Detection method suitable for laser ranging and capable of resisting complex landform interference

Abstract

The invention relates to a complex landform interference resistant detection method suitable for laser ranging, and belongs to the technical field of photoelectric detection. According to the invention, an optical fiber phased array is added in a laser ranging detection framework to serve as a regulation and control mechanism, so that a laser field serving as a detection information carrier is controllable, and the shape of the emitted laser field can be changed according to needs; according to the invention, a laser field change mechanism is designed: a control system feeds back the condition to an optical fiber phased array through an emission control signal according to the condition that the echo of a detector becomes weak due to the shielding caused by a strong scattering medium in a detection path, so that the mode of an emission laser field is controlled by the optical fiber phased array to change; therefore, the effect of resisting the interference of the strong scattering medium is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of photoelectric detection, and in particular relates to a detection method suitable for laser ranging and resistant to interference from complex terrain. Background Art

[0002] Laser ranging has many advantages, such as easy control of detection parameters, direct acquisition of distance information, and high ranging accuracy. However, laser ranging is similar to other photoelectric detection methods, and is easily affected by strong scattering media such as clouds, smoke, and fog. If the target is blocked by clouds and smoke, the echo of the strong scattering medium and the echo of the target are of the same wavelength, which cannot be distinguished by the current detection method. Laser ranging has no effective means to distinguish the echo of clouds and smoke from the echo of the target. Therefore, the detection performance of laser ranging will be seriously affected by strong scattering media. There is an urgent need for a detection method for laser ranging that can penetrate strong scattering media. Summary of the invention

[0003] 1. Technical issues to be resolved

[0004] The technical problem to be solved by the present invention is to provide a laser distance measuring device and a detection method which have the ability to penetrate strong scattering media.

[0005] (II) Technical solution

[0006] In order to solve the above technical problems, the present invention provides a laser ranging device capable of penetrating strong scattering media, including a control system, a laser, a 1-to-n optical fiber beam splitter, an optical fiber phased array, a receiving optical system, a receiving detector and an information processing system;

[0007] The control system is used to give an emission control signal to drive the laser to emit laser light. The laser light is transmitted through the optical fiber and enters the optical fiber phased array through the 1-to-n optical fiber beam splitter. The change of the voltage signal given by the control system controls the change of the optical fiber equivalent cavity length, thereby realizing the control of the laser phase, so that the optical fiber phased array generates a laser light with a specific mode, that is, a specific cross-sectional shape. The laser light irradiates the target and enters the receiving optical system after reflection. When there is a strong scattering medium in the detection optical path, the control system adjusts the optical fiber phased array to automatically change the emitted laser mode, so that the mode of the laser field emitted by the optical fiber phased array changes until the non-diffraction characteristic of the laser light has a penetrating effect on the strong scattering medium.

[0008] The receiving optical system is used for transmitting the received laser to the receiving detector;

[0009] The receiving detector is used to transmit the laser response signal into the information processing system;

[0010] The information processing system is used to process the laser response signal to achieve distance measurement to the target.

[0011] The invention also provides a detection method for laser ranging that is implemented by using the device and is resistant to interference from complex terrain.

[0012] Preferably, the method comprises the following steps: a control system gives an emission control signal to drive the laser to emit laser light, the laser light is transmitted through the optical fiber, and enters the optical fiber phased array through a 1-to-n optical fiber beam splitter, and the change of the voltage signal given by the control system is used to control the change of the optical fiber equivalent cavity length, thereby realizing the control of the laser phase, so that the optical fiber phased array generates a laser light of a specific mode, i.e., a laser light of a specific cross-sectional shape, and the laser light irradiates the target, enters the receiving optical system after reflection, and then the laser light received by the receiving optical system enters the receiving detector, and the receiving detector transmits the laser response signal to the information processing system for processing, thereby realizing the distance measurement of the target; when there is a strong scattering medium in the detection optical path, the control system adjusts the optical fiber phased array to automatically change the emitted laser mode, so that the mode of the laser field emitted by the optical fiber phased array changes, until the non-diffraction characteristic of the laser light has a penetrating effect on the strong scattering medium, thereby playing the role of penetrating and resisting interference from the strong scattering medium.

[0013] (III) Beneficial effects

[0014] 1. The present invention adds a fiber phased array as a control mechanism in the laser ranging detection architecture, so that the laser field as the detection information carrier is controllable and the emitted laser field can be changed in shape as needed;

[0015] 2. The present invention designs a laser field change mechanism: according to the situation that the detector echo becomes weak due to the obstruction caused by the strong scattering medium in the detection path, the control system feeds back the situation to the fiber optic phased array through the emission control signal, so that the mode of controlling the emission of the laser field changes until the non-diffraction characteristic of the laser produces a penetrating effect on the strong scattering medium, thereby playing a role in resisting interference from the strong scattering medium. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of an implementation method of a laser ranging strong scattering medium penetration detection method controlled by an optical fiber phased array according to the present invention;

[0017] Figure 2 Schematic diagram of different laser field modes emitted after fiber phased array control. DETAILED DESCRIPTION

[0018] In order to make the purpose, content and advantages of the present invention more clear, the specific implementation methods of the present invention are further described in detail below in conjunction with the drawings and examples.

