On-chip wind measurement laser radar system

Abstract

The invention discloses an on-chip wind measurement laser radar system which comprises a laser, a light splitting module, a pulse module, a lens, an optical mixer, a balance detection unit and a signal processing module. The light splitting module, the pulse module, the optical mixer and the balance detection unit are integrated on a chip; the laser is used for generating continuous laser; the light splitting module is used for splitting the continuous laser into local oscillation light and signal light; the pulse module is used for modulating the signal light into pulse light; the lens is used for emitting the pulsed light into the atmosphere and receiving back scattered light reflected by the aerosol hit into the atmosphere; the optical mixer is used for combining the back scattering light and the local oscillation light so as to output two groups of optical signals; the balance detection unit is used for receiving the two groups of optical signals and outputting two paths of orthogonal electric signals according to the two groups of optical signals; and the signal processing module is used for receiving the orthogonal electric signal and analyzing the orthogonal electric signal to obtain wind direction and wind speed information. By using the structure, the system volume is reduced, and the cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of wind-measuring laser radars, and in particular to an on-chip wind-measuring laser radar system. Background Art

[0002] Wind Lidar is a device that emits laser into the atmosphere, receives reflected light from tiny aerosol molecules in the atmosphere and performs coherent detection, thereby calculating wind speed and direction information in the atmosphere. Wind Lidar has a wide range of applications in scientific research and industrial production, for example: to measure the size of wind fields, thereby assisting in determining wind turbine site selection and estimating wind turbine revenue; to measure wind field information and guide the control of wind turbine attitude; to collect atmospheric information and forecast weather, etc.

[0003] However, the hardware of wind-measuring lidars currently on the market includes expensive optical devices such as lasers, acousto-optic modulators, and erbium-doped fiber amplifiers, which makes the final lidar unit price relatively high. In addition, the wind-measuring lidar system contains many devices, and each device is large in size and has high heat dissipation requirements, so the size of wind-measuring lidars is generally large. Considering that wind turbines are often installed in sparsely populated and wind-rich terrain, the size of the wind-measuring lidar will bring inconvenience to the early calculation of wind fields under complex terrain, and also bring challenges to the installation of radars on wind turbines in the later stage. Summary of the invention

[0004] The present invention provides an on-chip wind measurement laser radar system, which integrates a spectrometer module, a pulse module, an optical mixer and a balanced detection unit on a photonic chip, has high integration and strong photonic chip compatibility, reduces the volume of the wind measurement laser radar system, and reduces the system production cost.

[0005] The present invention provides an on-chip wind measurement laser radar system, comprising a signal transmitting module, a signal receiving module and a signal processing module;

[0006] The signal transmitting module includes a laser, a light splitting module, a pulse module and a lens; the signal receiving module includes an optical mixer and a balanced detection unit;

[0007] The light splitting module, pulse module, optical mixer and balanced detection unit are integrated on the same photonic chip;

[0008] The laser is used to generate continuous laser light; the spectrometer module is used to separate the continuous laser light into local oscillator light and signal light, so that the local oscillator light is transmitted to the optical mixer and the signal light is transmitted to the pulse module; the pulse module is used to modulate the signal light into pulse light with preset pulse parameters and transmit it to the lens; the lens is used to emit the pulse light into the atmosphere, receive the backscattered light reflected by the aerosol hitting the atmosphere, and transmit the backscattered light to the optical mixer; the optical mixer is used to combine the backscattered light and the local oscillator light to output two groups of optical signals to the balanced detection unit, the balanced detection unit is used to receive the two groups of optical signals, and output two orthogonal electrical signals according to the two groups of optical signals; the signal processing module is used to receive the orthogonal electrical signals and analyze the orthogonal electrical signals to obtain wind direction and wind speed information.

[0009] Optionally, the signal transmission module further includes an erbium-doped optical fiber amplifier;

[0010] The erbium-doped fiber amplifier is arranged between the pulse module and the lens; the erbium-doped fiber amplifier is used to amplify the peak power of the pulse light.

