Atmospheric detection laser radar cooperative control device and method based on Ethernet

Abstract

An Ethernet-based atmospheric detection laser radar cooperative control device disclosed by the present invention comprises a master control module, the master control module is connected with an atomic clock, an external network interface module and a switch, and the switch is communicated with each Ethernet control module through the Ethernet. The three-frequency switching device, the variable pulse laser, the program control chopper and the photon counting acquisition card are connected and are respectively connected with the corresponding Ethernet control modules through the corresponding waveform generators, and the day and night switching device and the data transmission computer are respectively connected with the corresponding Ethernet control modules. The invention further discloses an atmosphere detection laser radar cooperative control method based on the Ethernet. The master control module is used for enabling clocks of the Ethernet control modules to be synchronized, and the corresponding working modules drive time sequences of control waveforms to be synchronized or modified in real time. The method is compatible with automatic and intelligent control of equipment, the time sequence waveform driving capacity is high, the equipment is simplified and integrated, and flexible deployment is easier.

Description

Technical Field

[0001] This invention relates to the field of automatic timing control of atmospheric sounding lidar, and more particularly to an Ethernet-based collaborative control device for atmospheric sounding lidar, and also to an Ethernet-based collaborative control method for atmospheric sounding lidar. Background Technology

[0002] Atmospheric sounding lidar obtains information such as atmospheric wind field, temperature, and density by interacting with the atmosphere using pulsed lasers of specific wavelengths. The entire operation requires strict timing control, including the synchronization of multiple timing sequences. First, the pulsed laser emission sequence, the echo chopping sequence, and the photon counting and acquisition card detection sequence must be synchronized. Second, to achieve simultaneous measurement of wind field and temperature, the 589nm seed laser needs to be switched between three frequencies, and the timing of these three frequency switching controls also needs to be synchronized. Atmospheric sounding lidar also requires timed switching between day and night operating modes, and the raw atmospheric sounding data needs to be sent to the user terminal at regular intervals.

[0003] To achieve timing synchronization, a common method is to provide timing signals to each device through a signal source. Signal sources can be internal or external. Internal signal sources mainly rely on signal generators, while external signal sources include GNSS signals (see patent CN202110672320.1 Synchronous Transmit and Receive Control of LiDAR Based on GNSS Signals). While these methods are feasible, they have the following problems: Firstly, the signal source is only connected to each device via RF cables, which only enables the transmission of analog signals between devices and does not achieve information interconnection between devices, which is not conducive to the automated and intelligent control of the equipment. Multiple devices are connected through a large number of RF cables; the RF cables for timing control alone for ground-based lidar can reach hundreds of meters in length, increasing wiring complexity and limiting the integration of atmospheric sounding lidar. GNSS timing synchronization is a wireless signal transmission, which is easily affected by weather and other signal interference, making it difficult to guarantee long-term reliable operation.

[0004] Secondly, using radio frequency signals as timing synchronization signals has the problem of insufficient driving capability due to signal attenuation during transmission or trigger failure caused by other interference. Furthermore, the system cannot record when a failure occurs, which in turn affects data inversion.

[0005] Furthermore, setting the timing sequence through internal and external signal sources is not flexible enough. However, from the perspective of the collaborative operation of atmospheric sounding lidar, to obtain better inversion results, the control timing needs to be adjusted synchronously based on the detection results. Additionally, current radio frequency signal timing synchronization cannot be integrated with the day / night switching device and data transmission computer into a single timing set. The day / night switching time needs to be determined based on the sunrise time in different locations, and the data transmission time also needs to be adjusted according to user requirements. Therefore, the current fixed timing control method restricts further improvement of the performance of atmospheric sounding lidar.

[0006] For the reasons mentioned above, there is an urgent need in the field of atmospheric detection lidar timing control technology for a convenient, reliable, and intelligent collaborative control device and method. Summary of the Invention

[0007] The purpose of this invention is to address the problems existing in the prior art by proposing an Ethernet-based atmospheric sounding lidar cooperative control device and an Ethernet-based atmospheric sounding lidar cooperative control method.

