at the first end, and take the extinction coefficient at the second end of the second extinction coefficient profile as the iteration value of the initial value of the extinction coefficient at the second end, and repeat the steps of calculating the first extinction coefficient profile and the second extinction coefficient profile until the first extinction coefficient profile and the second extinction coefficient profile meet the first preset condition, and output any extinction coefficient profile.

[0035] Optionally, the first preset condition is:

[0036] Calculate the extinction coefficients of the two extinction coefficient profiles respectively;

[0037] Determine whether the error between the two extinction coefficients is within the preset threshold range.

[0038] Optionally, the initial value of the extinction coefficient can be calculated using the Collis slope method; and / or

[0039] The first extinction coefficient profile and the second extinction coefficient profile were calculated using the Klett algorithm.

[0040] Optionally, the Fernald solution method can be used to solve the lidar equation and the updated lidar equation to obtain the second extinction coefficient and the updated second extinction coefficient.

[0041] Optionally, the two lidar units are located at the same height; or

[0042] The laser beams emitted by the two lidar units are parallel; or

[0043] The angle between the laser beams emitted by the two lidars is less than or equal to 10 degrees.

[0044] Thirdly, embodiments of this disclosure provide an electronic device including a memory and a processor, wherein the memory is used to store one or more computer instructions, wherein the one or more computer instructions are executed by the processor to implement the method as described in any of the first aspects.

[0045] Fourthly, this disclosure provides a computer-readable storage medium having computer instructions stored thereon, which, when executed by a processor, implement the method as described in any of the first aspects.

[0046] According to the aerosol lidar calibration method, apparatus, electronic device, and medium provided in the embodiments of this disclosure, the method includes: acquiring distance calibration signals from two opposing lidars and calculating extinction coefficient profiles for each; if two extinction coefficient profiles satisfy a first preset condition, then outputting any one of the extinction coefficient profiles; acquiring the optical power signal of the lidar to be calibrated at a preset position, inputting the optical power signal into the lidar equation to solve for a second extinction coefficient, wherein the preset position is the intersection point of the laser signals emitted by the lidar to be calibrated and the two lidars; extracting the first extinction coefficient of the arbitrary extinction coefficient profile at the preset position, calculating the error between the first extinction coefficient and the second extinction coefficient, and determining whether the error is within a preset threshold range; if yes, then outputting the lidar equation; if no, then obtaining an updated lidar equation by adjusting the lidar ratio in the lidar equation, and outputting the updated lidar equation, wherein the error between the updated second extinction coefficient calculated by the updated lidar equation and the first extinction coefficient is within the preset threshold range. The above technical solution obtains the extinction coefficient profiles of two opposing lidars that meet the first preset condition, then obtains the second extinction coefficient of the lidar to be calibrated at a preset position, calculates the error between the second extinction coefficient and the first extinction coefficient on the extinction coefficient profile at the preset position, and finally adjusts the lidar ratio in the lidar equation according to the error, outputting a lidar equation with a definite lidar ratio, making the calibration of the lidar to be calibrated more accurate, improving the accuracy of the detection data of the lidar to be calibrated, and reducing its detection data deviation.

[0047] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0048] Other features, objects, and advantages of this disclosure will become more apparent from the following detailed description of non-limiting embodiments, taken in conjunction with the accompanying drawings. In the drawings:

[0049] Figure 1 A flowchart illustrating an aerosol lidar calibration method according to an embodiment of the present disclosure is shown.

[0050] Figure 2 The diagram illustrates an application scenario of the aerosol lidar calibration method according to an embodiment of the present disclosure.

[0051] Figure 3 The diagram illustrates the iterative process of two extinction coefficient profiles in an aerosol lidar calibration method according to an embodiment of the present disclosure.

[0052] Figure 4A structural block diagram of an aerosol lidar calibration apparatus according to an embodiment of the present disclosure is shown.

[0053] Figure 5 A structural block diagram of an electronic device according to an embodiment of the present disclosure is shown.

