WO2023133666A1 - 激光雷达系统及光纤传感系统的自发辐射噪声的拟合方法 - Google Patents

激光雷达系统及光纤传感系统的自发辐射噪声的拟合方法 Download PDF

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WO2023133666A1
WO2023133666A1 PCT/CN2022/071204 CN2022071204W WO2023133666A1 WO 2023133666 A1 WO2023133666 A1 WO 2023133666A1 CN 2022071204 W CN2022071204 W CN 2022071204W WO 2023133666 A1 WO2023133666 A1 WO 2023133666A1
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output end
data
circulator
laser
telescope
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PCT/CN2022/071204
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English (en)
French (fr)
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王冲
杨可欣
杨斌
强蔚
薛向辉
赵若灿
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中国科学技术大学
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Priority to PCT/CN2022/071204 priority Critical patent/WO2023133666A1/zh
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
    • G01S17/02—Systems using the reflection of electromagnetic waves other than radio waves

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  • the invention relates to the technical field of laser radar, in particular to a fitting method of spontaneous radiation noise of a laser radar system and an optical fiber sensing system.
  • Lidar is an active modern optical remote sensing technology, and it is also a hot research field of atmospheric remote sensing. Following microwave radar, lidar increases the frequency of radiation sources to optical frequencies, four orders of magnitude higher than millimeter waves, which enables it to detect tiny targets, including aerosols and molecules in the atmosphere.
  • the laser radar emits laser pulses to the detection target, and after interacting with the target, the backscattering signal of the target is collected by the optical telescope, and input to the optical receiver, and the target information is obtained through photoelectric detection and data processing.
  • lidar can carry information with amplitude, frequency, phase, and polarization state. Therefore, lidar can not only accurately measure distance, but also accurately measure frequency shift, angle, attitude, and depolarization.
  • Lidar mainly includes: ranging lidar, speed measuring lidar, environmental monitoring lidar, imaging lidar, flash lidar, terrain mapping lidar, synthetic aperture lidar, etc.
  • the laser radar system can be divided into a laser output module and a receiver module.
  • the linearly polarized light generated by the continuous wave laser is modulated into pulsed light by the acousto-optic modulator, and then the power is amplified by the fiber amplifier, and then emitted by the telescope.
  • the fiber amplifier when the activated particles return to the ground state from the excited state and amplify the signal, random incoherent spontaneous emission of the excited particles will be generated. This spontaneous emission can be in any direction, and can cause further stimulated emission, and can be Amplified, this is called the spontaneous emission noise of the amplifier.
  • the spontaneous emission process will extract the energy stored in the gain fiber and consume a large number of upper energy level inversion particles, resulting in a decrease in the extraction rate of the signal to the gain. Therefore, the greater the spontaneous emission noise, the smaller the signal is amplified, that is, the smaller the signal gain. At the same time, the frequency band of spontaneous radiation noise is very wide, which can occupy the entire gain bandwidth and deteriorate the performance of the system.
  • the laser radar can be divided into two structures: a separate transceiver and a co-located transceiver.
  • the transceiver split structure adopts two optical systems of transmitting and receiving telescopes, the optical axes are not on the same axis, and the receiving telescope only receives atmospheric echo signals and background noise; while for the co-located system of transmitting and receiving, the transmitting system and receiving system use the same telescopic system , the optical axes coincide, so the receiving system will also be affected by the specular scattering of the transmitting system and the spontaneous emission noise of the laser.
  • this application provides a method for fitting the spontaneous emission noise of the laser radar system and the optical fiber sensing system, which can accurately measure the spontaneous emission noise, and improve the detection distance and detection data of the laser radar system and the optical fiber sensing system accuracy.
  • the present invention provides the following technical solutions:
  • a laser radar system comprising:
  • a signal source a co-located transceiver module and a separate transceiver module; the signal source is used to provide a trigger acquisition signal to simultaneously trigger the co-located transceiver module and the separate transceiver module to detect the detection target;
  • the co-located transceiver module has a first telescope, and the first telescope is used to emit a detection beam, and receive the co-located data returned by the detection target;
  • the separate transceiver module has a second telescope, and the first telescope The second telescope is used to receive the split data returned by the detection target; based on the co-located data and the split data, the noise of spontaneous emission is fitted.
  • the first telescope and the second telescope are different;
  • the first telescope is a monocular telescope, which is used to emit the detection light and receive the co-location data returned by the detection target at the same time;
  • the second telescope is a monocular telescope, which is used to receive the detection light returned by the detection target.
  • the split data for .
  • the above-mentioned laser radar system it also includes:
  • a host computer the host computer is used to perform data processing on the co-location data and the split-location data, so as to fit the spontaneous emission noise of the lidar system.
  • the co-location transceiver module further includes: a laser, an erbium-doped amplifier, a circulator, an optical switch, a filter, and a first detector, and the laser is used to emit the detection beam ;
  • the first output end of the signal source is connected to the input end of the laser
  • the output end of the laser is connected to the input end of the erbium-doped amplifier
  • the output end of the erbium-doped amplifier is connected to the input of the circulator end
  • the first output end of the circulator is connected to the first telescope
  • the second output end of the circulator is connected to the input end of the optical switch
  • the output end of the optical switch is connected to the input of the filter end
  • the output end of the filter is connected to the first input end of the first detector
  • the second output end of the signal source is connected to the second input end of the first detector
  • the first detector The output terminal is connected to the host computer.
  • the transceiver module further includes: a laser, an erbium-doped amplifier, a circulator, the first telescope and a second detector;
  • the first output end of the signal source is connected to the input end of the laser
  • the output end of the laser is connected to the input end of the erbium-doped amplifier
  • the output end of the erbium-doped amplifier is connected to the input of the circulator end
  • the first output end of the circulator is connected to the first telescope
  • the third output end of the signal source is connected to the first input end of the second detector
  • the output end of the second telescope is connected to the The second input end of the second detector, the output end of the second detector is connected to the host computer.
  • the present invention also provides a kind of optical fiber sensing system, described optical fiber sensing system comprises:
  • a signal source a laser, a circulator, an optical fiber disk, and an optical switch; the signal source is used to provide a trigger acquisition signal to trigger the laser to emit a detection beam to detect a detection target;
  • the optical switch is used to control the switch of the circulator, and the optical switch has a first state and a second state; in the first state, the optical switch is turned on, and the detection beam passes through the After the first output end of the circulator exits, it is output by the optical fiber disk, and the detection target returns colocated data based on the detection beam; in the second state, the optical switch cuts off the first output end of the circulator. An output end, the detection beam enters the optical switch through the second output end of the circulator, and receives split data.