[0008] The above-mentioned objective of the present invention is achieved through the following technical solution: A collaborative control device for atmospheric sounding lidar based on Ethernet includes a central control module, which is connected to an atomic clock, an external network interface module, and a switch. The switch is connected to various Ethernet control modules via Ethernet. The Ethernet control modules include a first Ethernet control module, a second Ethernet control module, a third Ethernet control module, a fourth Ethernet control module, a fifth Ethernet control module, and a sixth Ethernet control module. Specifically, the first Ethernet control module is connected to a three-frequency switching device via a first waveform generator; the second Ethernet control module is connected to a variable pulse laser via a second waveform generator; the third Ethernet control module is connected to a programmable chopper via a third waveform generator; the fourth Ethernet control module is connected to a photon counting and acquisition card via a fourth waveform generator; the fifth Ethernet control module is connected to a day / night switching device; and the sixth Ethernet control module is connected to a data transmission computer.

[0009] A collaborative control method for an Ethernet-based atmospheric sounding lidar, utilizing the Ethernet-based atmospheric sounding lidar collaborative control device described above, includes the following steps: Step 1: Build an Ethernet-based atmospheric sounding lidar collaborative control device. The main control module can be connected to the Internet via an external network interface module or connected to an atomic clock. The first Ethernet control module, the second Ethernet control module, the third Ethernet control module, and the fourth Ethernet control module all store the waveforms of the corresponding waveform generator drive signals; Step 2: After the atmospheric detection lidar collaborative control device has been powered on and warmed up, the main control module sends a time synchronization start command to each Ethernet control module via Ethernet through the switch. After receiving the time synchronization start command, each Ethernet control module sends a time synchronization request to the main control module. After receiving the time synchronization request, the main control module records the timestamp t1 of receiving the time synchronization request and includes the timestamp t1 of receiving the time synchronization request in its reply. After receiving the reply, each Ethernet control module records the timestamp t2 of receiving the reply from the main control module. Each Ethernet control module calculates the network delay between the corresponding Ethernet control module and the main control module and the current time of the main control module through the corresponding timestamp t1 and timestamp t2, and then adjusts the corresponding clock of the Ethernet control module to synchronize with the clock of the main control module. Step 3: After completing the aforementioned steps, each Ethernet control module obtains the same reference time T0; Based on the reference time T0, the first Ethernet control module, the second Ethernet control module, the third Ethernet control module and the fourth Ethernet control module drive their respective waveform generators to generate corresponding working module drive control waveforms, and each working module drive control waveform is sent to the corresponding working module so that the corresponding working module starts to work synchronously according to the corresponding working module drive control waveform. Among them, the working module corresponding to the first Ethernet control module is a three-frequency switching device, the working module corresponding to the second Ethernet control module is a variable pulse laser, the working module corresponding to the third Ethernet control module is a programmable chopper, and the working module corresponding to the fourth Ethernet control module is a photon counting acquisition card. Step 4: During the observation process, based on changes in the detection environment and the quality of the echo signal, the master control module sends timing modification commands to the corresponding Ethernet control module. Step 5: After the observation is completed, the raw echo data collected by the photon counting acquisition card is uploaded to the data transmission computer (20) for local data inversion, so as to obtain the atmospheric density, wind field and temperature above the observation area; or the raw echo photon count is transmitted to the remote computer via the external network through the data transmission computer, and the data inversion is performed on the remote computer to obtain the atmospheric density, wind field and temperature above the observation area.

[0010] As described above, step 4 specifically includes the following process: During the observation process, if the number of original echo photons in the original echo count acquired by the photon counting acquisition card decreases, the main control module sends a timing modification command to the second Ethernet control module, the third Ethernet control module, and the fourth Ethernet control module to increase the frequency of the timing of the variable pulse laser's working module drive control waveform. At the same time, the frequency of the timing of the programmable chopper's working module drive control waveform and the frequency of the photon counting acquisition card's working module drive control waveform are also synchronized accordingly.

[0011] As mentioned above, step 4 also includes the following process: If the low-altitude signal is found to exceed the dynamic range of the photon counting acquisition card during the observation process, the main control module sends a timing modification command to the third Ethernet control module, which adjusts the working module of the programmable chopper to drive the control waveform and modify the on-time of the programmable chopper. Calculate the change in the on-time of the programmable chopper using the following formula. : , in, This refers to the altitude value corresponding to the low-altitude signal that needs to be cut off. It is the speed of light.

