Wind measurement laser radar system and method based on quantum interference

Abstract

This invention provides a wind-measuring lidar system and method based on quantum interference. The laser provides pulsed laser and continuous laser. The pulsed laser is emitted into the target airspace and backscattered signals are received. The continuous laser is divided into a first interferometric local oscillator and a second interferometric local oscillator. The second interferometric local oscillator is adjusted to obtain a quantum interferometric local oscillator whose intensity is proportional to the intensity of the backscattered signal. The backscattered signal is switched to a classical or quantum interferometric detection channel. Classical interferometric detection data is obtained in the classical interferometric detection channel, and a first wind speed information is calculated accordingly. A first single-photon detection data and a second single-photon detection data are obtained in the quantum interferometric detection channel, and a second wind speed information is calculated accordingly. The first and second wind speed information data are spliced ​​and interpolated to supplement the missing wind speed information data caused by the response time of the optical switch, thereby obtaining the wind speed information of the target airspace.

Description

Technical Field

[0001] This invention relates to the fields of lidar and lidar speed measurement technology, and in particular to a wind-measuring lidar system and method based on quantum interference. Background Technology

[0002] Accurate atmospheric wind field measurement is of great significance in many fields, such as numerical weather prediction, wind resource assessment, airport wind shear warning, and atmospheric physics research. Common instruments for measuring atmospheric wind fields include ultrasonic anemometers, weather balloons, wind-measuring microwave radar, and wind-measuring lidar. Among these, wind-measuring lidar has the advantages of high spatiotemporal resolution, good stability, and high measurement accuracy, and has been widely used. The world's first coherent wind-measuring lidar used continuous light as the detection source and achieved distance resolution by changing the focusing position. Later, coherent wind-measuring lidar using pulsed light sources gradually emerged, which can detect atmospheric wind speed profiles without adjusting the optical structure. In recent years, more and more research institutions have invested in the development of coherent wind lidar. The principle of existing coherent wind lidar is as follows: a laser generates continuous light, which is split into two parts by an optical fiber beam splitter. One part is used as the local oscillator light, and the other part is modulated by an acousto-optic modulator and then amplified by an optical fiber amplifier. After passing through a circulator, the light is emitted from the telescope into the atmosphere. After acting on the atmosphere, the backscattered signal of atmospheric aerosol particles is received by the telescope again. After passing through the circulator, it is mixed with the local oscillator light in an optical fiber coupler and then enters the photodetector for detection. Since the bandwidth of the photodetector is limited, only the beat frequency can be retrieved. The beat frequency is the superposition of the frequency shift of the acousto-optic modulator and the Doppler frequency shift generated by the wind speed. From this, the atmospheric wind field information can be calculated.

[0003] The main limitation of coherent wind lidar lies in its detection of backscattered signals from atmospheric aerosol particles (the signals from molecular scattering exhibit strong Doppler broadening, making their first-order interference signals undetectable by the detector). Since the concentration of aerosol particles decreases rapidly with increasing altitude, the maximum detection altitude of most existing coherent lidars is only a few kilometers. To detect wind fields at higher altitudes, high-precision frequency discriminators are typically used to directly analyze the frequency shift of the molecular scattering echo signals, thereby calculating atmospheric wind speed—a method known as direct detection. This approach can usually extend the detection altitude of atmospheric wind fields to 60 km; however, direct detection is very expensive and suffers from poor stability and accuracy.

[0004] In summary, coherent wind-measuring lidar cannot detect high altitudes, while direct wind-measuring lidar is too expensive and suffers from poor stability and accuracy. Therefore, there is an urgent need for a low-cost, more stable, and accurate wind-measuring lidar and method. Summary of the Invention

[0005] In view of the above, in order to at least partially solve at least one of the aforementioned technical problems, the present invention provides a wind measurement lidar system and method based on quantum interference, the technical solution of which is as follows:

