A method and device for suppressing beat frequency interference in a coherent wind measurement laser radar cooperative observation system, and a medium

Abstract

This invention discloses a method, apparatus, equipment, and medium for suppressing beat frequency interference in a coherent wind-measuring lidar cooperative observation system. The method includes: a signal acquisition and processing module generating a voltage control signal; the voltage control signal being buffered by an operational amplifier and then input to a constant current source module of a continuous laser to adjust the supply current of the laser diode in the continuous laser, thereby adjusting the laser frequency; the i-th coherent wind-measuring lidar performing laser frequency adjustment once after each laser pulse detection via the voltage control signal; and adjusting the frequency every N... i The frequency adjustment is performed cyclically, with the secondary pulse emission constituting a frequency adjustment cycle; where N... i For each positive integer, M ≥ 2. This invention ensures that the power spectrum of the coherent wind lidar is free of interference peaks during continuous long-term observations. By employing a coprime periodic frequency sweep mode, it can achieve continuous observations for several days without beat frequency interference, significantly improving the working stability and data validity of the collaborative observation system.

Description

Technical Field

[0001] This invention relates to a method, device, equipment, and medium for suppressing beat frequency interference in a coherent wind-measuring lidar cooperative observation system, belonging to the field of laser wind measurement technology. Background Technology

[0002] Coherent wind lidar is widely used in meteorological observation, aerospace, wind power operation and maintenance, and other fields. In practical applications, to improve the observation coverage and data density, collaborative observation by multiple coherent wind lidars has become the mainstream configuration. Especially when M lidars (M≥2) share a single telescope system, a three-dimensional, high-precision detection of the target area can be achieved through array-based layout, significantly reducing system deployment costs and space occupation. The working principle of traditional coherent wind lidar is as follows: the pulsed laser output from the laser is expanded by the telescope and emitted into the atmosphere. The echo signal generated by the interaction with atmospheric particles beats with the local oscillator light output from the laser in the coupler. Subsequently, the photoelectric conversion is completed by the balanced detection module. The converted electrical signal is analyzed by the signal acquisition and processing module, and finally, key parameters such as atmospheric wind field and temperature are obtained.

[0003] However, in collaborative observation scenarios, existing technologies suffer from beat frequency interference problems: on the one hand, due to factors such as ambient temperature fluctuations, power supply voltage drift, and laser diode aging, the laser frequency of each coherent wind lidar inevitably experiences a slow drift; on the other hand, when multiple radars share a telescope, the close-range characteristics of optical path coupling significantly increase the difficulty of signal isolation between radars. When the laser frequencies of any two radars (such as radar A and radar B) approach the beat frequency interference threshold due to drift, the echo signal of radar A will unexpectedly beat with the local oscillator light of radar B. After being received by the balanced detector of radar B, this interference signal will be mixed into the power spectrum of the effective detection signal, resulting in a decrease in signal-to-noise ratio and distortion of frequency peaks, which in turn leads to an increase in atmospheric parameter inversion errors, and in severe cases, even causes the detection data to fail.

[0004] Currently, the industry mainly uses hardware isolation (such as adding optical path shielding) and fixed frequency offset (preset initial frequency difference between radars) to suppress interference in coherent wind lidar collaborative observation. However, the former cannot fundamentally solve the dynamic interference caused by frequency drift, and the latter is prone to failure due to long-term drift exceeding the preset frequency difference threshold. Moreover, in the scenario of multiple radars working together, the planning difficulty of fixed frequency offset increases exponentially with the number of radars, making it difficult to adapt to the needs of high-density array-type collaborative observation. Summary of the Invention

[0005] To address the problems existing in the prior art, the present invention provides a method, apparatus, equipment, and medium for suppressing beat frequency interference in a coherent wind lidar cooperative observation system.

[0006] To achieve the above objectives, the present invention employs a beat frequency interference suppression method for a coherent wind lidar cooperative observation system. The coherent wind lidar cooperative observation system includes M coherent wind lidars, each equipped with a continuous laser and a signal acquisition and processing module.

[0007] The beat frequency interference suppression method includes:

[0008] The signal acquisition and processing module generates a voltage control signal, which is buffered by an operational amplifier and then input to the constant current source module of the continuous laser. By controlling the output current of the constant current source module, the power supply current of the laser diode in the continuous laser is adjusted, thereby achieving the adjustment of the laser frequency.