[0012] As mentioned above, step 4 also includes the following process: If the timing period of the working module drive control waveform of the three-frequency switching device is required, the main control module sends a timing modification command to the first Ethernet control module to modify the timing period of the working module drive control waveform. At the same time, the main control module sends a timing modification command to the fourth Ethernet control module to synchronize the timing of the Tag signal in the timing of the working module drive control waveform of the photon counting acquisition card with the timing of the working module drive control waveform of the three-frequency switching device.

[0013] As mentioned above, step 4 also includes the following process: If the local sunrise time changes during the observation period, the main control module first queries the day-night switching time via the Internet or the day-night switching time is manually input into the main control module. Then, the main control module sends a timing modification command to the fifth Ethernet control module to modify the day-night switching time of the day-night switching device.

[0014] As mentioned above, step 4 also includes the following process: If, during the observation period, the data receiver requests a change in the time at which data is transmitted to the data transmission computer, the main control module sends a timing modification command to the sixth Ethernet control module, causing the sixth Ethernet control module to start data transmission according to the new time setting.

[0015] As described above, the data transmission computer receives remote instructions and forwards them to the central control module, which then sends timing modification instructions to the corresponding Ethernet control module.

[0016] Compared with the prior art, the present invention has the following advantages: This invention achieves multi-time sequence control of atmospheric sounding lidar via Ethernet, and is compatible with automated and intelligent equipment control. It does not rely on traditional analog signal connections, resulting in higher reliability and strong timing waveform driving capability. This simplifies and integrates the equipment, making it easier to deploy flexibly and dynamically. Simultaneously, it solves the difficulty of automatically adjusting the control timing of conventional atmospheric sounding lidar. This invention uses Ethernet commands to uniformly manage the timing of each component, achieving full digitalization of timing coordination and effectively improving the quality of atmospheric sounding lidar detection data. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the device of the present invention; Figure 2 Overall timing diagram; where, the pulsed laser timing is the timing of the driving control waveform of the working module of the variable pulsed laser; the acquisition card trigger timing is the driving waveform timing in the timing of the driving control waveform of the working module of the photon counting acquisition card; the chopper trigger timing is the timing of the driving control waveform of the working module of the programmable chopper; the three-frequency timing F+, three-frequency timing F0, and three-frequency timing F- are the timing of the driving control waveform of the working module of the three-frequency switching device; the tag signal is the three-frequency acquisition card marker bit, which belongs to the control waveform timing in the timing of the driving control waveform of the working module of the photon counting acquisition card, and changes with the changes of the three-frequency timing F+, three-frequency timing F0, and three-frequency timing F-. Figure 3 Timing diagram for coordinated adjustment of variable timing pulse laser, photon counting acquisition card, and chopper transceiver; Figure 4 This is a timing diagram for the coordinated adjustment of three-frequency switching transmit and receive signals; Among them, 1-Atomic clock, 2-Master control module, 3-External network interface module, 4-Switch, 5-First Ethernet control module, 6-Second Ethernet control module, 7-Third Ethernet control module, 8-Fourth Ethernet control module, 9-Fifth Ethernet control module, 10-Sixth Ethernet control module, 11-First waveform generator, 12-Second waveform generator, 13-Third waveform generator, 14-Fourth waveform generator, 15-Three-frequency switching device, 16-Variable pulse laser, 17-Programmable chopper, 18-Photon counting and acquisition card, 19-Day / night switching device, 20-Data transmission computer. Detailed Implementation

[0018] To facilitate understanding and implementation of the present invention by those skilled in the art, the present invention will be further described in detail below with reference to implementation examples. It should be understood that the implementation examples described herein are for illustration and explanation only and are not intended to limit the present invention.