  • the above optical fiber sensing system it also includes:
  • the first output end of the signal source is connected to the input end of the laser
  • the output end of the laser is connected to the input end of the erbium-doped amplifier
  • the output end of the erbium-doped amplifier is connected to the input of the circulator end
  • the first output end of the circulator is connected to the input end of the optical fiber disk
  • the second output end of the circulator is connected to the input end of the optical switch
  • the output end of the optical switch is connected to the filter
  • the input end of the filter, the output end of the filter is connected to the first input end of the detector
  • the second output end of the signal source is connected to the second input end of the detector
  • the output end of the detector is connected to The upper computer.
  • the present invention also provides a fitting method for spontaneous emission noise, the fitting method is applied to a laser radar system or an optical fiber sensing system, the laser radar system is the above laser radar system, and the optical fiber sensing system is the above-mentioned
  • the fitting method comprises:
  • the trigger acquisition signal is provided by the signal source
  • triggering the co-located transceiver module and the separate transceiver module Based on the triggering acquisition signal, triggering the co-located transceiver module and the separate transceiver module to perform synchronous detection to the detection target;
  • the spontaneous emission noise is fitted by a function.
  • the control variable method is used to obtain the spontaneous emission noise by comparing the co-located data and the separated data. , which is beneficial to evaluate the performance of the laser.
  • the spontaneous emission noise is measured, by selecting a filter with an appropriate bandwidth and a subsequent signal noise processing algorithm, the influence of the spontaneous emission noise on the echo signal can be removed, and the detection distance of the laser radar system and the optical fiber sensing system can be improved. and the accuracy of the detection data.
  • the calibrated monocular telescope can be used alone to realize the detection of single-photon radar without the interference of spontaneous emission noise.
  • FIG. 1 is a schematic structural diagram of a laser radar system provided by an embodiment of the present invention
  • FIG. 2 is a flow chart of a method for fitting spontaneous emission noise of a lidar system according to an embodiment of the present invention
  • Figure 3 is a comparison of the number of photons received by the separate transceiver module and the co-located transceiver module when the spontaneous emission noise is not corrected;
  • Figure 4 is a comparison diagram of the number of photons received by the separate transceiver module and the co-located transceiver module when the spontaneous emission noise has been corrected;
  • Fig. 5 is the cross-correlation coefficient between the ASE of the co-located terminal and the separated terminal after correction
  • Fig. 6 is a schematic structural diagram of an optical fiber sensing system provided by an embodiment of the present invention.
  • FIG. 1 is a schematic structural diagram of a lidar system provided by an embodiment of the present invention.
  • the working wavelength of the lidar system is 1548nm.
  • the lidar system includes:
  • Signal source 11 transceiver co-location module 100 and transceiver separation module 200; the signal source 11 is used to provide a trigger acquisition signal to simultaneously trigger the transceiver co-location module 100 and the transceiver separation module 200 to detect the target detection;
  • the transceiver co-location module 100 has a first telescope 15, and the first telescope 15 is used to emit a detection beam and receive the co-location data returned by the detection target; the transceiver module 200 has a second telescope 19.
  • the second telescope 19 is used to receive the split data returned by the detection target; based on the collocated data and the split data, fit the spontaneous emission noise.
  • the first telescope 15 is different from the second telescope 19;
  • the first telescope 15 is a monocular telescope, which is used to emit the detection light and receive the co-location data returned by the detection target at the same time;
  • the second telescope 19 is a monocular telescope, which is used to receive the detection light. The collocated data returned by the target.
  • the second telescope 19 is only used during factory calibration. After fitting the spontaneous emission noise (ASE noise), the single-photon radar detection without ASE noise interference can be realized by using the calibrated monocular alone.
  • ASE noise spontaneous emission noise
  • a host computer 21 which is used to perform data processing on the co-location data and the split data, so as to fit the spontaneous detection of the laser radar system. radiated noise.
  • both the co-location module 100 for transceiver and the separate module 200 for transceiver have a laser 12, an erbium-doped amplifier 13, a circulator 14, an optical switch 16, a filter 17, a first detector 18 and all The first telescope 15, the laser 12 is used to emit the detection beam;
  • the first output end of the signal source 11 is connected to the input end of the laser 12, the output end of the laser 12 is connected to the input end of the erbium-doped amplifier 13, and the output end of the erbium-doped amplifier 13 is connected to the The input end 1 of the circulator 14, the first output end 2 of the circulator 14 is connected to the first telescope 15, and the second output end 3 of the circulator 14 is connected to the input end of the optical switch 16, so The output end of the optical switch 16 is connected to the input end of the filter 17, the output end of the filter 17 is connected to the first input end of the first detector 18, and the second output end of the signal source 11 is connected to The second input end of the first detector 18 and the output end of the first detector 18 are connected to the host computer 21 .
  • the laser 12 when the signal source 11 provides a trigger acquisition signal, the laser 12 is triggered to emit the detection beam. After the detection beam is amplified by the erbium-doped amplifier 13, it passes through the first output of the circulator 14. The end 2 and the first telescope 15 emit, and the detection target returns co-location data based on the detection beam, and the first telescope 15 receives the co-location data and sends it to the circulator 14, and the circulator 14 passes through the circulator The second output terminal 3 of the device 14 enters the optical switch 16 to eliminate specular reflection, and then enters the first detector 18 after passing through the filter 17, and is transmitted to the upper position through the first detector 18 Machine 21.
  • the first detector 18 may be a single photon detector.
  • the transceiver module 200 also includes: a laser 12, an erbium-doped amplifier 13, a circulator 14, the first telescope 15 and a second detector 20; the second detector 20 can be Single Photon Detector.
  • the first output end of the signal source 11 is connected to the input end of the laser 12, the output end of the laser 12 is connected to the input end of the erbium-doped amplifier 13, and the output end of the erbium-doped amplifier 13 is connected to the The input end 1 of the circulator 14, the first output end 2 of the circulator 14 is connected to the first telescope 15, and the third output end of the signal source 11 is connected to the first input of the second detector 20 end, the output end of the second telescope 19 is connected to the second input end of the second detector 20 , and the output end of the second detector 20 is connected to the host computer 21 .
  • the laser 12 when the signal source 11 provides a trigger acquisition signal, the laser 12 is triggered to emit the detection beam. After the detection beam is amplified by the erbium-doped amplifier 13, it passes through the first output of the circulator 14. end 2 and the first telescope 15, the detection target returns split data based on the detection beam, the second telescope 19 receives the split data and sends it to the second detector 20, and the The second detector 20 is transmitted to the host computer 21, and the host computer 21 performs data processing based on the collocation data and the separation data, and fits the spontaneous emission noise of the lidar system.
  • the controlled variable method is used to obtain spontaneous emission noise by fitting the co-located data and separated data, which is beneficial to evaluate the performance of the laser.