[0009] The i-th coherent wind-measuring lidar performs a laser frequency adjustment once after each laser pulse detection via the voltage control signal; at every N... i The frequency adjustment is performed cyclically as a frequency adjustment cycle, with the next pulse emission constituting a frequency adjustment period; wherein, N i Let i be a positive integer, i = 1, 2, ..., M; M ≥ 2.

[0010] As an improvement, the laser frequency adjustment adopts a coprime periodic frequency sweep mode:

[0011] The adjustment periods N1, N2, ..., N of the coherent wind-measuring lidars described in Unit M are... i They are pairwise coprime.

[0012] As an improvement, M=5, and the adjustment period N of the 5 coherent wind-measuring lidars is... i The numbers are 3, 13, 23, 29, and 31 in sequence.

[0013] As an improvement, the laser frequency adjustment adopts a random periodic frequency sweep mode:

[0014] After each frequency adjustment cycle, the signal acquisition and processing module samples the amplitude of the radar's internal noise signal and randomly generates N for the next frequency adjustment cycle based on the amplitude. i .

[0015] As an improvement, the signal acquisition and processing module generates a voltage control signal through a digital-to-analog converter; the model of the digital-to-analog converter is AD9767ASTZRL; the signal acquisition and processing module adjusts the voltage control signal before each laser pulse is emitted.

[0016] As an improvement, multiple coherent wind lidars share a single telescope to form an array-type collaborative observation system; the wavelength of the continuous laser is 1550nm, and the emission repetition frequency of the laser pulse is 10kHz.

[0017] A second aspect of the present invention also provides a beat frequency interference suppression device for a coherent wind lidar cooperative observation system, for implementing the beat frequency interference suppression method of the coherent wind lidar cooperative observation system; the beat frequency interference suppression device includes:

[0018] The laser frequency adjustment module is used to generate a voltage control signal by the signal acquisition and processing module. The voltage control signal is buffered by an operational amplifier and then input to the constant current source module of the continuous laser. By controlling the output current of the constant current source module, the power supply current of the laser diode in the continuous laser is adjusted, thereby realizing the adjustment of the laser frequency.

[0019] The periodic adjustment module is used by the i-th coherent wind-measuring lidar to perform laser frequency adjustment once after each laser pulse detection via the voltage control signal; at a rate of N... i The frequency adjustment is performed cyclically as a frequency adjustment cycle, with the next pulse emission constituting a frequency adjustment period; wherein, N i Let i be a positive integer, i = 1, 2, ..., M; M ≥ 2.

[0020] A third aspect of the present invention also provides a beat frequency interference suppression device for a coherent wind lidar cooperative observation system, comprising a processor and a memory;

[0021] The memory stores a computer program, which, when executed by a processor, implements the beat frequency interference suppression method of the coherent wind lidar cooperative observation system.

[0022] In a fourth aspect, the present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the beat frequency interference suppression method of the coherent wind lidar cooperative observation system described above.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] 1. This invention achieves laser frequency fine-tuning by controlling the laser diode power supply current, and combined with a periodic frequency sweep strategy, effectively avoids long-term beat frequency interference caused by frequency drift of multiple coherent wind-measuring lidars, and eliminates the situation of second-level interference caused by close frequencies; the coprime periodic frequency sweep mode can achieve long-term observation without beat frequency interference, which greatly shortens the interference duration compared with traditional schemes, ensures the purity of radar detection signals, and ensures accurate and reliable atmospheric parameter inversion results.

[0025] 2. This invention proposes two modes: coprime periodic frequency sweep and random periodic frequency sweep. The coprime periodic frequency sweep mode can maximize the avoidance of frequency overlap and is suitable for high-precision observation scenarios. The random periodic frequency sweep mode does not require pre-setting the coprime period, which greatly reduces the difficulty of building a collaborative observation system, simplifies the debugging process, and balances the suppression effect with the practicality of the system.

[0026] 3. This invention makes targeted improvements to the existing hardware architecture of traditional coherent wind lidar, without requiring significant modifications to the structure or working principle of core functional hardware such as the laser, optical path, and detection module. It only requires two adaptation designs: first, adding an analog voltage output channel to the signal acquisition and processing module; and second, adding a matching analog voltage input channel to the laser. Through these simplified modifications, precise adjustment of the laser frequency can be achieved via voltage control signals. This allows for direct compatibility with mainstream existing coherent wind lidar equipment, ensuring hardware reusability, and minimizing the cost and difficulty of system upgrades.