[0019] Example 1 An Ethernet-based atmospheric sounding lidar cooperative control device, such as Figure 1 As shown, the system includes a central control module 2, which is connected to an atomic clock 1, an external network interface module 3, and a switch 4. The switch 4 is connected to various Ethernet control modules via Ethernet. The Ethernet control modules include a first Ethernet control module 5, a second Ethernet control module 6, a third Ethernet control module 7, a fourth Ethernet control module 8, a fifth Ethernet control module 9, and a sixth Ethernet control module 10. Specifically, the first Ethernet control module 5 is connected to a three-frequency switching device 15 via a first waveform generator 11; the second Ethernet control module 6 is connected to a variable pulse laser 16 via a second waveform generator 12; the third Ethernet control module 7 is connected to a programmable chopper 17 via a third waveform generator 13; the fourth Ethernet control module 8 is connected to a photon counting acquisition card 18 via a fourth waveform generator 14; the fifth Ethernet control module 9 is connected to a day / night switching device 19; and the sixth Ethernet control module 10 is connected to a data transmission computer 20.

[0020] The three-frequency switching device 15, variable pulse laser 16, programmable chopper 17, photon counting and acquisition card 18, day-night switching device 19, and data transmission computer 20 are all working modules; among them, the three-frequency switching device 15 and variable pulse laser 16 belong to the laser emitting unit, the programmable chopper 17, photon counting and acquisition card 18, and day-night switching device 19 belong to the optical receiving unit, and the data transmission computer 20 belongs to the data transmission unit.

[0021] This invention modifies the interfaces of the three-frequency switching device 15, the variable pulse laser 16, the programmable chopper 17, the photon counting and acquisition card 18, the day-night switching device 19, and the data transmission computer 20, and adds corresponding Ethernet control modules and waveform generators. The Ethernet control modules can synchronize the current clock, and the first Ethernet control module 5, the second Ethernet control module 6, the third Ethernet control module 7, and the fourth Ethernet control module 8 include waveform drivers to generate real-time waveform generator drive signals, thereby driving the corresponding waveform generators to generate the corresponding working module drive control waveforms (the working module corresponding to the first Ethernet control module 5 is the three-frequency switching device 15, the working module corresponding to the second Ethernet control module 6 is the variable pulse laser 16, the working module corresponding to the third Ethernet control module 7 is the programmable chopper 17, and the working module corresponding to the fourth Ethernet control module 8 is the photon counting and acquisition card 18). Meanwhile, each Ethernet control module is connected to the main control module 2 via Ethernet. The main control module 2 is connected to the high-precision atomic clock 1 or to the external Internet via the external network interface module 3. The data transmission computer 20 transmits external control signals via Ethernet according to the control algorithm, thereby making unified and precise adjustments to the timing of the laser emitting unit and the optical receiving unit.

[0022] During operation of the device of this invention, the variable pulse laser 16 emits pulsed laser according to the timing of the corresponding working module drive control waveform. Simultaneously, the variable pulse laser 16 receives the signal timing waveform output from the three-frequency switching device 15 and performs frequency switching. The echo light signal is first partially cut off by the programmable chopper 17, and then the photon counting acquisition card 18 collects the data. The acquisition card trigger timing in the working module drive control waveform of the photon counting acquisition card 18 is synchronized with the timing of the working module drive control waveform of the variable pulse laser 16. The timing of the acquisition card marker bit (i.e., the timing of the tag signal) in the working module drive control waveform of the photon counting acquisition card 18 is synchronized with the signal timing output by the three-frequency switching device 15. Simultaneously, the photon counting acquisition card 18 transmits the collected raw echo data (including a series of raw echo photon counts) to the main control module 2 via Ethernet.

[0023] The day / night switching device 19 performs day / night switching according to the time command sent by the master control module 2; in addition, the master control module 2 sends a command to the sixth Ethernet control module 10 according to the preset time point, so that the master control module 2 uploads the saved raw echo data to the data transmission computer 20, and transmits it to the user-specified location through the data transmission computer 20.

[0024] Furthermore, depending on the specific needs of different scenarios, when it is necessary to adjust the timing of the driving control waveforms of the aforementioned working modules as a whole, the main control module 2 adjusts the driving control waveforms of the corresponding working modules through the corresponding Ethernet control module. If remote adjustment is required, the remote computer sends remote instructions to the data transmission computer 20 via Ethernet, and then the data transmission computer 20 sends relevant control signals to the main control module 2. Finally, the main control module 2 adjusts the timing of the driving control waveforms of the corresponding working modules through the corresponding Ethernet control module. See Example 2 for the specific process.