[0011] Optionally, the signal transmission module further includes a first edge coupler;

[0012] The first edge coupler is arranged between the pulse module and the erbium-doped fiber amplifier and integrated on the photon chip; the first edge coupler is used for coupling the pulse light into the erbium-doped fiber amplifier.

[0013] Optionally, the system further comprises a circulator;

[0014] The circulator is arranged between the erbium-doped fiber amplifier and the lens; the circulator is used to transmit the amplified pulse light to the lens and transmit the backscattered light to the optical mixer.

[0015] Optionally, the signal receiving module further includes a second edge coupler;

[0016] The second edge coupler is arranged between the circulator and the optical mixer; the second edge coupler is used for coupling the backscattered light into the optical mixer.

[0017] Optionally, the pulse module includes a first phase shifter, a second phase shifter, a first coupler, and a second coupler;

[0018] The first phase shifter and the second phase shifter are connected in parallel and are arranged between the first coupler and the second coupler; the first coupler is located between the light splitting module and the first phase shifter, and the second coupler is arranged between the first phase shifter and the lens;

[0019] The first coupler is used to split the signal light into two fundamental mode lights of equal power, which enter the first phase shifter and the second phase shifter respectively; the first phase shifter and the second phase shifter are used to adjust the phase of the fundamental mode light; the second coupler is used to couple and output the two fundamental mode lights, so as to determine the preset pulse parameters of the pulse light according to the phase difference between the two fundamental mode lights.

[0020] Optionally, the balanced detection unit includes a first balanced detector and a second balanced detector;

[0021] The first balanced detector and the second balanced detector are both electrically connected to the signal processing module; and two electrical signals formed by the first balanced detector and the second balanced detector are orthogonal to each other.

[0022] Optionally, the optical mixer comprises a 90° optical mixer.

[0023] Optionally, the material of the photonic chip includes at least a silicon substrate.

[0024] Optionally, the lens includes a telephoto lens.

[0025] The technical solution of the present invention is to integrate a spectroscopic module, a pulse module, an optical mixer and a balanced detection unit on the same photonic chip, and transmit the continuous laser generated by a laser to the spectroscopic module, the spectroscopic module divides the continuous laser into local oscillator light and signal light, and transmits the local oscillator light to the optical mixer, and the signal light is transmitted to the pulse module; the pulse module modulates the signal light into pulse light with preset pulse parameters, and transmits it to the lens; the lens focuses the pulse light and emits it into the atmosphere, so that the pulse light hits the aerosol particles in the atmosphere, receives the backscattered light reflected by the aerosol particles hitting the atmosphere, and transmits the backscattered light to the optical mixer; the optical mixer mixes the backscattered light and the local oscillator light to form two groups of optical signals and outputs them to the balanced detection unit, the balanced detection unit receives the two groups of optical signals, and outputs two orthogonal electrical signals according to the two groups of optical signals; after receiving the orthogonal electrical signals, the signal processing module processes and analyzes the orthogonal electrical signals to finally obtain wind direction and wind speed information. By utilizing the above structure, by integrating the spectrometer module, pulse module, optical mixer and balanced detection unit on the same photonic chip, high integration and miniaturization are achieved without affecting the detection accuracy and efficiency of the system, which greatly reduces the volume of the wind measurement lidar system and reduces the production cost of the system, providing greater possibilities for mass production.

[0026] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0028] Figure 1 A structural diagram of an on-chip wind measurement laser radar system provided by an embodiment of the present invention;

[0029] Figure 2 A structural diagram of a second on-chip wind measurement laser radar system provided by an embodiment of the present invention;