[0054] Figure 6 A schematic diagram of the structure of a computer system suitable for implementing the method according to embodiments of the present disclosure is shown. Detailed Implementation

[0055] In the following, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings to enable those skilled in the art to readily implement them. Furthermore, for clarity, portions unrelated to the description of exemplary embodiments have been omitted from the drawings.

[0056] In this disclosure, it should be understood that terms such as “comprising” or “having” are intended to indicate the presence of features, figures, steps, behaviors, components, parts or combinations thereof disclosed in this specification, and are not intended to exclude the possibility of the presence or addition of one or more other features, figures, steps, behaviors, components, parts or combinations thereof.

[0057] It should also be noted that, unless otherwise specified, the embodiments and features described in this disclosure can be combined with each other. This disclosure will now be described in detail with reference to the accompanying drawings and embodiments.

[0058] In this disclosure, any operation involving the acquisition of user information or user data, or the display of user information or user data to others, is an operation authorized or confirmed by the user, or actively selected by the user.

[0059] Aerosol lidar can measure the spatial distribution of atmospheric aerosols and fine particles, and its applications in meteorology, environmental protection, and other fields are becoming increasingly widespread. Therefore, calibrating aerosol lidar to obtain accurate meteorological data is becoming increasingly important. However, current technologies typically use lidar equations with assumed lidar ratios for calibration, leading to inaccurate calibration and resulting in low accuracy and large biases in the detected data.

[0060] Figure 1 A flowchart illustrating an aerosol lidar calibration method according to an embodiment of the present disclosure is shown. Figure 2 The diagram illustrates an application scenario of the aerosol lidar calibration method according to an embodiment of the present disclosure. Figure 3 The diagram illustrates the iterative process of two extinction coefficient profiles in an aerosol lidar calibration method according to an embodiment of the present disclosure.

[0061] like Figure 1 As shown, the aerosol lidar calibration method includes the following steps S101-S105:

[0062] Step S101: Obtain the distance calibration signals of the two opposing lidars and calculate the extinction coefficient profiles respectively. If the two extinction coefficient profiles meet the first preset condition, output any one of the extinction coefficient profiles.

[0063] Step S102: Obtain the optical power signal of the lidar to be calibrated at a preset position, and input the optical power signal into the lidar equation to solve for the second extinction coefficient. The preset position is the intersection of the laser signals emitted by the lidar to be calibrated and the two lidars.

[0064] Step S103: Extract the first extinction coefficient of any extinction coefficient profile at the preset position, calculate the error between the first extinction coefficient and the second extinction coefficient, and determine whether the error is within the preset threshold range;

[0065] Step S104: If yes, output the lidar equation;

[0066] Step S105: If not, then obtain an updated lidar equation by adjusting the lidar ratio in the lidar equation, and output the updated lidar equation, wherein the error between the updated second extinction coefficient calculated by the updated lidar equation and the first extinction coefficient is within the preset threshold range.

[0067] The aerosol lidar calibration method provided in this embodiment obtains the extinction coefficient profiles of two opposing lidars that meet a first preset condition, then obtains the second extinction coefficient of the lidar to be calibrated at a preset position, calculates the error between the second extinction coefficient and the first extinction coefficient on the extinction coefficient profile at the preset position, and finally adjusts the lidar ratio in the lidar equation according to the error, outputting a lidar equation with a definite lidar ratio. This makes the calibration of the lidar to be calibrated more accurate, improves the accuracy of the detection data of the lidar to be calibrated, and reduces the deviation of its detection data.

[0068] According to an embodiment of this disclosure, step S101, which involves acquiring the distance calibration signals of two opposing lidars and calculating the extinction coefficient profiles for each, and outputting any one of the extinction coefficient profiles if both extinction coefficient profiles satisfy a first preset condition, includes the following method for calculating the extinction coefficient profile:

[0069] like Figure 2As shown, the two lidars are designated as lidar A and lidar B. LiDAR A is located at the first end, and lidar B is located at the second end. LiDAR A and lidar B transmit signals relative to each other. The specific positions of lidar A and lidar B can be, for example, lidar A and lidar B are at the same height, or the laser beams emitted by lidar A and lidar B are parallel, or the angle between the laser beams emitted by lidar A and lidar B is less than or equal to 10 degrees.