[0025] Example 2 A collaborative control method for atmospheric sounding lidar based on Ethernet, utilizing the collaborative control device for atmospheric sounding lidar based on Ethernet described in Example 1, operates as follows: Step 1: Build the Ethernet-based atmospheric detection lidar collaborative control device described in Example 1. The main control module 2 can be connected to the Internet through the external network interface module 3, so as to use Internet time as the time reference; or the main control module 2 can be connected to the atomic clock 1, so as to use the local atomic clock 1 as the time reference. The first Ethernet control module 5, the second Ethernet control module 6, the third Ethernet control module 7, and the fourth Ethernet control module 8 all pre-store the waveforms of the corresponding waveform generator drive signals.

[0026] The aforementioned master control module 2 prioritizes using internet time as the time base. If internet access is not permitted in the workplace, the local atomic clock 1 will be used as the time base.

[0027] Step 2: After the atmospheric detection lidar collaborative control device has been powered on and warmed up, the main control module 2 sends a time synchronization start command to each Ethernet control module via Ethernet through the switch 4. After receiving the time synchronization start command, each Ethernet control module sends a time synchronization request to the main control module 2. After receiving the time synchronization request, the main control module 2 records the timestamp t1 of receiving the time synchronization request and includes the timestamp t1 of receiving the time synchronization request in its reply. After receiving the reply, each Ethernet control module records the timestamp t2 of receiving the reply from the main control module 2. Each Ethernet control module calculates the network delay between the corresponding Ethernet control module and the main control module 2 and the current time of the main control module 2 through the corresponding timestamps t1 and t2, and then adjusts the corresponding clock of the Ethernet control module to synchronize with the clock of the main control module 2.

[0028] Step 3: After completing the aforementioned steps, the clocks of each Ethernet control module are synchronized with the clock of the main control module 2, and each Ethernet control module obtains the same reference time T0. The first Ethernet control module 5, the second Ethernet control module 6, the third Ethernet control module 7, and the fourth Ethernet control module 8, based on the reference time T0, drive their respective waveform generators to generate corresponding working module drive control waveforms. Each working module drive control waveform is then sent to its corresponding working module, causing the corresponding working module to begin synchronous operation according to the corresponding working module drive control waveform, thereby achieving precise synchronization of transmission and reception. The specific process is as follows: The first Ethernet control module 5 drives the first waveform generator 11 to generate the corresponding working module drive control waveform of the three-frequency switching device 15 based on the reference time T0, and sends it to the three-frequency switching device 15 so that the three-frequency switching device 15 can start to work synchronously according to the corresponding working module drive control waveform. The second Ethernet control module 6 drives the second waveform generator 12 to generate the corresponding working module drive control waveform of the variable pulse laser 16 based on the reference time T0, and sends it to the variable pulse laser 16, so that the variable pulse laser 16 is triggered to generate pulse laser according to the corresponding working module drive control waveform. The third Ethernet control module 7 drives the third waveform generator 13 to generate the corresponding working module drive control waveform of the programmable chopper 17 based on the reference time T0, and sends it to the programmable chopper 17 so that the programmable chopper 17 starts to work synchronously according to the corresponding working module drive control waveform, that is, it turns on when the laser echo signal arrives. The fourth Ethernet control module 8 drives the fourth waveform generator 14 to generate the corresponding working module drive control waveform of the photon counting acquisition card 18 based on the reference time T0, and sends it to the photon counting acquisition card 18. The photon counting acquisition card 18 starts to work synchronously according to the corresponding working module drive control waveform, that is, it starts acquisition when the echo photon in the echo optical signal arrives. The timing sequence corresponding to the drive control waveforms of each working module is as follows: Figure 2 As shown; Step 4: During the observation process, based on changes in the detection environment and the quality of the echo signal, the master control module 2 sends timing modification commands to the corresponding Ethernet control modules. During observation, if the weather deteriorates and the number of original echo photons in the raw echo data acquired by the photon counting acquisition card 18 decreases, requiring an increase in the number of emitted laser pulses (i.e., increasing the pulse frequency of the laser pulses from 30Hz to 60Hz), the main control module 2 sends a timing modification command to the second Ethernet control module 6, the third Ethernet control module 7, and the fourth Ethernet control module 8, increasing the frequency of the timing of the working module drive control waveform of the variable pulse laser 16 from 30Hz to 60Hz. Simultaneously, the frequencies of the working module drive control waveforms of the programmable chopper 17 and the photon counting acquisition card 18 are also synchronously changed to 60Hz, and the corresponding working module drive control waveforms are regenerated. Figure 3 As shown, the variable pulse laser 16, the programmable chopper 17, and the photon counting and acquisition card 18 start to work synchronously according to the new working module drive control waveform; other frequencies, such as 100Hz, can also be changed in the same way.