[0030] Figure 3 A schematic diagram of the structure of a pulse module provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0031] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0032] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0033] In the first embodiment, Figure 1 The structure diagram of an on-chip wind laser radar system provided by an embodiment of the present invention is applicable to reducing the volume of the wind laser radar and reducing the production cost to accurately measure the wind speed and wind direction information within a range of 3 km, such as Figure 1As shown, the system includes a signal transmitting module 1, a signal receiving module 2 and a signal processing module 3; the signal transmitting module 1 includes a laser 11, a spectrometer module 12, a pulse module 13 and a lens 14; the signal receiving module 2 includes an optical mixer 21 and a balanced detection unit 22; the spectrometer module 12, the pulse module 13, the optical mixer 21 and the balanced detection unit 22 are integrated on the same photonic chip 4; the laser 11 is used to generate continuous laser light; the spectrometer module 12 is used to divide the continuous laser light into local oscillator light and signal light, so that the local oscillator light is transmitted to the optical mixer 21, and the signal light is transmitted to the pulse module 13; the pulse Module 13 is used to modulate the signal light into pulse light with preset pulse parameters and transmit it to lens 14; lens 14 is used to emit the pulse light into the atmosphere, receive the backscattered light reflected by the aerosol hitting the atmosphere, and transmit the backscattered light to the optical mixer 21; the optical mixer 21 is used to combine the backscattered light and the local oscillator light to output two groups of optical signals to the balanced detection unit 22, the balanced detection unit 22 is used to receive the two groups of optical signals, and output two orthogonal electrical signals according to the two groups of optical signals; the signal processing module 3 is used to receive the orthogonal electrical signals, and analyze the orthogonal electrical signals to obtain wind direction and wind speed information.

[0034] Among them, the laser 11 is a device that can emit a highly monochromatic, highly directional, and highly bright coherent laser beam. In this embodiment, the laser 11 is used to generate continuous laser. The spectrometer module 12 is used to split the laser emitted by the laser 11 to separate the oscillator light and the signal light for transmission respectively. In this embodiment, the spectrometer module 12 is an on-chip spectrometer module. Usually, the on-chip spectrometer module may include two or more different optical waveguides, and the coupling between the optical waveguides is used to achieve the laser splitting effect in a low-loss form. The pulse module 13 is a pulse modulator that can convert a stable signal into a pulse signal and can control the width, frequency, and intensity of the pulse. In this embodiment, the pulse module 13 is used to modulate the signal light into a pulse light with a definable pulse width, extinction ratio, and repetition frequency, so that the pulse light is incident on the lens 14. The lens 14 is used to focus and guide the pulse light to a specific target direction so that the pulse light can accurately reach the target object; after the pulse light beam is irradiated to the target object, part of the light will be reflected or scattered back, and the lens 14 is also used to receive these reflected or scattered light signals and guide them to the optical mixer 21 for detection. In this embodiment, the lens 14 can be an optical lens or a telephoto lens. The optical mixer 21 is a very important device in the field of optics and optoelectronics. It is mainly used to coherently mix two input light beams and obtain the phase change relationship between the two light beams by measuring the intensity of the four-way output light. The working principle of the optical mixer 21 is based on the principle of optical interference. Interference refers to the phenomenon that two light waves are superimposed in space to form an interference pattern. The optical mixer 21 uses the characteristics of interference to achieve frequency mixing; by coherently superimposing two input light signals, its beat frequency signal will be converted into a new frequency signal with the same frequency as the original beat frequency but a phase difference of 90°. In this embodiment, the optical mixer 21 includes but is not limited to a 90° optical mixer, which is mainly used to mix the incident backscattered light and the local oscillator light, and utilize the coherent superposition between the backscattered light and the local oscillator light to finally form two groups of optical signals. The balanced detection unit 22 is a photodetector based on differential technology, and its principle is similar to that of a balanced bridge, which can improve the sensitivity and anti-interference ability of the on-chip wind laser radar. In this embodiment, the balanced detection unit 22 is used to process the two groups of optical signals emitted by the optical mixer 21 to obtain two orthogonal electrical signals, and orthogonality means that the phase difference between the two electrical signals is 90°.