[0006] According to one embodiment of the present invention, a wind lidar system based on quantum interference is provided, comprising: a laser, a transmitting and receiving assembly, a beam splitter, an optical switch, an intensity modulator, a classical interferometric detection channel, a quantum interferometric detection channel, and a data processing unit, wherein: the laser is configured to provide pulsed laser and continuous laser; the transmitting and receiving assembly is configured to emit the pulsed laser into a target airspace and receive backscattered signals generated by the atmosphere in the target airspace; the beam splitter is configured to split the continuous laser into a first interferometric local oscillator beam and a second interferometric local oscillator beam; the intensity modulator is configured to adjust the power intensity of the second interferometric local oscillator beam to obtain a quantum interferometric local oscillator beam whose intensity is proportional to the intensity of the backscattered signal; the optical switch is configured to switch the backscattered signal to the classical interferometric detection channel or the quantum interferometric detection channel; in the classical interferometric detection channel, the backscattered signal... The backscattered signal is coupled with the first interferometric local oscillator to obtain a classical interference signal, and the classical interference signal is detected to obtain classical interference detection data. In the quantum interference detection channel, the backscattered signal is quantum interfered with the quantum interference local oscillator to obtain a first single-photon signal and a second single-photon signal, and the first single-photon signal and the second single-photon signal are detected to obtain first single-photon detection data and second single-photon detection data, respectively. The data processing unit is configured to collect the classical interference detection data and calculate the first wind speed information data, collect the first single-photon detection data and the second single-photon detection data and calculate the second wind speed information data, and perform data splicing and spline interpolation on the first wind speed information data and the second wind speed information data to supplement the partially missing wind speed information data caused by the inherent response time of the optical switch when switching the backscattered signal, so as to obtain the wind speed information of the target airspace.

[0007] According to an embodiment of the present invention, the quantum interference detection channel includes a second fiber coupler and a second single-photon detector. The second fiber coupler is configured to perform quantum interference between the backscattered signal entering the quantum interference detection channel and the quantum interference local oscillator light, generating a first single-photon signal and a second single-photon signal; the first single-photon detector is configured to detect the first single-photon signal to obtain first single-photon detection data; the second single-photon detector is configured to detect the second single-photon signal to obtain second single-photon detection data.

[0008] According to an embodiment of the present invention, the intensity modulator is configured to turn off the transmission of the second interfering local oscillator light for 1 second every set time interval, so that the first single-photon detector and the second single-photon detector detect only the backscattered signal to obtain the backscattered signal intensity, and then the intensity of the second interfering local oscillator light is adjusted by the intensity modulator to 1.7 times the backscattered signal intensity.

[0009] According to an embodiment of the present invention, the transmitting and receiving assembly includes a telescope and a circulator. The telescope is configured to emit a pulsed laser into a target airspace and to receive backscattered signals generated by the atmosphere in the target airspace under the action of the pulsed laser; the circulator is configured to emit the pulsed laser incident by the laser into the telescope and is adapted to emit the backscattered signals received by the telescope into an optical switch.

[0010] According to an embodiment of the present invention, the data processing unit includes a first high-speed acquisition card, a second high-speed acquisition card, and a computer. The first high-speed acquisition card is configured to acquire classical interferometric detection data; the second high-speed acquisition card is configured to acquire first single-photon detection data and second single-photon detection data to obtain quantum interferometric detection data; the computer is configured to calculate wind speed based on the classical interferometric detection data and the quantum interferometric detection data using Doppler frequency shift.

[0011] According to an embodiment of the present invention, when the detection altitude is less than 15 km, the optical switch switches the backscattered signal to the classical interferometric detection channel. When the detection altitude is greater than 15 km, the optical switch switches the backscattered signal to the quantum interferometric detection channel.

[0012] According to an embodiment of the present invention, the classical interferometric detection channel includes a first fiber coupler and a balanced photodetector. The first fiber coupler is configured to couple the backscattered signal entering the classical interferometric detection channel with the first interferometric local oscillator light to generate a classical interferometric signal; the balanced photodetector is configured to detect the classical interferometric signal and convert it into an electrical signal to obtain classical interferometric detection data.