[0029] If, during observation, low-altitude signals are found to exceed the dynamic range of the photon counting acquisition card 18, and the low-altitude altitude is less than 30km, it is necessary to remove low-altitude signals at certain altitudes. This requires adjusting the on-time of the programmable chopper 17. The main control module 2 sends a timing modification command to the third Ethernet control module 7, which adjusts the operating module drive control waveform of the programmable chopper 17 to modify its on-time, thereby cutting off the corresponding low-altitude signals. If it is necessary to cut off low-altitude signals at a certain altitude, the change in the on-time of the programmable chopper 17 is calculated according to the following formula. : , in, This refers to the altitude value corresponding to the low-altitude signal that needs to be cut off. It is the speed of light.

[0030] The timing sequence of the working module drive control waveform of the three-frequency switching device 15 includes three-frequency timing sequences F+, F0, and F-. The duration for which the three-frequency timing sequences F+, F0, and F- control the laser pulses to alternate between three frequencies is generally an integer multiple of the number of laser pulses. For example, when the three-frequency timing sequences F+, F0, and F- are at a high level, the corresponding number of laser pulses is 30, indicating that the interval between laser pulse switching frequencies covers 30 laser pulses, meaning that the frequency changes every 30 laser pulses. The corresponding period of the working module drive control waveform of the three-frequency switching device 15 is 3×30, corresponding to a coverage of 90 laser pulses. If it is necessary to adjust the interval between laser pulse switching frequencies, changing it from covering 30 laser pulses to covering 50 laser pulses, then the main control module 2 sends a timing modification command to the first Ethernet control module 5 and the fourth Ethernet control module 8 to regenerate the corresponding working module drive control waveform. The control module 5 sends a timing modification command to modify the period of the timing of the working module drive control waveform (that is, to change the interval of the corresponding laser pulse conversion frequency of the three-frequency timing F+, three-frequency timing F0, and three-frequency timing F- in the timing of the working module drive control waveform of the three-frequency switching device 15 from covering 30 laser pulses to covering 50 laser pulses); at the same time, the main control module 2 sends a timing modification command to the fourth Ethernet control module 8 to synchronize the timing of the Tag signal in the timing of the working module drive control waveform of the photon counting acquisition card 18 with the timing of the working module drive control waveform of the three-frequency switching device 15 (that is, the interval of the timing change of the Tag signal of the photon counting acquisition card 18 is also adjusted to cover 50 laser pulses), thereby completing the timing coordinated adjustment.

[0031] If the local sunrise time changes during the observation period, such as needing to change the day-night switching time from 7:00 AM to 8:00 AM, the main control module 2 will query the current day-night switching time via the Internet or manually input the day-night switching time into the main control module 2. Then, the main control module 2 will send a timing modification command to the fifth Ethernet control module 9 to modify the day-night switching time of the day-night switching device 19.

[0032] If, during the observation period, the data receiver requests a change in the time when the data is transmitted to the data transmission computer 20, the main control module 2 will send a timing modification instruction to the sixth Ethernet control module 10 after receiving the new request, so that the sixth Ethernet control module 10 can start data transmission according to the new time setting. The data transmission computer 20 can also receive remote commands (such as: increasing the frequency of the timing of the driving control waveform of the variable pulse laser 16, the programmable chopper 17, and the photon counting and acquisition card 18 when the original echo photon count decreases; modifying the on-time of the programmable chopper 17 when the low-altitude signal exceeds the dynamic range of the photon counting and acquisition card 18; synchronously modifying the timing of the driving control waveform of the working module of the three-frequency switching device 15 and the timing of the Tag signal of the photon counting and acquisition card 18; modifying the day-night switching time of the day-night switching device 19), and forwarding the remote commands to the main control module 2, which then sends timing modification commands to the corresponding Ethernet control modules to complete the local timing adjustment. The three-frequency switching transceiver coordinated timing adjustment is as follows: Figure 4 As shown.