[0035] Specifically, the continuous laser light generated by the laser 11 will be input to the spectroscopic module 12, and the spectroscopic module 12 will split the input continuous laser light so that the laser light is divided into local oscillator light and signal light. The formed local oscillator light is transmitted to the optical mixer 21, and the signal light is transmitted to the pulse module 13. After receiving the signal light, the pulse module 13 will modulate the received signal light and finally output a pulse light with preset pulse parameters, wherein the preset pulse parameters may include but are not limited to pulse width, extinction ratio and repetition frequency. The pulse light output by the pulse module 13 will be input to the lens 14, and the lens 14 will focus the pulse light and output it into the space atmosphere. When the pulse light signal propagates in the atmosphere, it will hit the aerosol particles in the atmosphere. The aerosol particles will return a part of the hit pulse light to the lens 14 in the form of backscattered light. The lens 14 will receive the reflected backscattered light and transmit it to the optical mixer 21. After receiving the backscattered light, the optical mixer 21 mixes the received backscattered light and the local oscillator light to form four complex domain demodulated optical signals, and the angle differences of the four complex domain demodulated signals are 0°, -45°, 45° and 180°, respectively, wherein the optical signals with signal differences of 0° and 180° are one group, and the optical signals with signal differences of -45° and 45° are one group, thereby forming two groups of optical signals. The two groups of optical signals formed are respectively input to the balanced detection unit 22, which receives the two groups of optical signals and processes the two groups of optical signals to output two orthogonal electrical signals. The output two orthogonal electrical signals are transmitted to the signal processing module 3. After receiving the orthogonal electrical signals, the signal processing module 3 processes and analyzes the orthogonal electrical signals. Since the aerosol particles have speed, Doppler frequency shift will occur. When the signal processing module 3 processes and analyzes the orthogonal electrical signal, it can use the coherent detection technology to add the two orthogonal electrical signals in the complex domain to form an electrical signal, and perform fast Fourier transform on the formed electrical signal to obtain a spectrum signal including two frequency domain signals, one positive and one negative, wherein the absolute values ​​of the frequencies of the two positive and negative frequency domain signals are the same, representing the Doppler frequency shift of the aerosol particles, thereby determining the moving speed of the aerosol particles to obtain the wind speed information. Similarly, the positive and negative relationship between the peak values ​​corresponding to the frequencies in the positive and negative frequency domain signals indicates the direction of the wind to obtain the wind direction information.

[0036] It should be noted that, in this embodiment, the spectrometer module 12, the pulse module 13, the optical mixer 21 and the balanced detection unit 22 are integrated on the same photonic chip 4. The material of the photonic chip 4 may include but is not limited to a silicon substrate, that is, the spectrometer module 12, the pulse module 13, the optical mixer 21 and the balanced detection unit 22 may be etched on the silicon substrate. In this way, high integration and miniaturization are achieved without affecting the detection accuracy and detection efficiency of the system, which greatly reduces the volume of the wind measurement lidar system and reduces the production cost of the system, providing greater possibilities for mass production.

[0037] The technical solution of the embodiment of the present invention is to integrate a spectroscopic module, a pulse module, an optical mixer and a balanced detection unit on the same photonic chip, and transmit the continuous laser generated by the laser to the spectroscopic module, the spectroscopic module divides the continuous laser into local oscillator light and signal light, and transmits the local oscillator light to the optical mixer, and the signal light is transmitted to the pulse module; the pulse module modulates the signal light into a pulse light with preset pulse parameters, and transmits it to the lens; the lens focuses the pulse light and emits it into the atmosphere, so that the pulse light hits the aerosol particles in the atmosphere, receives the backscattered light reflected by the aerosol particles hitting the atmosphere, and transmits the backscattered light to the optical mixer; the optical mixer mixes the backscattered light and the local oscillator light to form two groups of optical signals and outputs them to the balanced detection unit, the balanced detection unit receives the two groups of optical signals, and outputs two orthogonal electrical signals according to the two groups of optical signals; after receiving the orthogonal electrical signals, the signal processing module processes and analyzes the orthogonal electrical signals to finally obtain wind direction and wind speed information. By utilizing the above structure, by integrating the spectrometer module, pulse module, optical mixer and balanced detection unit on the same photonic chip, high integration and miniaturization are achieved without affecting the detection accuracy and efficiency of the system, which greatly reduces the volume of the wind measurement lidar system and reduces the production cost of the system, providing greater possibilities for mass production.