[0070] For radar A, an initial value for the extinction coefficient at the second end is set, and an initial first extinction coefficient profile is calculated based on the range calibration signal of radar A. For radar B, an initial value for the extinction coefficient at the first end is set, and an initial second extinction coefficient profile is calculated based on the range calibration signal of radar B. The initial value for the extinction coefficient can be calculated using the Collis slope method; and / or the first and second extinction coefficient profiles can be calculated using the Klett algorithm.

[0071] If the first extinction coefficient profile and the second extinction coefficient profile satisfy the first preset condition, then any extinction coefficient profile is output; otherwise, the extinction coefficient at the first end of the first extinction coefficient profile is used as the iterative value of the initial value of the extinction coefficient at the first end, and the extinction coefficient at the second end of the second extinction coefficient profile is used as the iterative value of the initial value of the extinction coefficient at the second end. The steps of calculating the first extinction coefficient profile and the second extinction coefficient profile are repeated until the first extinction coefficient profile and the second extinction coefficient profile satisfy the first preset condition, and then any extinction coefficient profile is output.

[0072] The first preset condition is as follows: calculate the sum of the extinction coefficients of the two extinction coefficient profiles respectively; and determine whether the error between the two sums of extinction coefficients is within the preset threshold range. Specifically, for example, for radar A and radar B, sum the extinction coefficients in the extinction coefficient profiles of radar A and radar B respectively to obtain SumA and SumB, and then determine whether the error between SumA and SumB is within the preset threshold range. The threshold range can be set by those skilled in the art based on experience, and this disclosure does not limit it. For example, it can be 2% to 10%, preferably 5%. Then the first preset condition is: |SumA-SumB| / SumB≤5%.

[0073] According to an embodiment of this disclosure, step S102 involves acquiring the optical power signal of the lidar to be calibrated at a preset position, and inputting the optical power signal into the lidar equation to solve for the second extinction coefficient. The preset position is the intersection of the laser signals emitted by the lidar to be calibrated and the two lidars. Please refer to the following steps for further details. Figure 2Let the lidar to be calibrated be labeled as lidar C, and let the point where the laser signals emitted by lidar C intersect with those emitted by lidar A and lidar B be labeled as point Z. Obtain the optical power signal of lidar C at point Z, and input it into the lidar equation to solve for the second extinction coefficient α of lidar C at point Z. c (Z). Specifically, the second extinction coefficient can be obtained by solving the lidar equation using the Fernald method. It is understood that other algorithms can also be used to solve the lidar equation, and this disclosure does not limit this.

[0074] According to an embodiment of this disclosure, step S103, which involves extracting the first extinction coefficient of any extinction coefficient profile at a preset position, calculating the error between the first extinction coefficient and the second extinction coefficient, and determining whether the error is within a preset threshold range, for example, involves outputting the extinction coefficient profile of radar A and extracting the extinction coefficient α of radar A at point Z. A (Z), the extinction coefficient of radar C at point Z is α. c (Z), then the formula for calculating the error σ between radar A and radar C at point Z is: σ=|α A (Z)-α c (Z)| / α A (Z). The preset threshold range of the error σ can be set by those skilled in the art based on experience, and this disclosure does not limit it. For example, it can be 2% to 10%, preferably 5%. Accordingly, determining whether the error is within the preset threshold range is equivalent to determining whether σ satisfies the condition: σ < 5%.

[0075] If so, then continue with step S104 of this disclosure, that is, output the lidar equation to complete the calibration.