[0033] Step 5: After the observation is completed, the raw echo data collected by the photon counting acquisition card 18 is uploaded to the data transmission computer 20 for local data inversion, so as to obtain the atmospheric density, wind field and temperature above the observation area; or the raw echo photon count is transmitted to a remote computer via the external network through the data transmission computer 20, and the data inversion is performed on the remote computer to obtain the atmospheric density, wind field and temperature above the observation area.

[0034] This invention enables multi-time-sequence control of atmospheric sounding lidar via Ethernet, and is compatible with automated and intelligent equipment control. It does not rely on traditional analog signal connections, simplifying and integrating the equipment, and facilitating flexible and mobile deployment. Simultaneously, it solves the difficulties of conventional atmospheric sounding lidar control timing, which is not easily adjusted automatically and cannot be read back. This invention uses Ethernet commands to uniformly manage the timing of each component, achieving full digitalization of timing coordination. Because of this digitalization, the timing waveforms during observation can be recorded in real time and used as an important reference for data inversion, effectively improving the quality of atmospheric sounding lidar detection data.

[0035] The specific embodiments described herein are merely illustrative examples of the invention. Those skilled in the art can make various modifications, additions, or substitutions to the described embodiments without departing from the spirit of the invention or exceeding the scope defined outside the appended claims.

Claims

1. A collaborative control device for atmospheric sounding lidar based on Ethernet, characterized in that, The system includes a central control module (2), which is connected to an atomic clock (1), an external network interface module (3), and a switch (4). The switch (4) is connected to each Ethernet control module via Ethernet. The Ethernet control modules include a first Ethernet control module (5), a second Ethernet control module (6), a third Ethernet control module (7), a fourth Ethernet control module (8), a fifth Ethernet control module (9), and a sixth Ethernet control module (10). The first Ethernet control module (5) is connected to a three-frequency switching device (15) via a first waveform generator (11), the second Ethernet control module (6) is connected to a variable pulse laser (16) via a second waveform generator (12), the third Ethernet control module (7) is connected to a programmable chopper (17) via a third waveform generator (13), the fourth Ethernet control module (8) is connected to a photon counting acquisition card (18) via a fourth waveform generator (14), the fifth Ethernet control module (9) is connected to a day / night switching device (19), and the sixth Ethernet control module (10) is connected to a data transmission computer (20).

2. A method for coordinated control of an Ethernet-based atmospheric sounding lidar, utilizing the Ethernet-based atmospheric sounding lidar coordinated control device described in claim 1, characterized in that, Includes the following steps: Step 1: Build an Ethernet-based atmospheric detection lidar collaborative control device. The main control module (2) can be connected to the Internet through the external network interface module (3) or connected to the atomic clock (1). The first Ethernet control module (5), the second Ethernet control module (6), the third Ethernet control module (7), and the fourth Ethernet control module (8) all store the waveforms of the corresponding waveform generator drive signals; Step 2: After the atmospheric detection lidar collaborative control device is powered on and warmed up, the main control module (2) sends a time synchronization start command to each Ethernet control module via Ethernet through the switch (4). After receiving the time synchronization start command, each Ethernet control module sends a time synchronization request to the main control module (2). After receiving the time synchronization request, the main control module (2) records the timestamp t1 of receiving the time synchronization request and includes the timestamp t1 of receiving the time synchronization request in the reply. After receiving the reply, each Ethernet control module records the timestamp t2 of receiving the reply from the main control module (2). Each Ethernet control module calculates the network delay between the corresponding Ethernet control module and the main control module (2) and the current time of the main control module (2) through the corresponding timestamp t1 and timestamp t2, and then adjusts the corresponding clock of the Ethernet control module to synchronize with the clock of the main control module (2). Step 3: After completing the aforementioned steps, each Ethernet control module obtains the same reference time T0; The first Ethernet control module (5), the second Ethernet control module (6), the third Ethernet control module (7) and the fourth Ethernet control module (8) drive their respective waveform generators to generate corresponding working module drive control waveforms based on the reference time T0, and each working module drive control waveform is sent to the corresponding working module so that the corresponding working module starts to work synchronously according to the corresponding working module drive control waveform. Among them, the working module corresponding to the first Ethernet control module (5) is a three-frequency switching device (15), the working module corresponding to the second Ethernet control module (6) is a variable pulse laser (16), the working module corresponding to the third Ethernet control module (7) is a programmable chopper (17), and the working module corresponding to the fourth Ethernet control module (8) is a photon counting acquisition card (18). Step 4: During the observation process, based on changes in the detection environment and the quality of the echo signal, the timing modification command is sent to the corresponding Ethernet control module through the main control module (2); Step 5: After the observation is completed, the original echo data collected by the photon counting acquisition card (18) is uploaded to the data transmission computer (20) for local data inversion, so as to obtain the atmospheric density, wind field and temperature above the observation area; or the original echo photon count is transmitted to the remote computer via the external network through the data transmission computer (20), and the data inversion is performed on the remote computer to obtain the atmospheric density, wind field and temperature above the observation area.