[0013] According to another embodiment of the present invention, a wind measurement method based on quantum interferometry is also provided, comprising: emitting a pulsed laser into a target airspace and receiving backscattered signals generated by the atmosphere in the target airspace under the action of the pulsed laser; dividing the continuous laser into a first interferometric local oscillator beam and a second interferometric local oscillator beam; when the detection height is less than a switching threshold, switching the backscattered signal to a classical interferometric detection channel and coupling it with the first interferometric local oscillator beam to obtain a classical interferometric signal, and detecting the classical interferometric signal to obtain classical interferometric detection data; and calculating a first wind speed information number in the target airspace below the switching threshold based on the classical interferometric detection data. According to the method, the power intensity of the second interferometric local oscillator light is adjusted to obtain a quantum interference local oscillator light with an intensity proportional to the backscattered signal intensity. When the detection height is greater than the switching threshold, the backscattered signal is switched to the quantum interference detection channel to perform quantum interference with the quantum interference local oscillator light to obtain a first single-photon signal and a second single-photon signal. The first single-photon signal and the second single-photon signal are then detected to obtain first single-photon detection data and second single-photon detection data, respectively. Based on the first single-photon detection data and the second single-photon detection data, the second wind speed information data in the target airspace above the switching threshold is calculated.

[0014] According to an embodiment of the present invention, the switching threshold is 15km. When the detection altitude is higher than 15km, the backscattered signal is switched to the quantum interference detection channel through an optical switch. When the detection altitude is lower than 15km, the backscattered signal is switched to the classical interference detection channel through an optical switch.

[0015] According to an embodiment of the present invention, a first wind speed information data is obtained based on classical interferometric detection data, and a second wind speed information data is obtained based on a first single-photon detection data and a second single-photon detection data. The first wind speed information data and the second wind speed information data are spliced ​​together and cubic spline interpolation is performed to supplement the partially missing wind speed information data caused by the inherent response time of the optical switch when switching the backscattered signal, so as to finally obtain the wind speed information of the target airspace. Attached Figure Description

[0016] The objects, features, and advantages of the present invention will become clearer from the following description of embodiments of the invention with reference to the accompanying drawings, in which:

[0017] Figure 1 This is a schematic diagram of a wind-measuring lidar system based on quantum interference, according to an embodiment of the present invention.

[0018] Figure 2 This is a schematic flowchart of the wind measurement method based on quantum interference according to an embodiment of the present invention. Detailed Implementation

[0019] This invention provides a wind-measuring lidar system and method based on quantum interference, which can be used for atmospheric wind field detection. It has the advantages of low cost, stability and accuracy. The detection method combines classical interference and quantum interference, which can extend the wind speed detection altitude to tens of kilometers.

[0020] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0021] In this embodiment of the invention, a wind-measuring lidar system based on quantum interference is provided, such as... Figure 1 As shown, the wind-measuring lidar system includes a laser 1, a transmitting and receiving assembly 2, a beam splitter 3, an optical switch 4, an intensity modulator 7, a classical interferometric detection channel, a quantum interferometric detection channel, and a data processing unit 11.

[0022] Laser 1 is configured to provide both pulsed and continuous laser light. The pulsed laser is used as a signal beam emitted into the target airspace, while the continuous laser is used as a reference beam. There is a 100 MHz frequency difference between the continuous and pulsed lasers.

[0023] The transmitting and receiving component 2 is configured to emit a pulsed laser into a target airspace and receive backscattered signals generated by the atmosphere in the target airspace. Specifically, the transmitting and receiving component 2 includes a telescope and a circulator: the telescope is configured to emit a pulsed laser into the target airspace, and after the pulsed laser is emitted into the target airspace, it interacts with aerosol particles and molecules in the atmosphere of the target airspace to generate backscattered signals, and the telescope receives the backscattered signals generated by the atmosphere in the target airspace under the action of the pulsed laser; the circulator is configured to emit the pulsed laser incident by the laser into the telescope, and is adapted to emit the backscattered signals received by the telescope into the optical switch 4.

[0024] Beam splitter 3 is configured to split the continuous laser beam into a first interferometric local oscillator beam and a second interferometric local oscillator beam. The splitting ratio of beam splitter 3 is 99:1, with the first interferometric local oscillator beam accounting for 99% and the second interferometric local oscillator beam accounting for 1%.