[0038] Optional, Figure 2 The structure diagram of the second on-chip wind laser radar system provided by the embodiment of the present invention is shown in FIG. Figure 2 As shown, the signal transmission module 1 further includes an erbium-doped fiber amplifier 15 ; the erbium-doped fiber amplifier 15 is disposed between the pulse module 13 and the lens 14 ; the erbium-doped fiber amplifier 15 is used to amplify the peak power of the pulse light.

[0039] Among them, the erbium doped fiber amplifier 15 (Erbium Doped Fiber Amplifier, EDFA) is an optical amplifier that uses an optical fiber doped with erbium ions as a gain medium. The working principle of EDFA is based on the interaction between light and erbium ions. In this embodiment, the erbium doped fiber amplifier 15 is used to amplify the pulse light generated by the pulse module 13 to increase the peak power of the pulse light.

[0040] Optional, continue to refer to Figure 2 The signal transmission module 1 also includes a first edge coupler 16 ; the first edge coupler 16 is disposed between the pulse module 13 and the erbium-doped fiber amplifier 15 , and is integrated on the photonic chip 4 ; the first edge coupler 16 is used to couple the pulse light into the erbium-doped fiber amplifier 15 .

[0041] Among them, the first edge coupler 16 is a device for coupling an optical signal from an optical fiber to the photonic chip 4 or from the photonic chip 4 to an optical fiber. The first edge coupler 16 usually realizes the transmission of the optical signal by placing the optical fiber at the edge of the photonic chip 4 and aligning it precisely. In this embodiment, because the pulse light emitted by the photonic chip 4 is a waveguide mode light, it cannot be directly transmitted to the erbium-doped fiber amplifier 15 to realize the transmission of the pulse light in the optical fiber. Therefore, the first edge coupler 16 is arranged between the erbium-doped fiber amplifier 15 and the pulse module 13, so that the first edge coupler 16 couples the optical signal transmitted in the photonic chip 4 into the erbium-doped fiber amplifier 15 to ensure the normal transmission of the optical signal.

[0042] Optional, continue to refer to Figure 2 The system also includes a circulator 5; the circulator 5 is arranged between the erbium-doped fiber amplifier 15 and the lens 14; the circulator 5 is used to transmit the amplified pulse light to the lens 14, and transmit the backscattered light to the optical mixer 21.

[0043] The circulator 5 is a non-reciprocal multi-port device, which allows optical signals to be transmitted from one port to another in a specific direction, while preventing or significantly reducing reverse transmission, and preventing the transmitted signal from interfering with the received signal. In this embodiment, the circulator 5 is an optical fiber transmission, which includes three ports. The pulse light amplified by the erbium-doped fiber amplifier 15 transmits the pulse light to the lens 15 through the channel between the port 1 and the port 2 of the circulator 5. After the lens 15 receives the backscattered light, the backscattered light will be transmitted to the optical mixer 21 through the channel between the port 2 and the port 3 of the circulator 5, and will not interfere with the transmission of the transmission channel between the port 1 and the port 2.

[0044] Optional, continue to refer to Figure 2 The signal receiving module 2 further includes a second edge coupler 23 ; the second edge coupler 23 is disposed between the circulator 5 and the optical mixer 21 ; the second edge coupler 23 is used to couple the backscattered light into the optical mixer 21 .

[0045] The second edge coupler 23 has the same meaning as the first edge coupler 16. In this embodiment, the second edge coupler 23 is used to couple the backscattered light transmitted through the optical fiber in the circulator 5 into the optical mixer 21 of the photonic chip 4, so that the optical mixer 21 mixes the backscattered light with the local oscillator light.