  • the spontaneous emission noise is measured, by selecting a filter with an appropriate bandwidth and a subsequent signal noise processing algorithm, the influence of the spontaneous emission noise on the echo signal can be removed, and the detection distance of the laser radar system and the optical fiber sensing system can be improved. and the accuracy of the detection data.
  • the calibrated monocular telescope can be used alone to realize the detection of single-photon radar without the interference of spontaneous emission noise.
  • another embodiment of the present invention also provides a method for fitting the spontaneous emission noise of the lidar system, as shown in FIG.
  • Flow chart of the fitting method of radiation noise, the fitting method includes:
  • Step S101 a trigger acquisition signal is provided by a signal source
  • Step S102 Based on the trigger acquisition signal, trigger the co-located transceiver module and the separate transceiver module to perform synchronous detection to the detection target;
  • Step S103 receiving the co-located data and separated data returned by the detection target
  • Step S104 Subtracting local noise from the co-located data and the separated data respectively;
  • Step S105 selecting a linear interval to normalize the collocation data
  • Step S106 taking a difference between the normalized co-located data and the separated data to obtain spontaneous emission noise
  • Step S107 Fitting the spontaneous emission noise through a function.
  • the signal source provides a trigger acquisition signal to trigger the co-located transceiver module and the separate transceiver module to perform synchronous detection to the detection target. Then the local noise is subtracted from the received co-location data and split-location data to exclude the influence of background noise.
  • N(R) represents the number of echo signal photons returned at the distance R
  • E represents the photon number of the outgoing pulse
  • ⁇ 0 represents the optical receiving efficiency of the whole system
  • ⁇ q is the quantum efficiency of the detector
  • h Planck's constant
  • v is the frequency of the laser
  • A is the effective area of the second telescope
  • O(R) is the set overlap factor of the light spot receiving field of view
  • c is the speed of light
  • ⁇ t is the pulse width
  • ⁇ and ⁇ are the backscattering coefficients of the atmosphere and extinction coefficient.
  • S 0 and ⁇ 0 are the distance correction signal of the reference point position and the total idol scattering coefficient in the atmosphere, respectively. Differentiating the above formula with respect to distance can get:
  • ⁇ hom represents the atmospheric extinction coefficient calculated at this time assuming a homogeneous atmosphere. Therefore, intercept the interval where the slope of the echo signal received by the co-located transceiver module and the separate transceiver module is the same, so as to ensure that the co-located data and separated data to be processed subsequently are obtained by detecting the same section of uniform atmosphere.
  • the data of the co-located transceiver module is normalized:
  • N D (R) and N s (R) are the number of photons received by the co-located transceiver module and the separate transceiver module, respectively, n is the local noise, and C is a constant.
  • N sn (R) (N s (R)-n) ⁇ 10 c
  • the spontaneous emission noise N ASE (R) of the laser can be obtained by subtracting the normalized colocated data from the colocated data:
  • N ASE (R) N sn (R)-(N D (R)-n)
  • Figure 3 is a comparison of the number of photons received by the separate transceiver module and the co-located transceiver module when the spontaneous emission noise is not corrected
  • Figure 4 is the separate transceiver module and the co-located transceiver module when the spontaneous emission noise has been corrected
  • the comparison chart of the number of photons received by the module, Figure 5 is the correlation coefficient between the ASE of the co-located terminal and the separate terminal after correction.
  • 50 represents the photon number curve received by the transceiver split module
  • 60 represents the photon number curve received by the transceiver co-located module.
  • the control variable method is used to obtain the spontaneous emission noise by comparing the co-located data and the separated data, which is beneficial to the evaluation of the laser performance.
  • the spontaneous emission noise is measured, by selecting a filter with an appropriate bandwidth and a subsequent signal noise processing algorithm, the influence of the spontaneous emission noise on the echo signal can be removed, and the detection distance of the laser radar system and the optical fiber sensing system can be improved. and the accuracy of the detection data.
  • the calibrated monocular telescope can be used alone to realize the detection of single-photon radar without the interference of spontaneous emission noise.
  • FIG. 6 is a schematic structural diagram of an optical fiber sensor provided by an embodiment of the present invention.
  • the optical fiber sensing system includes :
  • a signal source 31 a laser 32, a circulator 34, an optical fiber disk 35, and an optical switch 36; the signal source 31 is used to provide a trigger acquisition signal to trigger the laser 32 to emit a detection beam to detect a detection target;
  • the optical switch 36 is used to control the switch of the circulator 34, and the optical switch 36 has a first state and a second state; in the first state, the optical switch 36 is turned on, and the detection After the light beam exits through the first output end 2 of the circulator 34, it is output by the optical fiber disk 35, and the detection target returns colocated data based on the detection light beam; in the second state, the optical switch 36 cuts off the first output end of the circulator 34, and the detection beam enters the optical switch 36 through the second output end 3 of the circulator 34 to receive split data.
  • Described host computer 39 is used for carrying out data processing to described colocation data and described split location data, to fit out described optical fiber sensing system spontaneous emission noise;
  • the first output end of the signal source 31 is connected to the input end of the laser 32, the output end of the laser 32 is connected to the input end of the erbium-doped amplifier 33, and the output end of the erbium-doped amplifier 33 is connected to the The input end 1 of the circulator 34, the first output end 2 of the circulator 34 is connected to the input end of the optical fiber disk 35, and the second output end 3 of the circulator 34 is connected to the input end of the optical switch 36 , the output end of the optical switch 36 is connected to the input end of the filter 37, the output end of the filter 37 is connected to the first input end of the detector 38, and the second output end of the signal source 31 is connected to The second input end of the detector 38 and the output end of the detector 38 are connected to the host computer 39 .
  • the optical switch 36 when the optical switch 36 is in the first state, the optical switch 36 is turned on, and the detection beam emitted by the laser 32 is amplified by the erbium-doped amplifier 33, and then passes through the first output terminal 2 of the circulator 34.
  • the optical switch 36 After exiting, it is transmitted by the optical fiber disk 35, and the detection target returns co-located data based on the detection beam, and the optical fiber disk 35 receives the co-located data and sends it to the circulator 34, and passes through the circulator
  • the second output terminal 3 of 34 enters the optical switch 36 to eliminate specular reflection, then enters the detector 38 after passing through the filter 37, and transmits to the host computer 39 through the detector 38;
  • the optical switch 36 cuts off the first output end 2 of the circulator 34, and the detection beam emitted by the laser 32 is amplified by the erbium-doped amplifier 33, and then passes through the second output of the circulator 34.
  • Terminal 3 enters the optical switch 36 to obtain split data, and then enters the detector 38 after passing through the filter 37 , and transmits to the host computer 39 through the detector 38 .
  • the acquisition of the co-located data and the separated data is realized through the control of the optical switch 36 on the circulator 34 .