[0076] If not, proceed to step S105 of this disclosure, i.e., obtain an updated lidar equation by adjusting the lidar ratio in the lidar equation, and output the updated lidar equation, wherein the error between the updated second extinction coefficient calculated by the updated lidar equation and the first extinction coefficient is within the preset threshold range. The updated second extinction coefficient can be obtained by solving the updated lidar equation using the Fernald method. It is understood that other algorithms can also be used to solve the lidar equation, and this disclosure does not impose any limitations on this.

[0077] Please continue to refer to Figure 2 and Figure 3 The specific steps of the aerosol lidar calibration method disclosed herein include:

[0078] 1. Radar A and Radar B emit lasers towards each other, with the directions of their emitted lasers being parallel or the angle between their emitted laser beams not exceeding 10 degrees.

[0079] 2. The range calibration signals detected by radar A and radar B are denoted as RCS respectively. A (Z) and RCS B (Z).

[0080] 3.1 First step: For radar A and radar B, use the slope method to adjust the range calibration signal RCS. A (Z) and RCS B (Z) Calculate the slope to obtain initial extinction coefficient values ​​A0 and B0, and use the Klett algorithm to obtain the extinction coefficient profile. The extinction coefficient value near end A of the extinction coefficient profile of radar A is B1. The extinction coefficient value near end B of the extinction coefficient profile of radar B is A1. Sum the extinction coefficients in the extinction coefficient profiles of radar A and radar B respectively to obtain SumA and SumB. If |SumA-SumB| / SumB>5%, continue to the next calculation; otherwise, output the extinction coefficient profile α of radar A. A .

[0081] 3.2 Second Step: For radars A and B, using extinction coefficients A1 and B1 as initial values, the Klett algorithm is used to obtain the iterative extinction coefficient profiles. The extinction coefficient value near end A of the extinction coefficient profile of radar A is B2. The extinction coefficient value near end B of the extinction coefficient profile of radar B is A2. The extinction coefficients in the extinction coefficient profiles of radars A and B are then summed to obtain SumA and SumB respectively. If |SumA-SumB| / SumB>5%, the next calculation continues; otherwise, the extinction coefficient profile α of radar A is output. A .

[0082] 3.3 The nth iteration: For radar A and radar B, using extinction coefficients An⁻¹ and Bⁿ⁻¹ as initial values, the extinction coefficient profiles are obtained using the Klett algorithm. The extinction coefficient value near the A end of the extinction coefficient profile of radar A is Bⁿ. The extinction coefficient value near the B end of the extinction coefficient profile of radar B is An. The extinction coefficients in the extinction coefficient profiles of radar A and radar B are summed to obtain SumA and SumB respectively. It is calculated that |SumA-SumB| / SumB < 5%, and the extinction coefficient profile α of radar A is output. A .

[0083] 4. When the laser beam of the radar C to be calibrated passes between radar A and radar B, the optical power signal is measured at the intersection (Z) in the vertical or non-vertical direction. The extinction coefficient α is obtained by solving the lidar equation using the Fernald method. c (Z).

[0084] 5. Extract the extinction coefficient α at point Z from the extinction coefficient profile of radar A. A(Z), calculate its extinction coefficient α at point Z, which is the same as that of the radar C to be calibrated. c The error between (Z) is calculated using the following formula:

[0085] σ=|α A (Z)-α c (Z)| / αA(Z)

[0086] 6. If the calculated σ < 0.05, then the calibration of radar C is completed and the lidar equation is output; if σ ≥ 0.05, then the lidar ratio in the lidar equation of radar C is adjusted to obtain the updated lidar equation, so that σ < 0.05, then the calibration of radar C is completed and the updated lidar equation is output.

[0087] Figure 4 A structural block diagram of an aerosol lidar calibration apparatus according to an embodiment of the present disclosure is shown. This apparatus can be implemented as part or all of an electronic device through software, hardware, or a combination of both.