[0025] Optical switch 4 is configured to switch the backscattered signal to either a classical interferometric detection channel or a quantum interferometric detection channel. Optical switch 4 is an electro-optical switch with a switching time of less than 200 ns.

[0026] In the classical interferometric detection channel, the backscattered signal is coupled with the first interferometric local oscillator light to obtain the classical interferometric signal, and the classical interferometric signal is detected to obtain classical interferometric detection data. Specifically, the classical interferometric detection channel includes a first fiber coupler 5 and a balanced photodetector 6. The first fiber coupler 5 is used to couple the backscattered signal entering the classical interferometric detection channel with the first interferometric local oscillator light to generate the classical interferometric signal. The balanced photodetector 6 is used to detect the classical interferometric signal and convert it into an electrical signal to obtain the classical interferometric detection data.

[0027] An intensity modulator is configured to adjust the power intensity of the second interferometric local oscillator light to obtain quantum interference local oscillator light with an intensity proportional to the backscattered signal intensity. After multiple experimental verifications and effect comparisons, it is preferred to adjust the intensity of the second interferometric local oscillator light to 1.7 times the backscattered signal intensity using the intensity modulator. Specifically, every set time interval (e.g., every hour), the transmission of the second interferometric local oscillator light is turned off for 1 second, allowing the first and second single-photon detectors to detect only the backscattered signal to obtain the backscattered signal intensity. Then, the intensity of the second interferometric local oscillator light is adjusted by the intensity modulator to 1.7 times the backscattered signal intensity, thus obtaining the quantum interference local oscillator light. The intensity modulator can be, for example, an electro-optic intensity modulator.

[0028] In the quantum interference detection channel, the backscattered signal undergoes quantum interference with the power-intensity-adjusted quantum interference local oscillator light to obtain a first single-photon signal and a second single-photon signal. These signals are then detected by two single-photon detectors to obtain first and second single-photon detection data. The quantum interference detection channel includes a second fiber coupler 8, a first single-photon detector 9, and a second single-photon detector 10. The second fiber coupler 8 is configured to cause quantum interference between the backscattered signal entering the quantum interference detection channel and the power-intensity-adjusted quantum interference local oscillator light, generating the first and second single-photon signals. The first single-photon detector 9 is configured to detect the first single-photon signal to obtain the first single-photon detection data; the second single-photon detector 10 is configured to detect the second single-photon signal to obtain the second single-photon detection data.

[0029] The data processing unit is configured to acquire classical interferometric detection data and calculate the first wind speed information data, acquire the first single-photon detection data and the second single-photon detection data and calculate the second wind speed information data, and perform data stitching and spline interpolation on the first and second wind speed information data to supplement the partially missing wind speed information data caused by the inherent response time of the optical switch when switching backscattered signals, thus obtaining the wind speed information in the target airspace. The data processing unit includes: a first high-speed acquisition card, a second high-speed acquisition card, and a computer. The sampling frequency of the first and second high-speed acquisition cards is 500MHz. The first high-speed acquisition card is configured to acquire classical interferometric detection data. The second high-speed acquisition card is configured to acquire first and second single-photon detection data to obtain quantum interferometric detection data. For example, after the first single-photon detector 9 and the second single-photon detector 10 detect photon signals, their arrival times are recorded by the second high-speed acquisition card. The computer is configured to calculate wind speed based on the classical and quantum interferometric detection data using Doppler frequency shift. For example, based on the classical interferometric detection data, a wind speed can be calculated within each segment, thus obtaining a classical interferometric wind speed profile. An interference spectrum is calculated based on the quantum interferometric detection data, and the Doppler frequency shift is extracted from it for wind speed calculation. A wind speed can be calculated within each segment, thus obtaining a quantum interferometric wind speed profile. The classical and quantum interferometric wind speed profiles are integrated to obtain a complete wind speed profile for the target airspace. This wind speed profile can be displayed and stored.