  • the optical switch 36 When collecting co-location data, the optical switch 36 is turned on at this time, and the detection beam is transmitted through the first output end 2 of the circulator 34, transmitted by the optical fiber disk 35, and then reflected into the second output end 3 of the circulator 34, and passed through the optical switch 36.
  • the optical switch 36 After entering the filter 37; when collecting the divided data, the optical switch 36 cuts off the input of the first output terminal 2 of the circulator 34 at this time, then what is received at the second output terminal 3 of the circulator 34 is the divided signal without spontaneous emission noise. set data.
  • the control variable method is used to compare the co-located data and the separated data to obtain the spontaneous emission noise by fitting, which is beneficial to evaluate the performance of the laser.
  • the spontaneous emission noise is measured, by selecting a filter with an appropriate bandwidth and a subsequent signal noise processing algorithm, the influence of the spontaneous emission noise on the echo signal can be removed, and the detection distance of the laser radar system and the optical fiber sensing system can be improved. and the accuracy of the detection data.
  • the calibrated monocular telescope can be used alone to realize the detection of single-photon radar without the interference of spontaneous emission noise.
  • another embodiment of the present invention also provides a fitting method of spontaneous emission noise of the optical fiber sensing system, as shown in FIG. 2 , the fitting method includes:
  • Step S101 a trigger acquisition signal is provided by a signal source
  • Step S102 Based on the trigger acquisition signal, trigger the co-located transceiver module and the separate transceiver module to perform synchronous detection to the detection target;
  • Step S103 receiving the co-located data and separated data returned by the detection target
  • Step S104 Subtracting local noise from the co-located data and the separated data respectively;
  • Step S105 selecting a linear interval to normalize the collocation data
  • Step S106 taking a difference between the normalized co-located data and the separated data to obtain spontaneous emission noise
  • Step S107 Fitting the spontaneous emission noise through a function.
  • fitting method of the spontaneous emission noise adopted by the optical fiber sensing system and the lidar system is the same, and reference may be made to the fitting method of the spontaneous emission noise of the lidar system in the above embodiment, which will not be repeated here.
  • the control variable method is used to obtain the spontaneous emission noise by comparing the co-located data and the separated data, which is beneficial to the evaluation Laser performance.
  • the spontaneous emission noise is measured, by selecting a filter with an appropriate bandwidth and a subsequent signal noise processing algorithm, the influence of the spontaneous emission noise on the echo signal can be removed, and the detection distance of the laser radar system and the optical fiber sensing system can be improved. and the accuracy of the detection data.