[0088] like Figure 4 As shown, the aerosol lidar calibration device 400 includes:

[0089] The extinction coefficient profile calculation module 410 is configured to acquire the distance calibration signals of two opposing lidars and calculate the extinction coefficient profiles respectively. If the two extinction coefficient profiles meet the first preset condition, then any one of the extinction coefficient profiles is output.

[0090] The second extinction coefficient calculation module 420 is configured to acquire the optical power signal of the lidar to be calibrated at a preset position, input the optical power signal into the lidar equation to solve for the second extinction coefficient, wherein the preset position is the intersection point of the laser signals emitted by the lidar to be calibrated and the two lidars.

[0091] The judgment module 430 is configured to extract the first extinction coefficient of any extinction coefficient profile at the preset position, calculate the error between the first extinction coefficient and the second extinction coefficient, and determine whether the error is within a preset threshold range.

[0092] Output module 440 is configured to output the lidar equation if the condition is met.

[0093] The update module 450 is configured to, if not, obtain an updated lidar equation by adjusting the lidar ratio in the lidar equation and output the updated lidar equation, wherein the error between the updated second extinction coefficient calculated by the updated lidar equation and the first extinction coefficient is within the preset threshold range.

[0094] The aerosol lidar calibration device provided in this embodiment obtains the extinction coefficient profiles of two opposing lidars that meet a first preset condition, then obtains the second extinction coefficient of the lidar to be calibrated at a preset position, calculates the error between the second extinction coefficient and the first extinction coefficient on the extinction coefficient profile at the preset position, and finally adjusts the lidar ratio in the lidar equation according to the error, outputting a lidar equation with a definite lidar ratio. This makes the calibration of the lidar to be calibrated more accurate, improves the accuracy of the detection data of the lidar to be calibrated, and reduces the deviation of its detection data.

[0095] According to an embodiment of this disclosure, the extinction coefficient profile calculation module 410 includes:

[0096] The marking unit is configured to mark two lidars as radar A and radar B, with radar A located at the first end and radar B located at the second end;

[0097] The extinction coefficient profile output unit is configured to, for radar A, set an initial value for the extinction coefficient at the second end and calculate an initial first extinction coefficient profile based on the range calibration signal of radar A; for radar B, set an initial value for the extinction coefficient at the first end and calculate an initial second extinction coefficient profile based on the range calibration signal of radar B; if the first extinction coefficient profile and the second extinction coefficient profile satisfy a first preset condition, then output any extinction coefficient profile; otherwise,

[0098] The iteration unit is configured to take the extinction coefficient at the first end of the first extinction coefficient profile as the iteration value of the initial value of the extinction coefficient at the first end, and take the extinction coefficient at the second end of the second extinction coefficient profile as the iteration value of the initial value of the extinction coefficient at the second end, and repeat the steps of calculating the first extinction coefficient profile and the second extinction coefficient profile until the first extinction coefficient profile and the second extinction coefficient profile meet the first preset condition, and output any extinction coefficient profile.

[0099] According to an embodiment of this disclosure, the first preset condition is:

[0100] Calculate the extinction coefficients of the two extinction coefficient profiles respectively;

[0101] Determine whether the error between the two extinction coefficients is within the preset threshold range.

[0102] According to embodiments of this disclosure, the initial value of the extinction coefficient is calculated using the Collis slope method; and / or

[0103] The first extinction coefficient profile and the second extinction coefficient profile were calculated using the Klett algorithm.

[0104] According to embodiments of this disclosure, the lidar equation and the updated lidar equation are solved using the Fernald solution method to obtain the second extinction coefficient and the updated second extinction coefficient.

[0105] According to embodiments of this disclosure, the two lidar units are located at the same height; or

[0106] The laser beams emitted by the two lidar units are parallel; or

[0107] The angle between the laser beams emitted by the two lidars is less than or equal to 10 degrees.

[0108] This disclosure also discloses an electronic device, Figure 5 A structural block diagram of an electronic device according to an embodiment of the present disclosure is shown.