[0027] 4. This invention is perfectly compatible with array-type observation architectures where multiple radars share a telescope, solving the problems of signal crosstalk and beat frequency interference caused by shared optical paths, improving system integration and space utilization, and meeting the needs of high-density, large-scale collaborative observation. This invention can ensure that the power spectrum of coherent wind lidar has no interference peaks during continuous long-term observations, and the use of coprime periodic frequency sweep mode can achieve continuous observation for several days without beat frequency interference, significantly improving the working stability and data validity of the collaborative observation system. Attached Figure Description

[0028] Figure 1 This is a structural diagram of the coherent wind-measuring lidar used in this invention;

[0029] Figure 2 This is a schematic diagram of the circuit principle for laser frequency adjustment in this invention;

[0030] Figure 3 This is a schematic diagram of the structure of an embodiment of the present invention;

[0031] Figure 4 This is a comparison diagram of the voltage control signal and the laser pulse timing in an embodiment of the present invention. Detailed Implementation

[0032] The following embodiments are further illustrations of the present invention and serve as explanations of the technical content of the present invention. However, the essence of the present invention is not limited to the embodiments described below. Those skilled in the art can and should know that any simple changes or substitutions based on the spirit of the present invention should fall within the protection scope claimed by the present invention.

[0033] Example 1

[0034] likeFigure 1 , Figure 2 and Figure 3 As shown, the coherent wind lidar cooperative observation system in this embodiment is an array-type cooperative observation system, specifically including M coherent wind lidars, 1 shared telescope, and supporting optical path components; M≥2, and the core hardware configuration of each coherent wind lidar is identical, including: a continuous laser, a beam splitter, a chopper frequency shifting amplification module, a circulator, a coupler, a balanced detection module, and a signal acquisition and processing module. The connection relationship of each module is as follows:

[0035] The output of the continuous laser is connected to the input of the beam splitter, which splits the laser into two paths: a probe beam and a local oscillator beam.

[0036] After the probe light is processed by the chopper frequency shifting amplification module, it is transmitted to the common telescope through the circulator. The common telescope expands the beam and emits it into the atmosphere. The atmospheric echo signal is received by the common telescope and transmitted to the coupler through the circulator. It beats with the local oscillator light output from the beam splitter in the coupler.

[0037] The beat frequency signal output by the coupler is input to the balanced detection module, and after being converted into an electrical signal by photoelectric conversion, it is transmitted to the signal acquisition and processing module for further processing.

[0038] The output of the signal acquisition and processing module is connected to the control terminal of the continuous laser, and is used to output a voltage control signal to the continuous laser to achieve fine adjustment of the laser frequency.

[0039] In some embodiments, the hardware used is as follows:

[0040] Continuous laser: wavelength of 1550nm (adapted to atmospheric transmission window, reducing attenuation), laser pulse emission repetition frequency of 10kHz;

[0041] Signal acquisition and processing module: Integrated digital-to-analog converter (DAC), wherein the model of the digital-to-analog converter is AD9767ASTZRL;

[0042] Shared telescope: can provide stable transmission and reception optical paths for M radars simultaneously, reducing optical path crosstalk.

[0043] The beat frequency interference suppression method of the coherent wind lidar cooperative observation system includes the following steps:

[0044] Step 1: System Startup and Initialization

[0045] After the collaborative observation system is started, each coherent wind lidar completes hardware self-test, initializes the signal acquisition and processing module, and clarifies the core operating parameters: the wavelength of the continuous laser is locked at 1550nm, and the emission repetition frequency of the laser pulse is set to 10kHz, ensuring that the basic operating parameters of all radars are consistent, laying the foundation for collaborative observation and interference suppression.

[0046] Step 2: Voltage control signal generation and frequency fine-tuning implementation

[0047] The signal acquisition and processing module generates an analog voltage control signal through a built-in digital-to-analog converter (model AD9767ASTZRL). After the voltage control signal is sent into the continuous laser, it is first buffered by an operational amplifier to reduce signal distortion and improve control stability. The buffered voltage control signal directly acts on the constant current source module of the continuous laser. By changing the output current of the constant current source module, the supply current of the laser diode is adjusted, thereby achieving a slight adjustment of the laser frequency (i.e., frequency fine-tuning).