[0030] According to an embodiment of the present invention, a classical interferometric detection channel is configured to detect wind speed in the airspace below 15 km altitude, and a quantum interferometric detection channel is configured to detect wind speed in the airspace above 15 km altitude. Therefore, when the detection altitude is greater than 15 km, the backscattered signal is switched to the quantum interferometric detection channel via an optical switch. When the detection altitude is less than 15 km, the backscattered signal is switched to the classical interferometric detection channel via an optical switch.

[0031] Another aspect of the present invention provides a wind measurement method based on quantum interference, such as... Figure 2 As shown, the wind measurement method based on quantum interference includes the following operations:

[0032] S1: The pulsed laser is emitted into the target airspace and the backscattered signal generated by the atmosphere in the target airspace under the action of the pulsed laser is received;

[0033] S2: The continuous laser beam is divided into the first interference local oscillator beam and the second interference local oscillator beam;

[0034] S3: When the detection height is less than the switching threshold, the backscattered signal is switched to the classical interferometric detection channel and coupled with the first interferometric local oscillator to obtain the classical interferometric signal, and the classical interferometric signal is detected to obtain classical interferometric detection data;

[0035] S4: Calculate the first wind speed information data in the target airspace below the switching threshold based on classical interferometric detection data;

[0036] S5: Adjust the power intensity of the second interference local oscillator light to obtain a quantum interference local oscillator light whose intensity is in a set ratio to the intensity of the backscattered signal;

[0037] S6: When the detection height is greater than the switching threshold, the backscattering signal is switched to the quantum interference detection channel and quantum interference with the local oscillator light after the power intensity is adjusted to obtain the first single-photon signal and the second single-photon signal. The first single-photon signal and the second single-photon signal are then detected to obtain the first single-photon detection data and the second single-photon detection data.

[0038] S7: Calculate the second wind speed information data in the target airspace that is higher than the switching threshold based on the first single-photon detection data and the second single-photon detection data.

[0039] According to an embodiment of the present invention, the altitude switching threshold is set to 15km. When the detection altitude is higher than 15km, for example, 30km, 40km, 50km, 60km, 70km, or 80km, the backscattered signal is switched to the quantum interference detection channel via optical switch 4. When the detection altitude is lower than 15km, for example, 5km, 10km, or 15km, the backscattered signal is switched to the classical interference detection channel via optical switch 4. By applying and maintaining different control voltages to optical switch 4, the switching between the classical interference detection channel and the quantum interference detection channel is achieved. The first wind speed information data and the second wind speed information data are stitched together and subjected to cubic spline interpolation to supplement the missing wind speed information data caused by the inherent response time of the optical switch when switching the backscattered signal. Finally, the wind speed information obtained from different altitudes is integrated to obtain atmospheric wind field data in the airspace from near the ground to tens of kilometers in altitude.

[0040] According to an embodiment of the present invention, laser 1 is a seed-injected diode-pumped Nd:YAG laser. The pulsed laser output from laser 1 is emitted into the target space after passing through the circulator and telescope in the transmitting and receiving assembly 2. The linewidth of the pulsed laser is less than 5 MHz, the single pulse energy of the output 1064 nm pulsed laser is 300 mJ, the repetition frequency is 100 Hz, and the divergence angle is less than 150°. The telescope is a 250mm diameter off-axis dual-reflection telescope with a beam magnification of 40x. The telescope mirror is coated with a 1064nm wavelength high-reflectivity film. The circulator is a three-port circulator suitable for 1064nm wavelength. Simultaneously, laser 1 outputs a continuous laser beam with a frequency difference of 100MHz from the pulsed laser to beam splitter 3. Beam splitter 3 splits the continuous laser beam at a ratio of 99:1. The resulting first interference local oscillator beam accounts for 99% of the total beam, and the second interference local oscillator beam accounts for 1%. The second interference local oscillator beam is input to intensity modulator 7, where its power intensity is adjusted to a set ratio with the backscattered signal intensity, resulting in a power intensity-adjusted quantum interference local oscillator beam. The pulsed laser emitted into the target airspace interacts with the atmosphere to generate a backscattered signal. This backscattered signal is then transmitted via a telescope and circulator to optical switch 4. The real-time detection altitude is determined based on the time-of-flight of the laser radar system's detection light signal. When the detection altitude is less than 15 km, optical switch 4 switches the backscattered signal to a classical interferometric detection channel, which enters the first fiber coupler 5. This couples the backscattered signal with the first interferometric local oscillator light, generating a classical interferometric signal, which is then transmitted to a balanced photodetector 6 for photoelectric conversion, yielding classical interferometric detection data. The balanced photodetector 6 has a bandwidth of 200 MHz and a gain of 20 kV / W@50Ω. When the detection altitude is greater than 15 km, optical switch 4 switches the backscattered signal to a quantum interferometric detection channel, which enters the second fiber coupler 8. This couples the backscattered signal with the quantum interferometric local oscillator light, resulting in a first single-photon signal and a second single-photon signal. The first single-photon detector 9 detects the photons in the first single-photon signal, obtaining the first single-photon detection data. The second single-photon detector 10 detects photons in the second single-photon signal to obtain second single-photon detection data. Finally, the data processing unit collects classical interferometric detection data, first single-photon detection data, and second single-photon detection data, and calculates the wind speed information at different altitudes in the target airspace.