[0109] like Figure 5 As shown, the electronic device includes a memory and a processor, wherein the memory is used to store one or more computer instructions, wherein the one or more computer instructions are executed by the processor to implement the following method steps:

[0110] Acquire the distance calibration signals of the two opposing lidars and calculate the extinction coefficient profiles respectively. If the two extinction coefficient profiles meet the first preset condition, output any one of the extinction coefficient profiles.

[0111] The optical power signal of the lidar to be calibrated at a preset position is obtained, and the optical power signal is input into the lidar equation to solve for the second extinction coefficient. The preset position is the intersection of the laser signals emitted by the lidar to be calibrated and the two lidars.

[0112] Extract the first extinction coefficient of any extinction coefficient profile at the preset position, calculate the error between the first extinction coefficient and the second extinction coefficient, and determine whether the error is within the preset threshold range;

[0113] If so, output the lidar equation;

[0114] If not, the updated lidar equation is obtained by adjusting the lidar ratio in the lidar equation, and the updated lidar equation is output. The error between the updated second extinction coefficient calculated by the updated lidar equation and the first extinction coefficient is within the preset threshold range.

[0115] The technical solution provided in this disclosure obtains the extinction coefficient profiles of two opposing lidars that meet the first preset condition, then obtains the second extinction coefficient of the lidar to be calibrated at a preset position, calculates the error between the second extinction coefficient and the first extinction coefficient on the extinction coefficient profile at the preset position, and finally adjusts the lidar ratio in the lidar equation according to the error, outputting a lidar equation with a definite lidar ratio. This makes the calibration of the lidar to be calibrated more accurate, improves the accuracy of the detection data of the lidar to be calibrated, and reduces the deviation of its detection data.

[0116] According to embodiments of this disclosure, the step of acquiring the distance calibration signals of two opposing lidars and calculating extinction coefficient profiles for each, and outputting any one of the extinction coefficient profiles if the two extinction coefficient profiles satisfy a first preset condition, includes:

[0117] The two lidar units are designated as lidar A and lidar B, with lidar A located at the first end and lidar B located at the second end.

[0118] For radar A, an initial value for the extinction coefficient at the second end is set, and an initial first extinction coefficient profile is calculated based on the range calibration signal of radar A. For radar B, an initial value for the extinction coefficient at the first end is set, and an initial second extinction coefficient profile is calculated based on the range calibration signal of radar B. If the first and second extinction coefficient profiles satisfy a first preset condition, then any extinction coefficient profile is output; otherwise,

[0119] The extinction coefficient at the first end of the first extinction coefficient profile is used as the iterative value of the initial value of the extinction coefficient at the first end. The extinction coefficient at the second end of the second extinction coefficient profile is used as the iterative value of the initial value of the extinction coefficient at the second end. The steps of calculating the first extinction coefficient profile and the second extinction coefficient profile are repeated until the first extinction coefficient profile and the second extinction coefficient profile meet the first preset condition, and then any extinction coefficient profile is output.

[0120] According to an embodiment of this disclosure, the first preset condition is:

[0121] Calculate the sum of the extinction coefficients for the two extinction coefficient profiles respectively; determine whether the error between the two sums of extinction coefficients is within the preset threshold range.

[0122] According to embodiments of this disclosure, the initial value of the extinction coefficient is calculated using the Collis slope method; and / or

[0123] The first extinction coefficient profile and the second extinction coefficient profile were calculated using the Klett algorithm.

[0124] According to embodiments of this disclosure, the lidar equation and the updated lidar equation are solved using the Fernald solution method to obtain the second extinction coefficient and the updated second extinction coefficient.

[0125] According to embodiments of this disclosure, the two lidar units are located at the same height; or

[0126] The laser beams emitted by the two lidar units are parallel; or

[0127] The angle between the laser beams emitted by the two lidars is less than or equal to 10 degrees.

[0128] Figure 6 A schematic diagram of the structure of a computer system suitable for implementing the method according to embodiments of the present disclosure is shown.