[0019] The present invention designs a detection method suitable for laser ranging and resisting interference from complex terrain. It is a detection method for laser ranging that penetrates strong scattering media such as clouds and smoke. It specifically relates to a laser ranging device and detection method that have the ability to penetrate strong scattering media. It has a strong anti-smoke interference function and is easy to be widely promoted in engineering applications.

[0020] The design of a laser ranging strong scattering medium penetration detection method controlled by an optical fiber phased array according to the present invention is described in detail below in conjunction with specific embodiments and drawings.

[0021] A schematic diagram of a laser distance measuring device having the ability to penetrate strong scattering media provided by the present invention is shown in FIG. Figure 1 As shown, it includes a control system, a laser, a 1-to-n fiber beam splitter, a fiber phased array, a receiving optical system, a receiving detector and an information processing system.

[0022] Among them, the control system gives an emission control signal to drive the laser to emit laser. The laser is transmitted through the optical fiber and enters the optical fiber phased array through the 1-to-n optical fiber beam splitter. The change of the voltage signal given by the control system controls the change of the optical fiber equivalent cavity length, thereby realizing the control of the laser phase, so that the optical fiber phased array generates a laser of a specific mode (i.e., a specific cross-sectional shape). The laser irradiates the target and enters the receiving optical system after reflection. The laser received by the receiving optical system then enters the receiving detector (such as an avalanche photodiode). The receiving detector transmits the laser response signal to the information processing system for processing to realize the distance measurement of the target. When there is a strong scattering medium in the detection optical path, the echo signal is weak and scattered. At this time, the control system adjusts the optical fiber phased array to automatically change the emitted laser mode. Figure 2 Several typical spot pattern distributions are given. The pattern of the laser field emitted by the fiber phased array changes until the non-diffraction characteristics of the laser produce a penetrating effect on the strong scattering medium, thereby playing a role in penetrating and resisting interference from the strong scattering medium.

[0023] The key design points of the present invention are as follows:

[0024] 1. Add a fiber phased array as a control mechanism in the laser ranging detection architecture to make the laser field as the detection information carrier controllable and enable the emitted laser field to change shape as needed;

[0025] 2. Design a laser field change mechanism: According to the situation where the detector echo becomes weak due to the obstruction caused by the strong scattering medium in the detection path, the control system feeds back the situation to the fiber optic phased array through the emission control signal, so that the mode of controlling the emission laser field changes until the non-diffraction characteristics of the laser have a penetrating effect on the strong scattering medium, thereby playing a role in resisting the interference of the strong scattering medium.

[0026] It can be seen that the method of the present invention is implemented by hardware anti-interference means and has high reliability; the implementation scheme has little improvement on traditional laser ranging and other detection devices and has a relatively mature engineering transformation potential.

[0027] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A laser distance measuring device capable of penetrating strong scattering media, characterized in that: It includes control system, laser, 1-to-n fiber beam splitter, fiber phased array, receiving optical system, receiving detector and information processing system; The control system is used to give an emission control signal to drive the laser to emit laser light. The laser light is transmitted through the optical fiber and enters the optical fiber phased array through the 1-to-n optical fiber beam splitter. The change of the voltage signal given by the control system controls the change of the optical fiber equivalent cavity length, thereby realizing the control of the laser phase, so that the optical fiber phased array generates a laser light with a specific mode, that is, a specific cross-sectional shape. The laser light irradiates the target and enters the receiving optical system after reflection. When there is a strong scattering medium in the detection optical path, the control system adjusts the optical fiber phased array to automatically change the emitted laser mode, so that the mode of the laser field emitted by the optical fiber phased array changes until the non-diffraction characteristic of the laser light has a penetrating effect on the strong scattering medium. The receiving optical system is used for transmitting the received laser to the receiving detector; The receiving detector is used to transmit the laser response signal into the information processing system; The information processing system is used to process the laser response signal to achieve distance measurement to the target.

2. The device according to claim 1, characterized in that The receiving detector is an avalanche photodiode.

3. The device according to claim 1, characterized in that The device is used in the field of photoelectric detection technology.

4. A detection method suitable for laser ranging and resistant to interference from complex terrain, implemented by using the device described in claim 1, 2 or 3.

5. The method according to claim 4, characterized in that The method comprises the following steps: a control system gives an emission control signal to drive a laser to emit laser, the laser is transmitted through an optical fiber, and enters an optical fiber phased array through a 1-to-n optical fiber beam splitter, and the change of the voltage signal given by the control system is used to control the change of the optical fiber equivalent cavity length, thereby realizing the control of the laser phase, so that the optical fiber phased array generates a laser with a specific mode, that is, a laser with a specific cross-sectional shape, the laser irradiates a target, enters a receiving optical system after reflection, and then the laser received by the receiving optical system enters a receiving detector, and the receiving detector transmits a laser response signal to an information processing system for processing, thereby realizing the distance measurement of the target; when a strong scattering medium exists in the detection optical path, the control system regulates the optical fiber phased array to automatically change the emitted laser mode, so that the mode of the laser field emitted by the optical fiber phased array changes, until the non-diffraction characteristic of the laser produces a penetration effect on the strong scattering medium, thereby playing the role of penetration and resistance to interference of the strong scattering medium.

6. The method according to claim 4, characterized in that The strong scattering medium is cloud or smoke.

7. The method according to claim 4, 5 or 6, characterized in that: The method is applied in the field of photoelectric detection technology.

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