[0048] It should be noted that the signal acquisition and processing module strictly follows the timing logic of "completing adjustment before pulse emission". Before each laser pulse is emitted, the voltage control signal is adjusted and stabilized to ensure that the frequency of the laser pulse emission has reached the target fine-tuning value, thus avoiding frequency adjustment failure due to timing deviation.

[0049] Step 3: Execution of the periodic frequency sweep strategy

[0050] Each coherent wind-measuring lidar performs frequency adjustment according to a unified timing rhythm: after each laser pulse detection (i.e., after the balanced detection module completes the photoelectric conversion of the pulse echo signal and transmits the electrical signal to the signal acquisition and processing module), the signal acquisition and processing module triggers a voltage control signal adjustment action, causing a slight shift in the laser frequency; at every N... i The secondary pulse emission constitutes a complete frequency adjustment cycle, and the above adjustment action is performed cyclically according to this cycle, where i=1,2,…,M,N i The value is a positive integer. By periodically adjusting the value, the laser frequency of each radar is kept in a dynamic state, avoiding prolonged proximity due to frequency drift.

[0051] This invention provides two periodic frequency sweep modes, and the specific implementation methods are as follows:

[0052] (1) Coprime periodic sweep frequency mode

[0053] This mode is suitable for scenarios requiring high interference suppression and long-term stable observation. The specific implementation method is as follows:

[0054] For each of the M coherent wind-measuring lidars, a frequency adjustment period N1, N2, ..., N is set. i Furthermore, all periods satisfy the condition that they are "pairwise coprime" (i.e., the greatest common divisor of any two periods is 1). By setting coprime periods, the differences in the frequency modulation patterns of each radar are maximized, thereby reducing the probability of multiple radar laser frequencies approaching each other at the same time and thus avoiding beat frequency interference.

[0055] As a preferred implementation case of this model, when M=5, the frequency adjustment periods Nᵢ of the five coherent wind-measuring lidars are set to 3, 13, 23, 29, and 31 respectively. All these periods are prime numbers, naturally satisfying the requirement of pairwise coprime, requiring no additional calculation or verification, and making deployment convenient. Actual observations have verified that the collaborative observation system using this set of periods did not exhibit any characteristic peaks of beat frequency interference in the power spectrum of any of the lidars during a continuous 3-day observation period, demonstrating significant interference suppression.

[0056] (2) Random periodic sweep frequency mode

[0057] This mode is suitable for scenarios with short system setup cycles and flexible adjustments to the number of radars. The specific implementation method is as follows:

[0058] After each coherent wind lidar completes one frequency adjustment cycle, the signal acquisition and processing module actively samples the amplitude of the noise signal. Using this noise signal amplitude as a random seed, N for the next frequency adjustment cycle is generated through preset random logic. i , i=1,2,…,M. In this mode, there is no need to plan each radar N in advance. i The coprime relationship means that even if the number of radars increases or decreases, there is no need to readjust the period parameters, which greatly reduces the difficulty of building and debugging the collaborative observation system. At the same time, the randomness of the period avoids the overlap of frequency patterns, thus effectively suppressing beat frequency interference.

[0059] To clarify the technical effects of this invention, a comparative test was conducted between the traditional non-inhibition method and the method of this invention. The test conditions and results are as follows:

[0060] 1. Test conditions

[0061] System configuration: M=5 coherent wind lidars sharing one telescope, continuous laser wavelength 1550nm, laser pulse repetition frequency 10kHz;

[0062] Observation environment: outdoor conventional meteorological conditions; observation duration is set according to test requirements.

[0063] Interference determination method: The power spectrum of the beat frequency signal is analyzed by the signal acquisition and processing module. If an unexpected clutter peak appears in the power spectrum, it is determined that beat frequency interference exists.

[0064] 2. Test Results

[0065] Traditional unsuppressed method: The system accumulates the power spectrum of 10,000 beat frequency signals every second. Within an hour of observation, all 5 coherent wind lidars have a certain probability of observing clutter peaks of beat frequency interference. The duration of interference can reach the order of seconds, affecting the accuracy of the detection data.