[0046] Optional, continue to refer to Figure 2The balanced detection unit 22 includes a first balanced detector 221 and a second balanced detector 222; the first balanced detector 221 and the second balanced detector 222 are both electrically connected to the signal processing module 3; the two electrical signals formed by the first balanced detector 21 and the second balanced detector 22 are orthogonal to each other.

[0047] Among them, the first balanced detector 221 is used to convert a group of optical signals output by the optical mixer 21 into one electrical signal output; the second balanced detector 222 is used to convert another group of optical signals output by the optical mixer 21 into a second electrical signal output, and the phase difference between the electrical signal output by the first balanced detector 211 and the second electrical signal output by the second balanced detector 222 is 90°, that is, the two electrical signals are orthogonal.

[0048] Optional, Figure 3 A schematic diagram of a pulse module according to an embodiment of the present invention is provided. Figure 3 As shown, the pulse module 13 includes a first phase shifter 131, a second phase shifter 132, a first coupler 133 and a second coupler 134; the first phase shifter 131 and the second phase shifter 132 are connected in parallel and are arranged between the first coupler 133 and the second coupler 134; the first coupler 133 is located between the splitter module 12 and the first phase shifter 131, and the second coupler 134 is arranged between the first phase shifter 131 and the lens 14; the first coupler 133 is used to divide the signal light into two beams of fundamental mode light with equal power, so as to enter the first phase shifter 131 and the second phase shifter 132 respectively; the first phase shifter 131 and the second phase shifter 132 are used to adjust the phase of the fundamental mode light; the second coupler 134 is used to couple and output the two beams of fundamental mode light, so as to determine the preset pulse parameters of the pulse light according to the phase difference between the two beams of fundamental mode light.

[0049] Among them, the first phase shifter 131 and the second phase shifter 132 are devices capable of adjusting the phase of a signal. In the pulse module 13, the first phase shifter 131 and the second phase shifter 132 are used to change the phase of the input optical signal, thereby achieving precise control of the pulse shape. The first coupler 133 and the second coupler 134 are devices for transmitting signals or energy. In the pulse module 13, the first coupler 133 and the second coupler 134 are used to transmit an optical signal from one circuit or system to another circuit or system and ensure proper electrical isolation or matching.

[0050] Specifically, after the optical splitting module 12 separates the continuous laser into signal light and local oscillator light, the signal light is separated into two beams of fundamental mode light with equal power after passing through the first coupler 133, and enters the first phase shifter 131 and the second phase shifter 132 respectively. The first phase shifter 131 and the second phase shifter 132 can respectively adjust the phases of the two beams of fundamental mode light, and the two beams of fundamental mode light with phase adjustment enter the second coupler 134. The second coupler 134 couples the two beams of fundamental mode light, and the output coupled light enters the lens 14. When the first phase shifter 131 and the second phase shifter 132 adjust the phase difference of the two beams of fundamental mode light, the phase of the fundamental mode light of one phase shifter can be used as the reference phase, and only the phase of the fundamental mode light of the other phase shifter is adjusted. When the optical phase difference of the two fundamental mode lights is |Φ1-Φ2|=180°, where Φ1 can represent the phase of the fundamental mode light in the first phase shifter 131 or the fundamental mode light in the second phase shifter 132, and correspondingly, Φ2 can represent the phase of the fundamental mode light in the second phase shifter 132 or the fundamental mode light in the first phase shifter 131, at this time, the light output by the two fundamental mode lights after coupling occurs coherent destructive, and the output optical power reaches a minimum value. When the optical phase difference of the two fundamental mode lights is |Φ1-Φ2|=0°, at this time, the light output by the two fundamental mode lights after coupling occurs coherent constructive, and the output optical power reaches a maximum value. Therefore, the extinction ratio of the pulse light is determined according to the above two situations, the maximum and minimum values ​​of the output optical power, and the output optical power is adjusted so that the extinction ratio of the pulse light reaches the preset extinction ratio. In addition, by controlling the time required for the phase difference of the two fundamental mode lights to be 0°, the pulse width of the pulse light can be determined so that the pulse width of the pulse light reaches the preset pulse width. By controlling the modulation frequency of the first phase shifter 131 or the second phase shifter 132, the repetition frequency of the pulsed light can be determined so that the repetition frequency of the pulsed light reaches the preset repetition frequency, thereby achieving that the pulse module 13 outputs pulsed light with preset pulse parameters.