[0041] It should be noted that the types and parameter settings of components such as lasers, transmitting and receiving components, optical switches, beam splitters, fiber optic couplers, and detectors in the wind measurement lidar system can be adjusted and replaced according to the actual application.

[0042] The wind-measuring lidar system and method based on quantum interference of the present invention combine classical interferometry and quantum interferometry. At altitudes with strong backscattering signals, classical interferometry is used to obtain wind speed information in the low-altitude airspace, while at altitudes with weak backscattering signals, quantum interferometry is used to obtain wind speed information in the high-altitude airspace. This can greatly improve the carrier-to-noise ratio of the detection, thereby achieving atmospheric wind speed detection in higher airspaces.

[0043] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. It should be noted that implementations not illustrated or described in the drawings or the main text of the specification are forms known to those skilled in the art and have not been described in detail. The specific embodiments described above further illustrate the purpose, technical solutions, and beneficial effects of the present invention. It should be understood that the above are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A wind-measuring lidar system based on quantum interference, characterized in that, include: The system includes a laser, transmitting and receiving components, a beam splitter, an optical switch, an intensity modulator, a classical interferometric detection channel, a quantum interferometric detection channel, and a data processing unit, among which: The laser is configured to provide both pulsed and continuous laser light. The transmitting and receiving components are configured to emit the pulsed laser into the target airspace and receive backscattered signals generated by the atmosphere in the target airspace; The beam splitter is configured to split the continuous laser beam into a first interferometric local oscillator beam and a second interferometric local oscillator beam; An intensity modulator is configured to adjust the power intensity of the second interferometric local oscillator light to obtain a quantum interference local oscillator light with an intensity proportional to the intensity of the backscattered signal. The optical switch is configured to switch the backscattered signal to either a classical interferometric detection channel or a quantum interferometric detection channel; In the classical interferometric detection channel, the backscattered signal is coupled with the first interferometric local oscillator to obtain a classical interferometric signal, and the classical interferometric signal is detected to obtain classical interferometric detection data; in the quantum interferometric detection channel, the backscattered signal is quantumly interfered with the quantum interferometric local oscillator to obtain a first single-photon signal and a second single-photon signal, and the first single-photon signal and the second single-photon signal are detected respectively to obtain first single-photon detection data and second single-photon detection data; The data processing unit is configured to collect the classical interferometric detection data and calculate the first wind speed information data, collect the first single-photon detection data and the second single-photon detection data and calculate the second wind speed information data, and perform data splicing and spline interpolation on the first wind speed information data and the second wind speed information data to supplement the partially missing wind speed information data caused by the inherent response time of the optical switch when the optical switch switches the backscattered signal, so as to obtain the wind speed information of the target airspace.

2. The wind-measuring lidar system based on quantum interference according to claim 1, characterized in that, The quantum interference detection channel includes: The second fiber coupler is configured to perform quantum interference between the backscattered signal entering the quantum interference detection channel and the quantum interference local oscillator light, generating a first single-photon signal and a second single-photon signal; The first single-photon detector is configured to detect the first single-photon signal to obtain first single-photon detection data; The second single-photon detector is configured to detect the second single-photon signal to obtain second single-photon detection data.