  • the calibrated monocular telescope can be used alone to realize the detection of single-photon radar without the interference of spontaneous emission noise.

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Abstract

本申请公开了一种激光雷达系统及光纤传感系统的自发辐射噪声的拟合方法，使用控制变量法，通过对比同置数据和分置数据，拟合得到自发辐射噪声，有利于评估激光器的性能。在测量得到所述自发辐射噪声后，通过选取适当带宽的滤波器和后续的信号噪声处理算法，可以去除自发辐射噪声对回波信号的影响，提高激光雷达系统和光纤传感系统的探测距离和探测数据的准确性；另外，在拟合得到自发辐射噪声后，可以单独使用校准后的单筒望远镜实现没有自发辐射噪声干扰的单光子雷达的探测。

Description

激光雷达系统及光纤传感系统的自发辐射噪声的拟合方法 技术领域
本发明涉及激光雷达技术领域，尤其是涉及一种激光雷达系统及光纤传感系统的自发辐射噪声的拟合方法。
背景技术
激光雷达是一种主动的现代光学遥感技术，也是大气遥感的热点研究领域。继微波雷达后，激光雷达将辐射源的频率提高到了光频率，比毫米波高出四个数量级，这使之能够探测到微小的目标，包括大气中的气溶胶和分子。激光雷达通过向探测目标发射激光脉冲，与目标相互作用后，目标后向散射信号通过光学望远镜收集，并输入光学接收机，经光电探测和数据处理，获得目标信息。以激光为载体，激光雷达可以用振幅、频率、相位、偏振态来搭载信息。因此，激光雷达不仅可以精确测距，还可以精确测量频移、角度、姿态、退偏振。激光雷达主要包括：测距激光雷达、测速激光雷达、环境监测激光雷达、成像激光雷达、闪光激光雷达、地形测绘激光雷达、合成孔径激光雷达等。
激光雷达系统可以分为激光出射模块和接收机模块。在激光出射模块，连续波激光器产生的线偏振光经声光调制器调制为脉冲光，再由光纤放大器进行功率放大，然后由望远镜出射。在光纤放大器中，激活粒子从激发态返回基态并放大信号的同时，会产生受激粒子的随机非相干自发辐射，这种自发辐射可在任何方向，并可引起进一步受激辐射，且可被放大，称此为放大器的自发辐射噪声。自发辐射过程会提取增益光纤中存储的能量，消耗大量的上能级反转粒子，导致信号对增益的提取率降低。因此，自发辐射噪声越大，信号被放大的功率越小，即信号增益越小。同时，自发辐射噪声的频带很宽，可占据整个增益带宽，使系统的性能恶化。
根据激光雷达光学发射系统和接收系统的光轴是否同轴，激光雷达可 以区分为收发分置和收发同置两种结构。收发分置结构采用发射和接收两个望远镜光学系统，光轴不同轴，接收望远镜仅接收大气回波信号和背景噪声；而对于收发同置系统，发射系统和接收系统采用同一个望远系统，光轴重合，因此接收系统还会受到发射系统的镜面散射和激光器自发辐射噪声的影响。
发明内容
有鉴于此，本申请提供了一种激光雷达系统及光纤传感系统的自发辐射噪声的拟合方法，可以精密的测量自发辐射噪声，提高激光雷达系统和光纤传感系统的探测距离和探测数据的准确性。
为了实现上述目的，本发明提供如下技术方案：
一种激光雷达系统，所述激光雷达系统包括：
信号源、收发同置模块和收发分置模块；所述信号源用于提供触发采集信号，以同时触发所述收发同置模块和所述收发分置模块向探测目标进行探测；
其中，所述收发同置模块具有第一望远镜，所述第一望远镜用于出射探测光束，并接收所述探测目标返回的同置数据；所述收发分置模块具有第二望远镜，所述第二望远镜用于接收所述探测目标返回的分置数据；基于所述同置数据和所述分置数据，拟合出自发辐射噪声。
优选的，在上述的激光雷达系统中，所述第一望远镜和所述第二望远镜不同；
所述第一望远镜为单筒望远镜，用于同时出射所述探测光和接收所述探测目标返回的所述同置数据；所述第二望远镜为单筒望远镜，用于接收所述探测目标返回的所述分置数据。
优选的，在上述的激光雷达系统中，还包括：
上位机，所述上位机用于对所述同置数据和所述分置数据进行数据处 理，以拟合出所述激光雷达系统的自发辐射噪声。
优选的，在上述的激光雷达系统中，所述收发同置模块还包括：激光器、掺铒放大器、环形器、光开关、滤波器以及第一探测器，所述激光器用于出射所述探测光束；
其中，所述信号源的第一输出端连接所述激光器的输入端，所述激光器的输出端连接所述掺铒放大器的输入端，所述掺铒放大器的输出端连接所述环形器的输入端，所述环形器的第一输出端连接所述第一望远镜，所述环形器的第二输出端连接所述光开关的输入端，所述光开关的输出端连接所述滤波器的输入端，所述滤波器的输出端连接所述第一探测器的第一输入端，所述信号源的第二输出端连接所述第一探测器的第二输入端，所述第一探测器的输出端连接上位机。
优选的，在上述的激光雷达系统中，所述收发分置模块还包括：激光器、掺铒放大器、环形器、所述第一望远镜以及第二探测器；
其中，所述信号源的第一输出端连接所述激光器的输入端，所述激光器的输出端连接所述掺铒放大器的输入端，所述掺铒放大器的输出端连接所述环形器的输入端，所述环形器的第一输出端连接所述第一望远镜，所述信号源的第三输出端连接所述第二探测器的第一输入端，所述第二望远镜的输出端连接所述第二探测器的第二输入端，所述第二探测器的输出端连接上位机。
本发明还提供一种光纤传感系统，所述光纤传感系统包括：
信号源、激光器、环形器、光纤盘以及光开关；所述信号源用于提供触发采集信号，以触发所述激光器出射探测光束向探测目标进行探测；
其中，所述光开关用于控制所述环形器的开关，所述光开关具有第一状态和第二状态；在所述第一状态时，所述光开关打开，所述探测光束经所述环形器的第一输出端出射后，由所述光纤盘输出，所述探测目标基于所述探测光束返回同置数据；在所述第二状态时，所述光开关切断所述环 形器的第一输出端，所述探测光束经所述环形器的第二输出端进入所述光开关，接收分置数据。
优选的，在上述的光纤传感系统中，还包括：
掺铒放大器、滤波器、探测器以及上位机；所述上位机用于对所述同置数据和所述分置数据进行数据处理，以拟合出所述光纤传感系统的自发辐射噪声；
其中，所述信号源的第一输出端连接所述激光器的输入端，所述激光器的输出端连接所述掺铒放大器的输入端，所述掺铒放大器的输出端连接所述环形器的输入端，所述环形器的第一输出端连接所述光纤盘的输入端，所述环形器的第二输出端连接所述光开关的输入端，所述光开关的输出端连接所述滤波器的输入端，所述滤波器的输出端连接所述探测器的第一输入端，所述信号源的第二输出端连接所述探测器的第二输入端，所述探测器的输出端连接所述上位机。
本发明还提供一种自发辐射噪声的拟合方法，所述拟合方法应用于激光雷达系统或光纤传感系统，所述激光雷达系统为上述的激光雷达系统，所述光纤传感系统为上述的光纤传感系统，所述拟合方法包括：
由信号源提供触发采集信号；
基于所述触发采集信号，触发收发同置模块和收发分置模块向探测目标进行同步探测；
接收所述探测目标返回的同置数据和分置数据；
将所述同置数据和所述分置数据分别减去本地噪声；
选取线性区间对所述同置数据进行归一化；
将归一化后的所述同置数据和所述分置数据做差，得到自发辐射噪声；
通过函数对所述自发辐射噪声进行拟合。
通过上述描述可知，本发明技术方案提供的激光雷达系统及光纤传感系统的自发辐射噪声的拟合方法中，使用控制变量法，通过对比同置数据 和分置数据，拟合得到自发辐射噪声，有利于评估激光器的性能。同时在测量得到所述自发辐射噪声后，通过选取适当带宽的滤波器和后续的信号噪声处理算法，可以去除自发辐射噪声对回波信号的影响，提高激光雷达系统和光纤传感系统的探测距离和探测数据的准确性。另外，在拟合得到自发辐射噪声后，可以单独使用校准后的单筒望远镜实现没有自发辐射噪声干扰的单光子雷达的探测。