[0051] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0052] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An on-chip wind laser radar system, characterized in that: It includes a signal transmitting module, a signal receiving module and a signal processing module; The signal transmitting module includes a laser, a light splitting module, a pulse module and a lens; the signal receiving module includes an optical mixer and a balanced detection unit; The light splitting module, the pulse module, the optical mixer and the balanced detection unit are integrated on the same photonic chip; The laser is used to generate continuous laser light; the light splitting module is used to split the continuous laser light into local oscillator light and signal light, so that the local oscillator light is transmitted to the optical mixer, and the signal light is transmitted to the pulse module; The pulse module is used to modulate the signal light into a pulse light with preset pulse parameters and transmit it to the lens; The lens is used to emit the pulse light into the atmosphere, receive the backscattered light reflected by the aerosol hitting the atmosphere, and transmit the backscattered light to the optical mixer; The optical mixer is used to combine the backscattered light and the local oscillator light to output two groups of optical signals to the balanced detection unit. The balanced detection unit is used to receive the two groups of optical signals and output two orthogonal electrical signals according to the two groups of optical signals. The signal processing module is used to receive the orthogonal electrical signals and analyze the orthogonal electrical signals to obtain wind direction and wind speed information.

2. The on-chip wind laser radar system according to claim 1, characterized in that: The signal transmission module also includes an erbium-doped optical fiber amplifier; The erbium-doped fiber amplifier is arranged between the pulse module and the lens; the erbium-doped fiber amplifier is used to amplify the peak power of the pulse light.

3. The on-chip wind laser radar system according to claim 2, characterized in that: The signal transmission module also includes a first edge coupler; The first edge coupler is arranged between the pulse module and the erbium-doped fiber amplifier and integrated on the photonic chip; the first edge coupler is used to couple the pulse light into the erbium-doped fiber amplifier.

4. The on-chip wind laser radar system according to claim 2, characterized in that: Also included is a circulator; The circulator is arranged between the EDF amplifier and the lens; the circulator is used to transmit the amplified pulse light to the lens, and transmit the backscattered light to the optical mixer.

5. The on-chip wind laser radar system according to claim 4, characterized in that: The signal receiving module also includes a second edge coupler; The second edge coupler is arranged between the circulator and the optical mixer; the second edge coupler is used for coupling the backscattered light into the optical mixer.

6. The on-chip wind laser radar system according to claim 1, characterized in that: The pulse module includes a first phase shifter, a second phase shifter, a first coupler and a second coupler; The first phase shifter and the second phase shifter are connected in parallel and are arranged between the first coupler and the second coupler; the first coupler is located between the light splitting module and the first phase shifter, and the second coupler is arranged between the first phase shifter and the lens; The first coupler is used to split the signal light into two fundamental mode lights with equal power, so as to enter the first phase shifter and the second phase shifter respectively; the first phase shifter and the second phase shifter are used to adjust the phase of the fundamental mode light; The second coupler is used to couple and output the two beams of the fundamental mode light, so as to determine the preset pulse parameters of the pulse light according to the phase difference between the two beams of the fundamental mode light.

7. The on-chip wind laser radar system according to claim 1, characterized in that: The balanced detection unit includes a first balanced detector and a second balanced detector; The first balanced detector and the second balanced detector are both electrically connected to the signal processing module; and two electrical signals formed by the first balanced detector and the second balanced detector are orthogonal to each other.

8. The on-chip wind laser radar system according to claim 1, characterized in that: The optical mixer includes a 90° optical mixer.

9. The on-chip wind laser radar system according to claim 1, characterized in that: The material of the photonic chip includes at least a silicon substrate.

10. The on-chip wind laser radar system according to claim 1, characterized in that: The lens comprises a telephoto lens.

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