[0129] like Figure 6 As shown, the computer system includes a processing unit that can execute various methods described above based on a program stored in a read-only memory (ROM) or a program loaded from a storage portion into a random access memory (RAM). The RAM also stores various programs and data required for the operation of the computer system. The processing unit, ROM, and RAM are interconnected via a bus. Input / output (I / O) interfaces are also connected to the bus.

[0130] The following components are connected to the I / O interface: input sections including keyboards, mice, etc.; output sections including cathode ray tubes (CRTs), liquid crystal displays (LCDs), and speakers; storage sections including hard disks, etc.; and communication sections including network interface cards such as LAN cards and modems. The communication section performs communication processes via a network such as the Internet. Drives are also connected to the I / O interface as needed. Removable media, such as disks, optical disks, magneto-optical disks, semiconductor memories, etc., are installed on the drive as needed so that computer programs read from them can be installed into the storage section as needed. The processing unit can be implemented as a CPU, GPU, TPU, FPGA, NPU, etc.

[0131] In particular, according to embodiments of this disclosure, the methods described above can be implemented as computer software programs. For example, embodiments of this disclosure include a computer program product comprising a computer program tangibly embodied on a machine-readable medium, the computer program containing program code for performing the methods described above. In such embodiments, the computer program can be downloaded and installed from a network via a communication component, and / or installed from a removable medium.

[0132] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0133] The units or modules described in the embodiments of this disclosure can be implemented in software or programmable hardware. The described units or modules can also be located in a processor, and the names of these units or modules do not necessarily constitute a limitation on the unit or module itself.

[0134] In another aspect, this disclosure also provides a computer-readable storage medium, which may be a computer-readable storage medium included in the electronic device or computer system described above; or it may be a standalone computer-readable storage medium not assembled into a device. The computer-readable storage medium stores one or more programs, which are used by one or more processors to perform the methods described in this disclosure.

[0135] The above description is merely a preferred embodiment of this disclosure and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this disclosure is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features disclosed in this disclosure that have similar functions.

Claims

1. A method for calibrating an aerosol lidar, characterized in that, include: The distance calibration signals of two opposing lidars are acquired and the extinction coefficient profiles are calculated respectively. If the two extinction coefficient profiles satisfy a first preset condition, any one of the extinction coefficient profiles is output. The first preset condition is: calculate the sum of the extinction coefficients of the two extinction coefficient profiles respectively; and determine whether the error between the sums of the two extinction coefficients is within a preset threshold range. The optical power signal of the lidar to be calibrated at a preset position is obtained, and the optical power signal is input into the lidar equation to solve for the second extinction coefficient. The preset position is the intersection of the laser signals emitted by the lidar to be calibrated and the two lidars. Extract the first extinction coefficient of any extinction coefficient profile at the preset position, calculate the error between the first extinction coefficient and the second extinction coefficient, and determine whether the error is within the preset threshold range; If so, output the lidar equation; If not, the updated lidar equation is obtained by adjusting the lidar ratio in the lidar equation, and the updated lidar equation is output. The error between the updated second extinction coefficient calculated by the updated lidar equation and the first extinction coefficient is within the preset threshold range.

2. The calibration method according to claim 1, characterized in that, The process involves acquiring the distance calibration signals from two opposing lidars and calculating their extinction coefficient profiles. If both extinction coefficient profiles satisfy a first preset condition, then any one of the extinction coefficient profiles is output, including: The two lidar units are designated as lidar A and lidar B, with lidar A located at the first end and lidar B located at the second end. For radar A, an initial value for the extinction coefficient at the second end is set, and an initial first extinction coefficient profile is calculated based on the range calibration signal of radar A. For radar B, an initial value for the extinction coefficient at the first end is set, and an initial second extinction coefficient profile is calculated based on the range calibration signal of radar B. If the first and second extinction coefficient profiles satisfy a first preset condition, then any extinction coefficient profile is output; otherwise, The extinction coefficient at the first end of the first extinction coefficient profile is used as the iterative value of the initial value of the extinction coefficient at the first end. The extinction coefficient at the second end of the second extinction coefficient profile is used as the iterative value of the initial value of the extinction coefficient at the second end. The steps of calculating the first extinction coefficient profile and the second extinction coefficient profile are repeated until the first extinction coefficient profile and the second extinction coefficient profile meet the first preset condition, and then any extinction coefficient profile is output.