附图说明
为了更清楚地说明本申请实施例或现有技术中的技术方案，下面将对实施例或现有技术描述中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本申请的实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据提供的附图获得其他的附图。
本说明书附图所绘示的结构、比例、大小等，均仅用以配合说明书所揭示的内容，以供熟悉此技术的人士了解与阅读，并非用以限定本申请可实施的限定条件，故不具技术上的实质意义，任何结构的修饰、比例关系的改变或大小的调整，在不影响本申请所能产生的功效及所能达成的目的下，均应仍落在本申请所揭示的技术内容得能涵盖的范围内。
图1为本发明实施例提供的一种激光雷达系统的结构示意图；
图2为本发明实施例提供的一种激光雷达系统的自发辐射噪声的拟合方法流程图；
图3为未修正自发辐射噪声时收发分置模块和收发同置模块接收到的光子数对比图；
图4为已修正自发辐射噪声时收发分置模块和收发同置模块接收到的光子数对比图；
图5为同置端ASE矫正后与分置端的互相关系数；
图6为本发明实施例提供的一种光纤传感系统的结构示意图。
具体实施方式
下面将结合本申请实施例中的附图，对本申请中的实施例进行清楚、完整地描述，显然，所描述的实施例仅仅是本申请一部分实施例，而不是全部的实施例。基于本申请中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于本申请保护的范围。
为使本申请的上述目的、特征和优点能够更加明显易懂，下面结合附图和具体实施方式对本申请作进一步详细的说明。
参考图1，图1为本发明实施例提供的一种激光雷达系统的结构示意图。其中，所述激光雷达系统的工作波长为1548nm。
如图1所示，所述激光雷达系统包括：
信号源11、收发同置模块100和收发分置模块200；所述信号源11用于提供触发采集信号，以同时触发所述收发同置模块100和所述收发分置模块200向探测目标进行探测；
其中，所述收发同置模块100具有第一望远镜15，所述第一望远镜15用于出射探测光束，并接收所述探测目标返回的同置数据；所述收发分置模块200具有第二望远镜19，所述第二望远镜19用于接收所述探测目标返回的分置数据；基于所述同置数据和所述分置数据，拟合出自发辐射噪声。
本发明实施例中，所述第一望远镜15和所述第二望远镜19不同；
所述第一望远镜15为单筒望远镜，用于同时出射所述探测光和接收所述探测目标返回的所述同置数据；所述第二望远镜19为单筒望远镜，用于接收所述探测目标返回的所述分置数据。
需要说明的是，第二望远镜19只在出厂校准时使用。在拟合得到自发辐射噪声(ASE噪声)后，就可以单独使用校准后的单筒望远镜实现没有ASE噪声干扰的单光子雷达的探测。
基于图1所示激光雷达系统，还包括：上位机21，所述上位机21用 于对所述同置数据和所述分置数据进行数据处理，以拟合出所述激光雷达系统的自发辐射噪声。
如图1所示，所述收发同置模块100和所述收发分置模块200均具有激光器12、掺铒放大器13、环形器14、光开关16、滤波器17以及第一探测器18以及所述第一望远镜15，所述激光器12用于出射所述探测光束；
其中，所述信号源11的第一输出端连接所述激光器12的输入端，所述激光器12的输出端连接所述掺铒放大器13的输入端，所述掺铒放大器13的输出端连接所述环形器14的输入端1，所述环形器14的第一输出端2连接所述第一望远镜15，所述环形器14的第二输出端3连接所述光开关16的输入端，所述光开关16的输出端连接所述滤波器17的输入端，所述滤波器17的输出端连接所述第一探测器18的第一输入端，所述信号源11的第二输出端连接所述第一探测器18的第二输入端，所述第一探测器18的输出端连接所述上位机21。
具体的，当所述信号源11提供触发采集信号时，触发所述激光器12出射所述探测光束，所述探测光束经过所述掺铒放大器13放大后，经所述环形器14的第一输出端2和所述第一望远镜15出射，所述探测目标基于所述探测光束返回同置数据，所述第一望远镜15接收所述同置数据并发送至所述环形器14，经所述环形器14的第二输出端3进入所述光开关16，以消除镜面反射，然后经过所述滤波器17后进入所述第一探测器18，经所述第一探测器18传输至所述上位机21。
其中，所述第一探测器18可以为单光子探测器。
如图1所示，所述收发分置模块200还包括：激光器12、掺铒放大器13、环形器14、所述第一望远镜15以及第二探测器20；所述第二探测器20可以为单光子探测器。
其中，所述信号源11的第一输出端连接所述激光器12的输入端，所述激光器12的输出端连接所述掺铒放大器13的输入端，所述掺铒放大器 13的输出端连接所述环形器14的输入端1，所述环形器14的第一输出端2连接所述第一望远镜15，所述信号源11的第三输出端连接所述第二探测器20的第一输入端，所述第二望远镜19的输出端连接所述第二探测器20的第二输入端，所述第二探测器20的输出端连接所述上位机21。
具体的，当所述信号源11提供触发采集信号时，触发所述激光器12出射所述探测光束，所述探测光束经过所述掺铒放大器13放大后，经所述环形器14的第一输出端2和所述第一望远镜15出射，所述探测目标基于所述探测光束返回分置数据，所述第二望远镜19接收所述分置数据并发送至所述第二探测器20，经所述第二探测器20传输至所述上位机21，所述上位机21基于所述同置数据和所述分置数据进行数据处理，拟合出所述激光雷达系统的自发辐射噪声。
通过上述描述可知，本发明技术方案提供的激光雷达系统中，使用控制变量法，通过对同置数据和分置数据，拟合得到自发辐射噪声，有利于评估激光器的性能。同时在测量得到所述自发辐射噪声后，通过选取适当带宽的滤波器和后续的信号噪声处理算法，可以去除自发辐射噪声对回波信号的影响，提高激光雷达系统和光纤传感系统的探测距离和探测数据的准确性。另外，在拟合得到自发辐射噪声后，可以单独使用校准后的单筒望远镜实现没有自发辐射噪声干扰的单光子雷达的探测。
基于上述激光雷达系统，本发明另一实施例还提供一种激光雷达系统的自发辐射噪声的拟合方法，如图2所示，图2为本发明实施例提供的一种激光雷达系统的自发辐射噪声的拟合方法流程图，所述拟合方法包括：
步骤S101：由信号源提供触发采集信号；
步骤S102：基于所述触发采集信号，触发收发同置模块和收发分置模块向探测目标进行同步探测；
步骤S103：接收所述探测目标返回的同置数据和分置数据；
步骤S104：将所述同置数据和所述分置数据分别减去本地噪声；
步骤S105：选取线性区间对所述同置数据进行归一化；
步骤S106：将归一化后的所述同置数据和所述分置数据做差，得到自发辐射噪声；
步骤S107：通过函数对所述自发辐射噪声进行拟合。
具体的，首先由信号源提供触发采集信号，以触发收发同置模块和收发分置模块向探测目标进行同步探测。然后将接收到的同置数据和分置数据分别减去本地噪声，排除背景噪声的影响。
忽略本地噪声的激光雷达系统的光子数形式为:
Figure PCTCN2022071204-appb-000001
其中N(R)代表距离R处返回的回波信号光子数，E代表出射脉冲的光子数，η 0代表整个系统的光学接收效率，η q是探测器的量子效率，h是普朗克常数，v是激光的频率，A是第二望远镜的有效面积，O(R)是光斑接收视场的集合重叠因子，c是光速，Δt是脉冲宽度，β和σ分别是大气的后向散射系数和消光系数。
在计算过程中，使用对数后的距离修正信号S(R)会大大提高运算速度：