3. The Ethernet-based atmospheric sounding lidar cooperative control method according to claim 2, characterized in that, Step 4 specifically includes the following process: During the observation process, if the number of original echo photons in the original echo count collected by the photon counting acquisition card (18) decreases, the main control module (2) sends a timing modification command to the second Ethernet control module (6), the third Ethernet control module (7) and the fourth Ethernet control module (8) to increase the frequency of the timing of the working module drive control waveform of the variable pulse laser (16). At the same time, the frequency of the timing of the working module drive control waveform of the programmable chopper (17) and the frequency of the timing of the working module drive control waveform of the photon counting acquisition card (18) are also synchronized accordingly.

4. The Ethernet-based atmospheric sounding lidar cooperative control method according to claim 2, characterized in that, Step 4 also includes the following process: If the low-altitude signal is found to exceed the dynamic range of the photon counting acquisition card (18) during the observation process, the main control module (2) sends a timing modification command to the third Ethernet control module (7), and the control waveform is modified by adjusting the working module of the programmable chopper (17) to change the opening duration of the programmable chopper (17); The change in the on-time of the programmable chopper (17) is calculated using the following formula. : ， in, This refers to the altitude value corresponding to the low-altitude signal that needs to be cut off. It is the speed of light.

5. The Ethernet-based atmospheric sounding lidar cooperative control method according to claim 2, characterized in that, Step 4 also includes the following process: If the timing period of the working module drive control waveform of the three-frequency switching device (15) is required, the main control module (2) sends a timing modification command to the first Ethernet control module (5) to modify the timing period of the working module drive control waveform; at the same time, the main control module (2) sends a timing modification command to the fourth Ethernet control module (8) to synchronize the timing of the Tag signal in the timing of the working module drive control waveform of the photon counting acquisition card (18) with the timing of the working module drive control waveform of the three-frequency switching device (15).

6. The Ethernet-based atmospheric sounding lidar cooperative control method according to claim 2, characterized in that, Step 4 also includes the following process: If the local sunrise time changes during the observation period, the main control module (2) first queries the day-night switching time via the Internet or manually inputs the day-night switching time into the main control module (2), and then the main control module (2) sends a timing modification command to the fifth Ethernet control module (9) to modify the day-night switching time of the day-night switching device (19).

7. The Ethernet-based atmospheric sounding lidar cooperative control method according to claim 2, characterized in that, Step 4 also includes the following process: If, during the observation period, the data receiver requests a change in the time when the data is transmitted to the data transmission computer (20), the main control module (2) sends a timing modification instruction to the sixth Ethernet control module (10), causing the sixth Ethernet control module (10) to start data transmission according to the new time setting.

8. The Ethernet-based atmospheric sounding lidar cooperative control method according to claims 3-7, characterized in that, The data transmission computer (20) receives remote instructions and forwards them to the main control module (2), which then sends timing modification instructions to the corresponding Ethernet control module.

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