3. The wind-measuring lidar system based on quantum interference according to claim 2, characterized in that, The intensity modulator is configured to shut off the transmission of the second interfering local oscillator light for 1 second every set time interval, so that the first single-photon detector and the second single-photon detector detect only the backscattered signal to obtain the intensity of the backscattered signal, and then adjust the intensity of the second interfering local oscillator light to 1.7 times the intensity of the backscattered signal by the intensity modulator.

4. The wind-measuring lidar system based on quantum interference according to claim 1, characterized in that, The transmitting and receiving components include: The telescope is configured to emit the pulsed laser into the target airspace and to receive the backscattered signal generated by the atmosphere in the target airspace under the action of the pulsed laser. A circulator is configured to output a pulsed laser beam incident from a laser to a telescope, and is adapted to output the backscattered signal received by the telescope to the optical switch; The data processing unit includes: The first high-speed acquisition card was configured to acquire classical interferometric detection data; The second high-speed acquisition card is configured to acquire the first single-photon detection data and the second single-photon detection data to obtain quantum interference detection data; A computer is configured to calculate wind speed based on the classical interferometric detection data and the quantum interferometric detection data via Doppler frequency shift.

5. The wind-measuring lidar system based on quantum interference according to claim 1, characterized in that, When the detection altitude is less than 15km, the optical switch will switch the backscattered signal to the classical interferometric detection channel.

6. The wind lidar system based on quantum interference according to claim 1, characterized in that, When the detection altitude is greater than 15km, the optical switch will switch the backscattered signal to the quantum interference detection channel.

7. The wind-measuring lidar system based on quantum interference according to claim 1, characterized in that, The classic interferometric detection channel includes: A first fiber coupler is configured to couple the backscattered signal entering the classical interferometric detection channel with the first interferometric local oscillator light to generate a classical interferometric signal; A balanced photodetector is configured to detect the classical interferometric signal and convert it into an electrical signal to obtain classical interferometric detection data.

8. A wind measurement method based on quantum interference, characterized in that, include: The pulsed laser is emitted into the target airspace, and the backscattered signal generated by the atmosphere in the target airspace under the action of the pulsed laser is received. The continuous laser beam is divided into the first interference local oscillator beam and the second interference local oscillator beam; When the detection height is less than the switching threshold, the backscattered signal is switched to the classical interferometric detection channel and coupled with the first interferometric local oscillator to obtain a classical interferometric signal, and the classical interferometric signal is detected to obtain classical interferometric detection data; The first wind speed information data in the target airspace below the switching threshold is calculated based on the classical interferometric detection data. The power intensity of the second interferometric local oscillator light is adjusted to obtain a quantum interference local oscillator light whose intensity is in a set ratio to the intensity of the backscattered signal. When the detection height is greater than the switching threshold, the backscattering signal is switched to the quantum interference detection channel to perform quantum interference with the quantum interference local oscillator to obtain a first single-photon signal and a second single-photon signal. The first single-photon signal and the second single-photon signal are then detected to obtain first single-photon detection data and second single-photon detection data. The second wind speed information data in the target airspace above the switching threshold is calculated based on the first single-photon detection data and the second single-photon detection data.

9. The wind measurement method based on quantum interference according to claim 8, characterized in that, The switching threshold is 15km. When the detection altitude is higher than 15km, the backscattered signal is switched to the quantum interference detection channel through an optical switch. When the detection altitude is lower than 15km, the backscattered signal is switched to the classical interference detection channel through an optical switch.

10. The wind measurement method based on quantum interference according to claim 9, characterized in that, The first wind speed information data is obtained by calculating based on classical interferometric detection data. The second wind speed information data is obtained by calculating based on the first single-photon detection data and the second single-photon detection data. The first wind speed information data and the second wind speed information data are spliced ​​together and cubic spline interpolation is performed to supplement the missing wind speed information data caused by the inherent response time of the optical switch when the optical switch switches to the backscattered signal. Finally, the wind speed information of the target airspace is obtained.

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