S(R)＝In[R 2N(R)]
若选取一个参考点，其距离激光出射位置R 0，则上述可以写为：
Figure PCTCN2022071204-appb-000002
其中，S 0和β 0分别为参考点位置的距离修正信号和大气中总的偶像散射系数。再将上式对距离求微分可以得到：
Figure PCTCN2022071204-appb-000003
当激光雷达系统的大气较为均匀时，可以认为后向散射系数不随距离的改变而改变，那么上式右边第一项便约掉了，变为：
Figure PCTCN2022071204-appb-000004
σ hom的角标代表了此时计算出的大气消光系数假设了大气均匀。因此，截取收发同置模块和收发分置模块接收到的回波信号斜率相同的区间，以保证后续所处理的同置数据和分置数据是对同一段均匀大气进行探测得到的。
为了排除收发同置模块的光开关、滤波器以及收发同置模块和收发分置模块镜筒大小不一致产生的影响，对收发同置模块的数据进行归一化：
log 10((N D(R)-n)R 2)-log 10((N s(R)-n)R 2)＝C
其中N D(R)和N s(R)分别为收发同置模块和收发分置模块接收到的光子数，n为本地噪声，C为常数。
由上式可得到归一化后的同置数据N sn(R)为：
N sn(R)＝(N s(R)-n)×10 c
将归一化后的同置数据减去分置数据就可获得激光器的自发辐射噪声N ASE(R)：
N ASE(R)＝N sn(R)-(N D(R)-n)
最后，用如下形式的函数对自发辐射噪声进行拟合：
Figure PCTCN2022071204-appb-000005
参考图3-图5，图3为未修正自发辐射噪声时收发分置模块和收发同置模块接收到的光子数对比图，图4为已修正自发辐射噪声时收发分置模块和收发同置模块接收到的光子数对比图，图5为同置端ASE矫正后与分置端的互相关系数。
图3-图5所示方式中，50表示的是收发分置模块接收到的光子数曲线，60表示的是收发同置模块接收到的光子数曲线，可以看到，与修正前相比，修正后收发分置模块和收发同置模块的数据达到了很高的相关度，说明本发明对自发辐射噪声实现了有效的拟合。
通过上述描述可知，本发明技术方案提供的激光雷达系统的自发辐射噪声的拟合方法中，使用控制变量法，通过对比同置数据和分置数据，拟合得到自发辐射噪声，有利于评估激光器的性能。同时在测量得到所述自发辐射噪声后，通过选取适当带宽的滤波器和后续的信号噪声处理算法，可以去除自发辐射噪声对回波信号的影响，提高激光雷达系统和光纤传感系统的探测距离和探测数据的准确性。另外，在拟合得到自发辐射噪声后，可以单独使用校准后的单筒望远镜实现没有自发辐射噪声干扰的单光子雷达的探测。
基于上述实施例，本发明另一实施例还提供一种光纤传感系统，如图6所示，图6为本发明实施例提供的一种光纤传感器的结构示意图，所述光纤传感系统包括：
信号源31、激光器32、环形器34、光纤盘35以及光开关36；所述信号源31用于提供触发采集信号，以触发所述激光器32出射探测光束向探测目标进行探测；
其中，所述光开关36用于控制所述环形器34的开关，所述光开关36具有第一状态和第二状态；在所述第一状态时，所述光开关36打开，所述探测光束经所述环形器34的第一输出端2出射后，由所述光纤盘35输出， 所述探测目标基于所述探测光束返回同置数据；在所述第二状态时，所述光开关36切断所述环形器34的第一输出端，所述探测光束经所述环形器34的第二输出端3进入所述光开关36，接收分置数据。
基于图6所示光纤传感系统，还包括：
掺铒放大器33、滤波器37、探测器38以及上位机39；所述上位机39用于对所述同置数据和所述分置数据进行数据处理，以拟合出所述光纤传感系统的自发辐射噪声；
其中，所述信号源31的第一输出端连接所述激光器32的输入端，所述激光器32的输出端连接所述掺铒放大器33的输入端，所述掺铒放大器33的输出端连接所述环形器34的输入端1，所述环形器34的第一输出端2连接所述光纤盘35的输入端，所述环形器34的第二输出端3连接所述光开关36的输入端，所述光开关36的输出端连接所述滤波器37的输入端，所述滤波器37的输出端连接所述探测器38的第一输入端，所述信号源31的第二输出端连接所述探测器38的第二输入端，所述探测器38的输出端连接所述上位机39。
具体的，当光开关36在第一状态时，所述光开关36打开，所述激光器32发出的探测光束经过所述掺铒放大器33放大后，经所述环形器34的第一输出端2出射后，由所述光纤盘35传输，所述探测目标基于所述探测光束返回同置数据，所述光纤盘35接收所述同置数据并发送至所述环形器34，经所述环形器34的第二输出端3进入所述光开关36，以消除镜面反射，然后经过所述滤波器37后进入所述探测器38，经所述探测器38传输至所述上位机39；在第二状态时，所述光开光36切断所述环形器34的第一输出端2，所述激光器32发出的探测光束经过所述掺铒放大器33放大后，经所述环形器34的第二输出端3进入所述光开关36，获取分置数据，然后经过所述滤波器37后进入所述探测器38，经所述探测器38传输至所述上位机39。
在光纤传感系统中，对同置数据和分置数据的获取是通过光开关36对环形器34的控制实现的。采集同置数据时，此时光开关36打开，探测光束经环 形器34的第一输出端2出射后，由光纤盘35传输，然后反射进入环形器34的第二输出端3，经光开关36后进入滤波器37；采集分置数据时，此时光开关36切断环形器34的第一输出端2的输入，那么在环形器34的第二输出端3接收到的就是没有自发辐射噪声的分置数据。
通过上述描述可知，本发明技术方案提供的光纤传感系统中，使用控制变量法，通过对比同置数据和分置数据，拟合得到自发辐射噪声，有利于评估激光器的性能。同时在测量得到所述自发辐射噪声后，通过选取适当带宽的滤波器和后续的信号噪声处理算法，可以去除自发辐射噪声对回波信号的影响，提高激光雷达系统和光纤传感系统的探测距离和探测数据的准确性。另外，在拟合得到自发辐射噪声后，可以单独使用校准后的单筒望远镜实现没有自发辐射噪声干扰的单光子雷达的探测。
基于上述光纤传感系统，本发明另一实施例还提供一种光纤传感系统的自发辐射噪声的拟合方法，如图2所示，所述拟合方法包括：
步骤S101：由信号源提供触发采集信号；
步骤S102：基于所述触发采集信号，触发收发同置模块和收发分置模块向探测目标进行同步探测；
步骤S103：接收所述探测目标返回的同置数据和分置数据；
步骤S104：将所述同置数据和所述分置数据分别减去本地噪声；
步骤S105：选取线性区间对所述同置数据进行归一化；
步骤S106：将归一化后的所述同置数据和所述分置数据做差，得到自发辐射噪声；
步骤S107：通过函数对所述自发辐射噪声进行拟合。
需要说明的是，光纤传感系统和激光雷达系统采用的自发辐射噪声的拟合方法一样，可以参考上述实施例中激光雷达系统的自发辐射噪声的拟合方法，此处不再赘述。
通过上述描述可知，本发明技术方案提供的光纤传感系统的自发辐射噪声的拟合方法中，使用控制变量法，通过对比同置数据和分置数据，拟合得到自发辐射噪声，有利于评估激光器的性能。同时在测量得到所述自发辐射噪声后，通过选取适当带宽的滤波器和后续的信号噪声处理算法，可以去除自发辐射噪声对回波信号的影响，提高激光雷达系统和光纤传感系统的探测距离和探测数据的准确性。另外，在拟合得到自发辐射噪声后，可以单独使用校准后的单筒望远镜实现没有自发辐射噪声干扰的单光子雷达的探测。
本说明书中各个实施例采用递进、或并列、或递进和并列结合的方式描述，每个实施例重点说明的都是与其他实施例的不同之处，各个实施例之间相同相似部分互相参见即可。