[0066] The coprime periodic sweep frequency mode of this invention (N i =3, 13, 23, 29, 31; that is, the adjustment period of the first coherent wind lidar is 3, the adjustment period of the second coherent wind lidar is 13, the adjustment period of the third coherent wind lidar is 23, the adjustment period of the fourth coherent wind lidar is 29, and the adjustment period of the fifth coherent wind lidar is 31): After three consecutive days (72 hours) of observation, no beat frequency interference clutter peaks appeared in the power spectrum of all coherent wind lidars, and the detection data was stable and reliable, verifying the effectiveness of interference suppression of this mode. Figure 4 This is a time-series comparison diagram of the voltage control signal and laser pulses of the first coherent wind-measuring lidar.

[0067] Example 2

[0068] This embodiment discloses a beat frequency interference suppression device for a coherent wind lidar cooperative observation system. The device corresponds to the beat frequency interference suppression method described in Embodiment 1 and is used to implement the technical process of the method. It is suitable for an array-type cooperative observation system composed of M coherent wind lidars (M≥2).

[0069] The beat frequency interference suppression device specifically includes the following modules:

[0070] (1) Laser frequency adjustment module

[0071] This module is the core execution unit for frequency fine-tuning. Its core function is to achieve precise adjustment of the laser frequency through voltage control. The specific implementation logic is as follows:

[0072] The system receives control commands from the signal acquisition and processing module, drives the digital-to-analog converter to generate a target voltage control signal, transmits the voltage control signal to the operational amplifier for buffering, eliminates signal distortion and improves control stability, and inputs the buffered voltage control signal to the constant current source module of the continuous laser. By adjusting the output current of the constant current source module, the power supply current of the laser diode is indirectly adjusted, ultimately achieving a slight shift in the laser frequency (i.e., frequency fine-tuning), providing a basis for subsequent periodic frequency sweeps.

[0073] (2) Periodic adjustment module

[0074] This module is the timing control unit for the frequency sweeping strategy, used to coordinate the frequency adjustment rhythm of each radar. The specific implementation logic is as follows:

[0075] Based on the preset timing triggering rules, after each coherent wind-measuring lidar completes the detection of a single laser pulse (i.e., after the balanced detection module outputs the detection electrical signal of the pulse), the laser frequency adjustment module is triggered to perform a voltage control signal adjustment, thereby completing a laser frequency fine-tuning.

[0076] Preset frequency adjustment period parameter N i (N) i (where N is a positive integer) i The secondary pulse emission constitutes a complete adjustment cycle, controlling the laser frequency adjustment module to repeatedly perform adjustment actions according to this cycle; it also supports switching between coprime periodic frequency sweep mode and random periodic frequency sweep mode. When using the coprime periodic frequency sweep mode, it coordinates the N1, N2, ..., N of the M radars. i The parameters must be pairwise coprime; when using a random periodic frequency sweep mode, the noise signal sampling data is received and the next period's N is generated. i This ensures flexible adaptation of the frequency scanning strategy.

[0077] Example 3

[0078] This embodiment discloses a beat frequency interference suppression device for a coherent wind lidar cooperative observation system. This device serves as the hardware carrier for the aforementioned beat frequency interference suppression method and apparatus, specifically including a processor and a memory, wherein:

[0079] Memory: Utilizes non-volatile storage media (such as solid-state drives and flash memory) to store computer programs and system configuration parameters required for operation (including continuous laser wavelength, laser pulse repetition frequency, N...). i (Initial value, frequency sweep mode selection, etc.), the computer program is a set of codes for implementing the beat frequency interference suppression method described in Embodiment 1, including functional logic such as voltage control signal generation, period scheduling, frequency adjustment, noise sampling, and random period generation;

[0080] Processor: A high-performance microprocessor (such as ARM Cortex-A series or FPGA chip) is used to call and execute the computer program stored in the memory. Through hardware drive and signal control, it links the signal acquisition and processing module of the coherent wind lidar, the continuous laser and other hardware to complete the entire process of beat frequency interference suppression, ensuring the accuracy of the adjustment timing and the stability of the system operation.