3. The calibration method according to claim 2, characterized in that, The initial value of the extinction coefficient was calculated using the Collis slope method; and / or The first extinction coefficient profile and the second extinction coefficient profile were calculated using the Klett algorithm.

4. The calibration method according to claim 1, characterized in that, The Fernald solution method is used to solve the lidar equation and the updated lidar equation to obtain the second extinction coefficient and the updated second extinction coefficient.

5. The calibration method according to claim 1, characterized in that, The two lidar units are located at the same height; or The laser beams emitted by the two lidars are parallel.

6. The calibration method according to claim 1, characterized in that, The angle between the laser beams emitted by the two lidars is less than or equal to 10 degrees.

7. An aerosol lidar calibration device, characterized in that, include: The extinction coefficient profile calculation module is configured to acquire the distance calibration signals of two opposing lidars and calculate the extinction coefficient profiles respectively. If the two extinction coefficient profiles meet a first preset condition, then any one of the extinction coefficient profiles is output. The first preset condition is: to calculate the sum of the extinction coefficients of the two extinction coefficient profiles respectively; and to determine whether the error between the sums of the two extinction coefficients is within a preset threshold range. The second extinction coefficient calculation module is configured to acquire the optical power signal of the lidar to be calibrated at a preset position, input the optical power signal into the lidar equation to solve for the second extinction coefficient, wherein the preset position is the intersection point of the laser signals emitted by the lidar to be calibrated and the two lidars. The judgment module is configured to extract the first extinction coefficient of any extinction coefficient profile at the preset position, calculate the error between the first extinction coefficient and the second extinction coefficient, and determine whether the error is within a preset threshold range. The output module, if configured to output the lidar equation if so, is configured to do so. The update module is configured to, if not, obtain an updated lidar equation by adjusting the lidar ratio in the lidar equation and output the updated lidar equation, wherein the error between the updated second extinction coefficient calculated by the updated lidar equation and the first extinction coefficient is within the preset threshold range.

8. The calibration device according to claim 7, characterized in that, The extinction coefficient profile calculation module includes: The marking unit is configured to mark two lidars as radar A and radar B, with radar A located at the first end and radar B located at the second end; The extinction coefficient profile output unit is configured to, for radar A, set an initial value for the extinction coefficient at the second end and calculate an initial first extinction coefficient profile based on the range calibration signal of radar A; for radar B, set an initial value for the extinction coefficient at the first end and calculate an initial second extinction coefficient profile based on the range calibration signal of radar B; if the first extinction coefficient profile and the second extinction coefficient profile satisfy a first preset condition, then output any extinction coefficient profile; otherwise, The iteration unit is configured to take the extinction coefficient at the first end of the first extinction coefficient profile as the iteration value of the initial value of the extinction coefficient at the first end, and take the extinction coefficient at the second end of the second extinction coefficient profile as the iteration value of the initial value of the extinction coefficient at the second end, and repeat the steps of calculating the first extinction coefficient profile and the second extinction coefficient profile until the first extinction coefficient profile and the second extinction coefficient profile meet the first preset condition, and output any extinction coefficient profile.

9. An electronic device, characterized in that, The method includes a memory and a processor; wherein the memory is used to store one or more computer instructions, wherein the one or more computer instructions are executed by the processor to implement the steps of the method according to any one of claims 1-6.

10. A computer-readable storage medium storing computer instructions thereon, characterized in that, When executed by a processor, the computer instructions implement the steps of the method described in any one of claims 1-6.

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