需要说明的是，在本文中，诸如第一和第二等之类的关系术语仅仅用来将一个实体或者操作与另一个实体或操作区分开来，而不一定要求或者暗示这些实体或操作之间存在任何这种实际的关系或者顺序。而且，术语“包括”、“包含”或者其任何其他变体意在涵盖非排他性的包含，从而使得包括一系列要素的物品或者设备不仅包括那些要素，而且还包括没有明确列出的其他要素，或者是还包括为这种物品或者设备所固有的要素。在没有更多限制的情况下，由语句“包括一个……”限定的要素，并不排除在包括上述要素的物品或者设备中还存在另外的相同要素。
对所公开的实施例的上述说明，使本领域专业技术人员能够实现或使用本申请。对这些实施例的多种修改对本领域的专业技术人员来说将是显而易见的，本文中所定义的一般原理可以在不脱离本申请的精神或范围的情况下，在其它实施例中实现。因此，本申请将不会被限制于本文所示的这些实施例，而是要符合与本文所公开的原理和新颖特点相一致的最宽的范围。

Claims (8)

  1. 一种激光雷达系统，其特征在于，所述激光雷达系统包括：信号源、收发同置模块和收发分置模块；所述信号源用于提供触发采集信号，以同时触发所述收发同置模块和所述收发分置模块向探测目标进行探测；
    其中，所述收发同置模块具有第一望远镜，所述第一望远镜用于出射探测光束，并接收所述探测目标返回的同置数据；所述收发分置模块具有第二望远镜，所述第二望远镜用于接收所述探测目标返回的分置数据；基于所述同置数据和所述分置数据，拟合出自发辐射噪声。
  2. 根据权利要求1所述的激光雷达系统，其特征在于，所述第一望远镜和所述第二望远镜不同；
    所述第一望远镜为单筒望远镜，用于同时出射所述探测光束和接收所述探测目标返回的所述同置数据；所述第二望远镜为单筒望远镜，用于接收所述探测目标返回的所述分置数据。
  3. 根据权利要求1所述的激光雷达系统，其特征在于，还包括：
    上位机，所述上位机用于对所述同置数据和所述分置数据进行数据处理，以拟合出所述激光雷达系统的自发辐射噪声。
  4. 根据权利要求1所述的激光雷达系统，其特征在于，所述收发同置模块还包括：激光器、掺铒放大器、环形器、光开关、滤波器以及第一探测器，所述激光器用于出射所述探测光束；
    其中，所述信号源的第一输出端连接所述激光器的输入端，所述激光器的输出端连接所述掺铒放大器的输入端，所述掺铒放大器的输出端连接所述环形器的输入端，所述环形器的第一输出端连接所述第一望远镜，所述环形器的第二输出端连接所述光开关的输入端，所述光开关的输出端连接所述滤波器的输入端，所述滤波器的输出端连接所述第一探测器的第一输入端，所述信号源的第二输出端连接所述第一探测器的第二输入端，所述第一探测器的输出端连接上位机。
  5. 根据权利要求1所述的激光雷达系统，其特征在于，所述收发分置模块还包括：激光器、掺铒放大器、环形器、所述第一望远镜以及第二探测器；
    其中，所述信号源的第一输出端连接所述激光器的输入端，所述激光器的输出端连接所述掺铒放大器的输入端，所述掺铒放大器的输出端连接所述环形器的输入端，所述环形器的第一输出端连接所述第一望远镜，所述信号源的第三输出端连接所述第二探测器的第一输入端，所述第二望远镜的输出端连接所述第二探测器的第二输入端，所述第二探测器的输出端连接上位机。
  6. 一种光纤传感系统，其特征在于，所述光纤传感系统包括：
    信号源、激光器、环形器、光纤盘以及光开关；所述信号源用于提供触发采集信号，以触发所述激光器出射探测光束向探测目标进行探测；
    其中，所述光开关用于控制所述环形器的开关，所述光开关具有第一状态和第二状态；在所述第一状态时，所述光开关打开，所述探测光束经所述环形器的第一输出端出射后，由所述光纤盘输出，所述探测目标基于所述探测光束返回同置数据；在所述第二状态时，所述光开关切断所述环形器的第一输出端，所述探测光束经所述环形器的第二输出端进入所述光开关，接收分置数据。
  7. 根据权利要求6所述的光纤传感系统，其特征在于，还包括：
    掺铒放大器、滤波器、探测器以及上位机；所述上位机用于对所述同置数据和所述分置数据进行数据处理，以拟合出所述光纤传感系统的自发辐射噪声；
    其中，所述信号源的第一输出端连接所述激光器的输入端，所述激光器的输出端连接所述掺铒放大器的输入端，所述掺铒放大器的输出端连接所述环形器的输入端，所述环形器的第一输出端连接所述光纤盘的输入端，所述环形器的第二输出端连接所述光开关的输入端，所述光开关的输出端 连接所述滤波器的输入端，所述滤波器的输出端连接所述探测器的第一输入端，所述信号源的第二输出端连接所述探测器的第二输入端，所述探测器的输出端连接所述上位机。
  8. 一种自发辐射噪声的拟合方法，所述拟合方法应用于激光雷达系统或光纤传感系统，所述激光雷达系统为如权利要求1-5任一项所述的激光雷达系统，所述光纤传感系统为如权利要求6或7所述的光纤传感系统，其特征在于，所述拟合方法包括：
    由信号源提供触发采集信号；
    基于所述触发采集信号，触发收发同置模块和收发分置模块向探测目标进行同步探测；
    接收所述探测目标返回的同置数据和分置数据；
    将所述同置数据和所述分置数据分别减去本地噪声；
    选取线性区间对所述同置数据进行归一化；
    将归一化后的所述同置数据和所述分置数据做差，得到自发辐射噪声；
    通过函数对所述自发辐射噪声进行拟合。
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5742416A (en) * 1996-03-28 1998-04-21 Ciena Corp. Bidirectional WDM optical communication systems with bidirectional optical amplifiers
CN105372670A (zh) * 2015-09-22 2016-03-02 中国科学院上海技术物理研究所 基于光学正交解调的相干零差多普勒测速激光雷达系统
CN108663671A (zh) * 2018-05-15 2018-10-16 合肥菲涅尔光电科技有限公司 一种基于dwdm的激光雷达系统
CN208013431U (zh) * 2018-03-01 2018-10-26 深圳市镭神智能系统有限公司 一种激光雷达
CN111257851A (zh) * 2020-04-03 2020-06-09 厦门大学 一种基于宽谱光源的光谱测量方法和光谱扫描激光雷达

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5742416A (en) * 1996-03-28 1998-04-21 Ciena Corp. Bidirectional WDM optical communication systems with bidirectional optical amplifiers
CN105372670A (zh) * 2015-09-22 2016-03-02 中国科学院上海技术物理研究所 基于光学正交解调的相干零差多普勒测速激光雷达系统
CN208013431U (zh) * 2018-03-01 2018-10-26 深圳市镭神智能系统有限公司 一种激光雷达
CN108663671A (zh) * 2018-05-15 2018-10-16 合肥菲涅尔光电科技有限公司 一种基于dwdm的激光雷达系统
CN111257851A (zh) * 2020-04-03 2020-06-09 厦门大学 一种基于宽谱光源的光谱测量方法和光谱扫描激光雷达

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