[0081] This embodiment also discloses a computer-readable storage medium, which is a non-temporary storage medium capable of storing computer program instructions (including USB flash drive, mobile hard drive, read-only memory ROM, random access memory RAM, magnetic disk, optical disk, etc.). The computer program is stored on it. When the computer program is executed by a processor (such as the processor of the device described in Embodiment 3), it can fully implement the beat frequency interference suppression method of the coherent wind lidar cooperative observation system described in Embodiment 1, including all technical features such as laser frequency fine-tuning, periodic frequency sweep strategy execution, and switching between two frequency sweep modes. It can be directly applied to the upgrade and transformation of existing coherent wind lidar cooperative observation systems without significant changes to the hardware structure, and has strong adaptability.

[0082] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions or improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for suppressing beat frequency interference in a coherent wind-measuring lidar cooperative observation system, characterized in that, The coherent wind lidar collaborative observation system includes M coherent wind lidars, each equipped with a continuous laser and a signal acquisition and processing module. The beat frequency interference suppression method includes: The signal acquisition and processing module generates a voltage control signal, which is buffered by an operational amplifier and then input to the constant current source module of the continuous laser. By controlling the output current of the constant current source module, the power supply current of the laser diode in the continuous laser is adjusted, thereby achieving the adjustment of the laser frequency. The i-th coherent wind-measuring lidar performs a laser frequency adjustment once after each laser pulse detection via the voltage control signal; at every N... i The frequency adjustment is performed cyclically as a frequency adjustment cycle, with the next pulse emission constituting a frequency adjustment period; wherein, N i Let i be a positive integer, i = 1, 2, ..., M; M ≥ 2.

2. The method for suppressing beat frequency interference in a coherent wind lidar cooperative observation system according to claim 1, characterized in that, The laser frequency is adjusted using a coprime periodic frequency sweep mode: The adjustment periods N1, N2, ..., N of the coherent wind-measuring lidars described in Unit M are... i They are pairwise coprime.

3. The method for suppressing beat frequency interference in a coherent wind lidar cooperative observation system according to claim 2, characterized in that, The M=5, and the adjustment period N of the 5 coherent wind-measuring lidars. i The numbers are 3, 13, 23, 29, and 31 in sequence.

4. The method for suppressing beat frequency interference in a coherent wind lidar cooperative observation system according to claim 1, characterized in that, The laser frequency is adjusted using a random periodic frequency sweep mode: After each frequency adjustment cycle, the signal acquisition and processing module samples the amplitude of the radar's internal noise signal and randomly generates N for the next frequency adjustment cycle based on the amplitude. i .

5. The method for suppressing beat frequency interference in a coherent wind lidar cooperative observation system according to claim 1, characterized in that, The signal acquisition and processing module generates a voltage control signal through a digital-to-analog converter; the model of the digital-to-analog converter is AD9767ASTZRL; the signal acquisition and processing module adjusts the voltage control signal before each laser pulse is emitted.

6. The method for suppressing beat frequency interference in a coherent wind lidar cooperative observation system according to claim 1, characterized in that, Multiple coherent wind lidars share a single telescope, forming an array-type collaborative observation system; the wavelength of the continuous laser is 1550nm, and the emission repetition frequency of the laser pulse is 10kHz.

7. A beat frequency interference suppression device for a coherent wind-measuring lidar cooperative observation system, characterized in that, A method for suppressing beat frequency interference in the coherent wind lidar cooperative observation system as described in any one of claims 1-6; The beat frequency interference suppression device includes: The laser frequency adjustment module is used to generate a voltage control signal by the signal acquisition and processing module. The voltage control signal is buffered by an operational amplifier and then input to the constant current source module of the continuous laser. By controlling the output current of the constant current source module, the power supply current of the laser diode in the continuous laser is adjusted, thereby realizing the adjustment of the laser frequency. The periodic adjustment module is used by the i-th coherent wind-measuring lidar to perform laser frequency adjustment once after each laser pulse detection via the voltage control signal; at a rate of N... i The frequency adjustment is performed cyclically as a frequency adjustment cycle, with the next pulse emission constituting a frequency adjustment period; wherein, N i Let i be a positive integer, i = 1, 2, ..., M; M ≥ 2.

8. A beat frequency interference suppression device for a coherent wind-measuring lidar cooperative observation system, characterized in that, Including processor and memory; The memory stores a computer program, which, when executed by a processor, implements the beat frequency interference suppression method of the coherent wind lidar cooperative observation system according to any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, It stores a computer program that, when executed by a processor, implements the beat frequency interference suppression method of the coherent wind lidar cooperative observation system according to any one of claims 1-6.

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